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Discussion Starter #2
You want a varmint rifle, yet you've chosen 6.8mm SPC? :?:

With the ammo expense and current lack of ammo availability, why would you chose that caliber? I just finished a 6.8mm build and will be reloading, but finding brass alone is an issue right now.

Have you looked into the .204 Ruger? From what I've been reading it's got great ballistics further out than 6.8mm and .204 Ruger ammo appears to be readily available.

Not trying to get you to switch gears, just wanting to suggest that you look into 6.8mm thoroughly.
 
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Discussion Starter #3
If I was gonna build a "varmint AR", why not build it on the .243? The .204 is a pretty flat shooting round, but it's a bit light to be bucking gusts. The .223 isn't quite as flat shooting, but is plenty good for varmints, but the fact that you liked the 6.8 made me think you want something a little different. I think the .243 would be a good round for you, it's great on the varmints, flat shooting with the lightest rounds and still pretty flat shooting and not hard recoiling with some of the heavier bullets.
 
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Discussion Starter #4
Start with this. Go to www.gunbroker.com and type in 6.8 and see how many firearm/upper results you get then type in 6.5 grendel and see how many you get. 6.5 is more fluiddynamic, and has more punch. If you don't want a 22-250, 204 or 223 all great varmint rounds go for the 6.5 grendel, you can order the upper today, personally I'd say at minimum go a 20" barrel and free float barrel. www.65grendel.com has some charts that when you read them will make you realize, that 6.8 costs just as much and isn't nearly as good. Once you get the brass for 6.5, the 6.5 bullets are readily available.
 
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Discussion Starter #6
I still do NOT understand why so many people are all about the 6.5 Grendel and the .260. I have seen some claims about the 6.5 Grendel and the .260 saying that they’re both superior to the .308 in terms of wind drift, bc, kinetic energy, etc. I have even seen some articles like this http://demigodllc.com/articles/the-c...260-remington/ that are claming things like the .260 even puts the .300 winmag to shame. THIS IS HYPE AND COMPLETE BS. I will talk more about that issue in a sec.

I just wanted to start off this post by saying that I personally believe that there is WAY too much hype behind the 6.5 Grendel, .260 and the 6.8 spc. Now the 6.5 Grendel and the .260 are kind of a medium cartridge between the .308 and the .243. The 6.5 Grendel will fire some of the lighter bullets at a pretty decent speed. Chuck Hawk lists the 6.5 Gendel as firing a 100 grain bullet at around 2800 fps and 2850. http://www.chuckhawks.com/6-5mm_grendel.htm . Some of the heavier bullets like 120 grainers have a muzzle velocity between 2530-2630 fps. (also on chuck hawk’s page). The funny thing about people that claim the 6.5 Grendel is so much better than the .308 don’t take several things into account. The .308 will push a 150 grain bullet between 2980-2700 fps, depending on the load. http://www.pacinfo.com/~dropinsator/chart4.htm#308%20Win . Even the military has loading of the 168 grain bullet that are traveling at least 2680 fps. (a moderate loading, not too hot). This means that the .308 will push a bullet that is 48 grains heavier than the 6.5 Grendel, exactly the same speed. Since they will have a very similar time of flight, because they have a similar speed; this means that IF they were the same weight of bullet, they would have similar wind drift. They do NOT have the same weight of bullet, and therefore, the .308 will have LESS wind drift than the 6.5 Grendel. With some of the lighter bullets, the 6.5 Grendel MIGHT have the same or less wind drift. Because they have very similar velocities, the drop on the bullets will be slightly different, but still pretty close.

There are basically 2 thoughts on wind drift. You can fire a light bullet extremely fast; which means that it has a short time of flight, and therefore less time for the wind to affect the bullet. You can also fire a heavy bullet a little slower; although it will have a longer time of flight, since the projectile is heavier, it will be more difficult for the wind to push it.

The .243 sometimes DOES have less wind drift than the .308, even at long distances because of how much faster the bullets are sometimes moving. People that will claim the 6.5 Grendel, .260 or 6.8 spc have “better long range ballistics” than the .308, etc, are only talking about the very light bullets that the .260, 6.5 Grendel shoot, and comparing them to the heavier bullets that the .308 is shooting. Keep in mind that just because the bullet has less drop, does not mean that it will be a better long range cartridge, it merely means that the bullet will shoot flatter.

Something else that I always hear from the 6.5 Grendel and .260 guys: the high BC bullets of these calibers don’t slow down as quickly as the .30’s (.308, .300 winmag, etc), and they claim that even if they start out at close to the same speed, the BC means at longer range the .30’s aren’t going nearly as fast. For those guys that claim this, I have news for you, There ARE high BC bullets for the .30’s as well, some that have MUCH better BC’s than the 6.5 bullets. If I remember right, Lost River Ballistics (who got bought out by hooker I believe) had a 180 grain bullet that had a BC of something ridiculous like .89-90. I also think it’s funny how the guys that shoot 6.5mm Grendel or .260, like to compare the velocity of those rounds, against the .308 or .300 winmag out of a 24” barrel. You give a .300 winmag or a .308 a 26” barrel and some high BC bullets like 210 VLD’s, 180-190 Lost River, or 155 Scenars, and the 6.5 Grendel and .260 won’t even hold a candle to them. A .300 winmag will push a 180 grain bullet over 3,000 fps, and some of the 210 Bergers around 2700 fps. I assure you that the .260 can’t touch that kind of velocity and weight of bullet, but the guys that are all about the .260 say that it does.

Please realize that I am NOT saying that the 6.5 Grendel or the .260 are bad cartridges. I am merely saying that I believe that some of these cartridges are a fad, and that some of the guys that like to play with these cartridges are making people believe that they are the “cat’s meow”, and people aren’t looking at the ballistics. It’s fine if you want to have a caliber to play with that most everybody else doesn’t, just realize it probably doesn’t do anything special that other calibers can’t. The .260 and 6.5 Grendel both have their place, and I personally believe that’s right in between the .308 and .243. If you do not reload, I would personally stay away from the 6.5 Grendel, even if you do reload, I’d probably still consider the .243 or .243 AI. I would take the .243 AI any day of the week against the 6.5 Grendel, just from how easily you can get components and loads for each. From what I have heard there is only 1-2 makers of brass for the 6.5. There is also a pretty limited choice of bullet weights and manufacturers of them. With the .243 or .308 there are MANY choices of quality brass manufacturers and bullet manufacturers. If you just want to play with the 6.5 Grendel, then go for it, I just don’t want people expecting it to be the greatest thing in the world and beating the socks off of the .243 or .308, when it won’t. The 6.5 Grendel will cost you more to reload and shoot, you will have less choices of bullets, etc, and I personally believe won’t do anything special that others can’t do. Just look at the numbers for yourself, make an educated decision, and don’t buy into all the hype.
 
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Discussion Starter #9
Oh yeah, I just wanted to apologize if I hijacked the thread. That was not my intention, but I just felt like someone needed to cover the ballistics of the 6.5 a little better, since I know it's quite popular with the AR crowd.
 
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Discussion Starter #10
I still do NOT understand why so many people are all about the 6.5 Grendel and the .260. I have seen some claims about the 6.5 Grendel and the .260 saying that they’re both superior to the .308 in terms of wind drift, bc, kinetic energy, etc. I have even seen some articles like this http://demigodllc.com/articles/the-c...260-remington/ that are claming things like the .260 even puts the .300 winmag to shame. THIS IS HYPE AND COMPLETE BS. I will talk more about that issue in a sec.

I just wanted to start off this post by saying that I personally believe that there is WAY too much hype behind the 6.5 Grendel, .260 and the 6.8 spc. Now the 6.5 Grendel and the .260 are kind of a medium cartridge between the .308 and the .243. The 6.5 Grendel will fire some of the lighter bullets at a pretty decent speed. Chuck Hawk lists the 6.5 Gendel as firing a 100 grain bullet at around 2800 fps and 2850. http://www.chuckhawks.com/6-5mm_grendel.htm . Some of the heavier bullets like 120 grainers have a muzzle velocity between 2530-2630 fps. (also on chuck hawk’s page). The funny thing about people that claim the 6.5 Grendel is so much better than the .308 don’t take several things into account. The .308 will push a 150 grain bullet between 2980-2700 fps, depending on the load. http://www.pacinfo.com/~dropinsator/chart4.htm#308 Win . Even the military has loading of the 168 grain bullet that are traveling at least 2680 fps. (a moderate loading, not too hot). This means that the .308 will push a bullet that is 48 grains heavier than the 6.5 Grendel, exactly the same speed. Since they will have a very similar time of flight, because they have a similar speed; this means that IF they were the same weight of bullet, they would have similar wind drift. They do NOT have the same weight of bullet, and therefore, the .308 will have LESS wind drift than the 6.5 Grendel. With some of the lighter bullets, the 6.5 Grendel MIGHT have the same or less wind drift. Because they have very similar velocities, the drop on the bullets will be slightly different, but still pretty close.

There are basically 2 thoughts on wind drift. You can fire a light bullet extremely fast; which means that it has a short time of flight, and therefore less time for the wind to affect the bullet. You can also fire a heavy bullet a little slower; although it will have a longer time of flight, since the projectile is heavier, it will be more difficult for the wind to push it.

The .243 sometimes DOES have less wind drift than the .308, even at long distances because of how much faster the bullets are sometimes moving. People that will claim the 6.5 Grendel, .260 or 6.8 spc have “better long range ballistics” than the .308, etc, are only talking about the very light bullets that the .260, 6.5 Grendel shoot, and comparing them to the heavier bullets that the .308 is shooting. Keep in mind that just because the bullet has less drop, does not mean that it will be a better long range cartridge, it merely means that the bullet will shoot flatter.

Something else that I always hear from the 6.5 Grendel and .260 guys: the high BC bullets of these calibers don’t slow down as quickly as the .30’s (.308, .300 winmag, etc), and they claim that even if they start out at close to the same speed, the BC means at longer range the .30’s aren’t going nearly as fast. For those guys that claim this, I have news for you, There ARE high BC bullets for the .30’s as well, some that have MUCH better BC’s than the 6.5 bullets. If I remember right, Lost River Ballistics (who got bought out by hooker I believe) had a 180 grain bullet that had a BC of something ridiculous like .89-90. I also think it’s funny how the guys that shoot 6.5mm Grendel or .260, like to compare the velocity of those rounds, against the .308 or .300 winmag out of a 24” barrel. You give a .300 winmag or a .308 a 26” barrel and some high BC bullets like 210 VLD’s, 180-190 Lost River, or 155 Scenars, and the 6.5 Grendel and .260 won’t even hold a candle to them. A .300 winmag will push a 180 grain bullet over 3,000 fps, and some of the 210 Bergers around 2700 fps. I assure you that the .260 can’t touch that kind of velocity and weight of bullet, but the guys that are all about the .260 say that it does.

Please realize that I am NOT saying that the 6.5 Grendel or the .260 are bad cartridges. I am merely saying that I believe that some of these cartridges are a fad, and that some of the guys that like to play with these cartridges are making people believe that they are the “cat’s meow”, and people aren’t looking at the ballistics. It’s fine if you want to have a caliber to play with that most everybody else doesn’t, just realize it probably doesn’t do anything special that other calibers can’t. The .260 and 6.5 Grendel both have their place, and I personally believe that’s right in between the .308 and .243. If you do not reload, I would personally stay away from the 6.5 Grendel, even if you do reload, I’d probably still consider the .243 or .243 AI. I would take the .243 AI any day of the week against the 6.5 Grendel, just from how easily you can get components and loads for each. From what I have heard there is only 1-2 makers of brass for the 6.5. There is also a pretty limited choice of bullet weights and manufacturers of them. With the .243 or .308 there are MANY choices of quality brass manufacturers and bullet manufacturers. If you just want to play with the 6.5 Grendel, then go for it, I just don’t want people expecting it to be the greatest thing in the world and beating the socks off of the .243 or .308, when it won’t. The 6.5 Grendel will cost you more to reload and shoot, you will have less choices of bullets, etc, and I personally believe won’t do anything special that others can’t do. Just look at the numbers for yourself, make an educated decision, and don’t buy into all the hype.
That was one kick ass rant!!! Well thought out and backed up with facts. This is exactly the kind of info that I am looking for when weighing my options.
I am planning on buying a dedicated .308 AR, i am just thinking about a heavier caliber upper that will be compatible with my .223 lower.
 
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Discussion Starter #12
That was one kick ass rant!!! Well thought out and backed up with facts. This is exactly the kind of info that I am looking for when weighing my options.
I am planning on buying a dedicated .308 AR, i am just thinking about a heavier caliber upper that will be compatible with my .223 lower.
Lol, thank you very much Sharkbait, I'm glad that you thought it was kick ass. I'm sure there were alot of people here that didn't like the rant because many of them are probably fans of the .260 or 6.5 Grendel. I don't mean to offend those users, the .260 and 6.5 Grendel have their place. I just want new users who might not be aware of the capabilities of these cartridges to have knowledge about these particular calibers, not just that they're "awesome". I'm sure others will help you out on the compatible upper for your .223. I'm curious as to if you're buying an AR-10, why you're just limiting it to something that would work on your .223 lower, since there are uppers that will be able to work with your AR-10 that come in calibers like .243, etc. I like the .204, but I personally (me, maybe not others) prefer the .22-250 over it. The .22-250 shoots every bit as flat and fast, but with heavier bullets, and suffers from about the same rate of throat wear and ammunition is about the same price (only $2 difference per $20).

Just a word about the link that ichy posted. I'm not saying that the man's uppers aren't good or nice, but do a little research on those barrels. Shilen is known for producing very accurate barrels, and lots of BR guys use them. Just realize that some of those guys change their barrels every 500-800 shots (not all of them, but some). Sometimes if they don't like how they're shooting, they change them before that. In the long term, there are many people that believe some of the shilen barrels don't quite last as long as "they should" when you compare them with other barrel makers like Krieger, Lilja, Hart, Bartlein, etc. Typically varmint hunters want a barrel that will hold up to some pretty rapid firing, or at least hold up for quite a long time. Not busting on Shilen, they make fine barrels, I'm just saying do some research on the matter before you jump on top of those.
 
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Discussion Starter #13
Lol, thank you very much Sharkbait, I'm glad that you thought it was kick ass. I'm sure there were alot of people here that didn't like the rant because many of them are probably fans of the .260 or 6.5 Grendel. I don't mean to offend those users, the .260 and 6.5 Grendel have their place. I just want new users who might not be aware of the capabilities of these cartridges to have knowledge about these particular calibers, not just that they're "awesome". I'm sure others will help you out on the compatible upper for your .223. I'm curious as to if you're buying an AR-10, why you're just limiting it to something that would work on your .223 lower, since there are uppers that will be able to work with your AR-10 that come in calibers like .243, etc. I like the .204, but I personally (me, maybe not others) prefer the .22-250 over it. The .22-250 shoots every bit as flat and fast, but with heavier bullets, and suffers from about the same rate of throat wear and ammunition is about the same price (only $2 difference per $20).

Just a word about the link that ichy posted. I'm not saying that the man's uppers aren't good or nice, but do a little research on those barrels. Shilen is known for producing very accurate barrels, and lots of BR guys use them. Just realize that some of those guys change their barrels every 500-800 shots (not all of them, but some). Sometimes if they don't like how they're shooting, they change them before that. In the long term, there are many people that believe some of the shilen barrels don't quite last as long as "they should" when you compare them with other barrel makers like Krieger, Lilja, Hart, Bartlein, etc. Typically varmint hunters want a barrel that will hold up to some pretty rapid firing, or at least hold up for quite a long time. Not busting on Shilen, they make fine barrels, I'm just saying do some research on the matter before you jump on top of those.
I may or may not agree with your input. I haven't gathered enough info to decide yet but I always respect a well thought out position on any subject and facts to back up your position is even better. We all disagree at times but what I like about this site is that we can disagree like adults (most of us) and have a vitrual beer afterwards:cool:

My thinking on a .223 compatible upper was that I could save the money for another upper long before I could save the money for an entire .308 AR. The more I weigh my options I am leaning towards just buying the >308 AR outright at some point.
 
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Discussion Starter #15
I still do NOT understand why so many people are all about the 6.5 Grendel and the .260. I have seen some claims about the 6.5 Grendel and the .260 saying that they’re both superior to the .308 in terms of wind drift, bc, kinetic energy, etc. I have even seen some articles like this http://demigodllc.com/articles/the-c...260-remington/ that are claming things like the .260 even puts the .300 winmag to shame. THIS IS HYPE AND COMPLETE BS. I will talk more about that issue in a sec.

I just wanted to start off this post by saying that I personally believe that there is WAY too much hype behind the 6.5 Grendel, .260 and the 6.8 spc. Now the 6.5 Grendel and the .260 are kind of a medium cartridge between the .308 and the .243. The 6.5 Grendel will fire some of the lighter bullets at a pretty decent speed. Chuck Hawk lists the 6.5 Gendel as firing a 100 grain bullet at around 2800 fps and 2850. 6.5mm Grendel . Some of the heavier bullets like 120 grainers have a muzzle velocity between 2530-2630 fps. (also on chuck hawk’s page). The funny thing about people that claim the 6.5 Grendel is so much better than the .308 don’t take several things into account. The .308 will push a 150 grain bullet between 2980-2700 fps, depending on the load. http://www.pacinfo.com/~dropinsator/chart4.htm#308%20Win . Even the military has loading of the 168 grain bullet that are traveling at least 2680 fps. (a moderate loading, not too hot). This means that the .308 will push a bullet that is 48 grains heavier than the 6.5 Grendel, exactly the same speed. Since they will have a very similar time of flight, because they have a similar speed; this means that IF they were the same weight of bullet, they would have similar wind drift. They do NOT have the same weight of bullet, and therefore, the .308 will have LESS wind drift than the 6.5 Grendel. With some of the lighter bullets, the 6.5 Grendel MIGHT have the same or less wind drift. Because they have very similar velocities, the drop on the bullets will be slightly different, but still pretty close.

There are basically 2 thoughts on wind drift. You can fire a light bullet extremely fast; which means that it has a short time of flight, and therefore less time for the wind to affect the bullet. You can also fire a heavy bullet a little slower; although it will have a longer time of flight, since the projectile is heavier, it will be more difficult for the wind to push it.

The .243 sometimes DOES have less wind drift than the .308, even at long distances because of how much faster the bullets are sometimes moving. People that will claim the 6.5 Grendel, .260 or 6.8 spc have “better long range ballistics” than the .308, etc, are only talking about the very light bullets that the .260, 6.5 Grendel shoot, and comparing them to the heavier bullets that the .308 is shooting. Keep in mind that just because the bullet has less drop, does not mean that it will be a better long range cartridge, it merely means that the bullet will shoot flatter.

Something else that I always hear from the 6.5 Grendel and .260 guys: the high BC bullets of these calibers don’t slow down as quickly as the .30’s (.308, .300 winmag, etc), and they claim that even if they start out at close to the same speed, the BC means at longer range the .30’s aren’t going nearly as fast. For those guys that claim this, I have news for you, There ARE high BC bullets for the .30’s as well, some that have MUCH better BC’s than the 6.5 bullets. If I remember right, Lost River Ballistics (who got bought out by hooker I believe) had a 180 grain bullet that had a BC of something ridiculous like .89-90. I also think it’s funny how the guys that shoot 6.5mm Grendel or .260, like to compare the velocity of those rounds, against the .308 or .300 winmag out of a 24” barrel. You give a .300 winmag or a .308 a 26” barrel and some high BC bullets like 210 VLD’s, 180-190 Lost River, or 155 Scenars, and the 6.5 Grendel and .260 won’t even hold a candle to them. A .300 winmag will push a 180 grain bullet over 3,000 fps, and some of the 210 Bergers around 2700 fps. I assure you that the .260 can’t touch that kind of velocity and weight of bullet, but the guys that are all about the .260 say that it does.

Please realize that I am NOT saying that the 6.5 Grendel or the .260 are bad cartridges. I am merely saying that I believe that some of these cartridges are a fad, and that some of the guys that like to play with these cartridges are making people believe that they are the “cat’s meow”, and people aren’t looking at the ballistics. It’s fine if you want to have a caliber to play with that most everybody else doesn’t, just realize it probably doesn’t do anything special that other calibers can’t. The .260 and 6.5 Grendel both have their place, and I personally believe that’s right in between the .308 and .243. If you do not reload, I would personally stay away from the 6.5 Grendel, even if you do reload, I’d probably still consider the .243 or .243 AI. I would take the .243 AI any day of the week against the 6.5 Grendel, just from how easily you can get components and loads for each. From what I have heard there is only 1-2 makers of brass for the 6.5. There is also a pretty limited choice of bullet weights and manufacturers of them. With the .243 or .308 there are MANY choices of quality brass manufacturers and bullet manufacturers. If you just want to play with the 6.5 Grendel, then go for it, I just don’t want people expecting it to be the greatest thing in the world and beating the socks off of the .243 or .308, when it won’t. The 6.5 Grendel will cost you more to reload and shoot, you will have less choices of bullets, etc, and I personally believe won’t do anything special that others can’t do. Just look at the numbers for yourself, make an educated decision, and don’t buy into all the hype.
it has nothing to do with weight its BC which is related to weight but has other things involved.
if you shot a 7mm bullet at lets say 3000fps and then shot a 308 bullet at 3000 fps the 7mm would have LESS wind drift and less drop and would have a higher ending velocity.
you can shoot a 22-250 at 4000fps but it looses its speed really fast but if you shot a 223 at 2800fps with a high BC bullet the ending velocity would be higher on the 223 (depending on distance to the target. the farther away it is the higher BC bullet with have a higher velocity at the end of its flight even though it started with a lower velocity)

and the 243 is based on a 308 winchester and thats not an ar15 caliber so your comparing apples and oranges

but i would choose a 7mm or a 30 cal bullet for a long range bolt action over the 6.5 any day
but if i wanted a long range ar15 and NOT an ar10 i would choose the 6.5
im not saying the 6.5 is better then a 308 or 300 winchester mag (which i dont think it is)
but i am saying its much better then the 6.8 spc
 
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Discussion Starter #17
I still do NOT understand why so many people are all about the 6.5 Grendel and the .260. I have seen some claims about the 6.5 Grendel and the .260 saying that they’re both superior to the .308 in terms of wind drift, bc, kinetic energy, etc. I have even seen some articles like this http://demigodllc.com/articles/the-c...260-remington/ that are claming things like the .260 even puts the .300 winmag to shame. THIS IS HYPE AND COMPLETE BS.

I am the author of that article. I'm not going to address the 6.5 Grendel at all; however, your characterization of the .260 is inaccurate. I know a thing or two about mid-size 6.5mm calibers-- I've shot over 5000 rounds at long-range targets through the .260REM, 6.5x47 Lapua,and 6.5 Creedmoor over the last 22 months (in addition to 5000 rounds of .308 and approx 2000 of 338 Lapua Magnum over the last few years).

Painting .260 with the same brush as 6.8 SPC and 6.5 Grendel reveals a fundamental misunderstanding about those cartridges. One might argue that 6.5 Grendel and 6.8 SPC are comparable because they were both designed for the AR-15 platform (albeit for different purposes); however, the .260 Remington will not fit in an AR-15. It's a .308 necked down to .260, and in a different cartridge "class" than the 6.5 Grendel or the 6.8 SPC. Putting .260 in the same category as the 6.5 Grendel is like saying .308 and .30-30 are the same- it just doesn't make sense and ignores that 300-500 fps difference (in the case of the .30 cals anyway).

Here is the quote from the article on 260 vs. 300WM,
Compared to the venerable .300 Winchester Magnum's most common load - a 190-grain Sierra MatchKing at 2900 fps - the .260 has about 17% less wind drift and a few clicks less drop. Even though it shoots a 140-grain bullet, it still has 87% of the Magnum's energy at 1000 yards because its slim design yields a much higher ballistic coefficient (BC) value, so it retrains velocity longer. It also has 60% less recoil than the 300.

The .260 Remington blows .308 out of the water. It has 35% less wind drift and about 10 MOA less drop at 1000 yards than the standard 175-grain M118LR load. Despite a 35-grain deficiency in bullet mass, it has 31% more energy because it loses less along the way due to atmospheric drag, hitting 350 fps faster at 1000 yards.
Heck, you can read the article and see the exact numbers coming out of the ballistic calculator that show it:
The Case for .260 Remington: A Better Cartridge For Practical Long-Range Shooting (it's about 1/3rd of the way down)


The .243 sometimes DOES have less wind drift than the .308, even at long distances because of how much faster the bullets are sometimes moving. People that will claim the 6.5 Grendel, .260 or 6.8 spc have “better long range ballistics” than the .308, etc, are only talking about the very light bullets that the .260, 6.5 Grendel shoot, and comparing them to the heavier bullets that the .308 is shooting. Keep in mind that just because the bullet has less drop, does not mean that it will be a better long range cartridge, it merely means that the bullet will shoot flatter.

Here are some facts about .308 and .260 loads:
Code:
_Bullet_           _BC_ _MV_         0     200     400     600     800    1000 | YARDS
243 115 DTAC      0.585 3050 >    0.00    1.92    8.09   19.24   36.28   60.31 | wind (inches)
260 139 Lapua     0.615 2820 >    0.00    2.04    8.58   20.38   38.36   63.65 | wind (inches)
260 123 Scenar    0.540 3050 >    0.00    2.09    8.84   21.15   40.11   67.10 | wind (inches)
308 155 Scenar    0.508 2910 >    0.00    2.38   10.15   24.40   46.58   78.33 | wind (inches)
308 175 SMK       0.51* 2650 >    0.00    2.79   11.94   28.88   55.48   93.43 | wind (inches)
308 168 SMK       0.46* 2700 >    0.00    2.98   12.98   32.15   63.10  108.09 | wind (inches)
243 70 NBT        0.310 3400 >    0.00    3.28   14.45   36.31   72.85  127.47 | wind (inches)

243 115 DTAC      0.585 3050 >   -0.00    1.03    5.01   10.05   16.10   23.35 | drop (moa)
260 139 Lapua     0.615 2820 >   -0.00    1.37    6.07   11.96   18.97   27.34 | drop (moa)
260 123 Scenar    0.540 3050 >   -0.00    1.05    5.11   10.33   16.70   24.47 | drop (moa)
308 155 Scenar    0.508 2910 >   -0.00    1.27    5.89   11.86   19.27   28.48 | drop (moa)
308 175 SMK       0.51* 2650 >   -0.00    1.75    7.52   14.99   24.38   36.21 | drop (moa)
308 168 SMK       0.46* 2700 >   -0.00    1.68    7.39   15.00   24.93   37.99 | drop (moa)
243 70 NBT        0.310 3400 >   -0.00    0.80    4.68   10.45   18.73   30.74 | drop (moa)

243 115 DTAC      0.585 3050 >    3050    2739    2447    2175    1922    1688 | velocity (fps)
260 139 Lapua     0.615 2820 >    2820    2537    2272    2024    1794    1582 | velocity (fps)
260 123 Scenar    0.540 3050 >    3050    2714    2400    2110    1842    1597 | velocity (fps)
308 155 Scenar    0.508 2910 >    2910    2563    2242    1947    1677    1441 | velocity (fps)
308 175 SMK       0.51* 2650 >    2650    2315    2007    1723    1469    1261 | velocity (fps)
308 168 SMK       0.46* 2700 >    2700    2329    1982    1658    1374    1159 | velocity (fps)
243 70 NBT        0.310 3400 >    3400    2786    2246    1775    1384    1116 | velocity (fps)

243 115 DTAC      0.585 3050 >    0.00    0.21    0.44    0.70    0.99    1.33 | time (sec)
260 139 Lapua     0.615 2820 >    0.00    0.22    0.47    0.75    1.07    1.43 | time (sec)
260 123 Scenar    0.540 3050 >    0.00    0.21    0.44    0.71    1.01    1.36 | time (sec)
308 155 Scenar    0.508 2910 >    0.00    0.22    0.47    0.76    1.09    1.48 | time (sec)
308 175 SMK       0.51* 2650 >    0.00    0.24    0.52    0.84    1.22    1.66 | time (sec)
308 168 SMK       0.46* 2700 >    0.00    0.24    0.52    0.85    1.25    1.73 | time (sec)
243 70 NBT        0.310 3400 >    0.00    0.20    0.44    0.74    1.12    1.61 | time (sec)
Note that I've first displayed the wind drift, which is the most important long-range attribute (since long-range misses are 90% due to windage error), and sorted the loads from best to worst in terms of wind drift at 1000 yards.

In direct contradiction to your claim that "
are only talking about the very light bullets that the .260, 6.5 Grendel shoot, and comparing them to the heavier bullets that the .308 is shooting. ", note that it is the highest-BC bullets in the 260 which perform best at long range (which often means the heaviest but not always). High-BC bullets lose velocity at a slower rate and have less wind drift.

Something else that I always hear from the 6.5 Grendel and .260 guys: the high BC bullets of these calibers don’t slow down as quickly as the .30’s (.308, .300 winmag, etc), and they claim that even if they start out at close to the same speed, the BC means at longer range the .30’s aren’t going nearly as fast. For those guys that claim this,

You can see this in the data. The 260/139gr starts at 2820 fps but slows to 1582 at 1000 yards. The 308/155 starts at 2910 but slows to 1441 at 1000 yards.
I have news for you, There ARE high BC bullets for the .30’s as well, some that have MUCH better BC’s than the 6.5 bullets. If I remember right, Lost River Ballistics (who got bought out by hooker I believe) had a 180 grain bullet that had a BC of something ridiculous like .89-90.
If you ignore lathe-turned bullets which cost in the range of $2.0 per bullet and stick to conventional OTM designs like the SMK, Scenar, and Berger VLD, you have to step up to a 210gr VLD to exceed 0.60 BC in .30 caliber. If you could shoot this at 2450 fps, it would have almost the same wind drift @ 1000 as the 155gr Lapua Scenar shot at 2910 fps from the 308 (actually 3.5% less); however, because of its low muzzle velocity it has 31% more drop and an increased "drop rate".

If we compare this "high BC" but heavy load in 308 to the 260/139, here's what we get:
Code:
_Bullet_           _BC_ _MV_         0     200     400     600     800    1000 | YARDS
260 139 Lapua     0.615 2820 >    0.00    2.04    8.58   20.38   38.36   63.65 | wind (inches)
308 210VLD        0.631 2450 >    0.00    2.42   10.21   24.31   45.81   75.71 | wind (inches)

260 139 Lapua     0.615 2820 >   -0.00    1.37    6.07   11.96   18.97   27.34 | drop (moa)
308 210VLD        0.631 2450 >   -0.00    2.13    8.57   16.51   26.01   37.34 | drop (moa)

260 139 Lapua     0.615 2820 >    2820    2537    2272    2024    1794    1582 | velocity (fps)
308 210VLD        0.631 2450 >    2450    2197    1960    1740    1539    1363 | velocity (fps)

260 139 Lapua     0.615 2820 >    0.00    0.22    0.47    0.75    1.07    1.43 | time (sec)
308 210VLD        0.631 2450 >    0.00    0.26    0.55    0.87    1.24    1.65 | time (sec)

260 139 Lapua     0.615 2820 >    0.04   -0.05   -0.18   -0.33   -0.52   -0.76 | drop per yard (inches)
308 210VLD        0.631 2450 >    0.05   -0.08   -0.24   -0.45   -0.71   -1.04 | drop per yard (inches)
Woops. The 260 blows it out of the water. At 1000 yards: 16% less wind drift; 27% less drop; 16% more impact velocity; 14% less flight time; 27% less drop rate; and 42% less recoil (ie, FRE).

Continued in next post
 
G

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Discussion Starter #18
I also think its funny how the guys that shoot 6.5mm Grendel or .260, like to compare the velocity of those rounds, against the .308 or .300 winmag out of a 24 barrel. You give a .300 winmag or a .308 a 26 barrel and some high BC bullets like 210 VLDs, 180-190 Lost River, or 155 Scenars, and the 6.5 Grendel and .260 wont even hold a candle to them. A .300 winmag will push a 180 grain bullet over 3,000 fps, and some of the 210 Bergers around 2700 fps. I assure you that the .260 cant touch that kind of velocity and weight of bullet, but the guys that are all about the .260 say that it does.
The reason is that the .308 case hits the sweet spot for case capacity for bore size ratio with a .264" bullet, not a .308 bullet. This is expressed in the data because you cannot get those high-BC .30 caliber bullets going fast enough from a .308; whereas the 6.5mm bullets are cooking along at a good clip. If you step up to the 300WM case size, you start to be able to take advantage of them.

If you can get a 210gr VLD going fast enough, it can break even or just beat the best 260 loads. In my comparison above, I was using my load of the 139gr @ 2820 fps. I know 260 shooters who are using the 140gr VLD at 2860 fps which provides identical wind and drop performance to a 210gr VLD shot at 2850 fps from a 300WM. But now we're comparing a a moderate to hot load in a magnum case burning 80 grains of powder to a short-action cartridge burning about 40. The 300WM load has 2.2x the recoil and gives exactly the same trajectory performance.
Just look at the numbers for yourself, make an educated decision, and dont buy into all the hype.
By all means... look at the numbers.

:cool:
 
G

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Discussion Starter #20
.........The reason is that the .308 case hits the sweet spot for case capacity for bore size ratio with a .264" bullet, not a .308 bullet. This is expressed in the data because you cannot get those high-BC .30 caliber bullets going fast enough from a .308; whereas the 6.5mm bullets are cooking along at a good clip. If you step up to the 300WM case size, you start to be able to take advantage of them.

If you can get a 210gr VLD going fast enough, it can break even or just beat the best 260 loads. In my comparison above, I was using my load of the 139gr @ 2820 fps. I know 260 shooters who are using the 140gr VLD at 2860 fps which provides identical wind and drop performance to a 210gr VLD shot at 2850 fps from a 300WM. But now we're comparing a a moderate to hot load in a magnum case burning 80 grains of powder to a short-action cartridge burning about 40. The 300WM load has 2.2x the recoil and gives exactly the same trajectory performance.
By all means... look at the numbers.

:cool:

Howdy Zak,

I’m glad to see that you were actually on the forum and are actually talking about the article. I believe that some of what I have said has been a bit misunderstood, as I have probably misunderstood some of what you have written. I have seen the article that you have written being used to totally “disprove” the use of the magnum cartridges for long distance shooting. I agree that the numbers on the .260 are pretty impressive, and I would definitely favor the .260 over many of the other cartridges that I previously discussed. I will start off by saying that I am not a fan of the .308, and only mentioned it in context of that the .260 doesn’t beat the pants off of the .308. I am fully aware of the differences in the platforms that the 6.5 Grendel, 6.8 spc, and the .260 and their differences, I merely mentioned these calibers because on this forum and a few others they are all mentioned to have “the best long range ballistics” and some data is over looked.

When you talk about comparing the 190 grain sierra match king in a .300 winmag at 2900 fps, I consider that to be quite a moderate loading. Most of us that shoot the .300 win mag are aware that the benefits and the true pay off to shooting the caliber and suffering the downfall over the over bore is using the some of the heavier bullets and really pushing them. I have no doubt about the calculations you make with the numbers you provide, I merely don’t think that it’s comparing apples to apples either. If you are talking about using some of the heavier or best BC bullets of the .260, then it would also seem a valid comparison to compare the heavier bullets in the .300 win mag and it’s high bc bullets as well. I agree with you, that the .260 overall probably beats the heck out of the .308 as a long distance cartridge, but I would say the same for the .243. Sure it doesn’t quite deliver the kinetic energy that the .308 does, or even the .260 but it still has phenomenal ballistics. I did not have any intention to say that the .260 is useless or not a good caliber, I merely intended to get the point across that there are other widely accepted cartridges that will have similar performance to the .260. You could get a bit more velocity out of the .243 and have a lighter bullet and lighter recoil, and probably the same wind drift with less recoil. It’s just taking what you did to the .308, doing it to the .260 and taking it a step further to the .243. Now I do realize that when you want to talk about “optimum” bc, it definitely is favored towards the 6.5 and 6.8mm bullets over the 6mm, but I’m was merely saying that other cartridges will have similar numbers for the conventional user and be much more accessible. You show yourself in the numbers between the .243 and the .260 that the .243 has more velocity, and less wind drift than the .260 and it shoots flatter. I was merely stating that fact again to other users, that the if you want something that shoots flatter and has less wind drift than the .308, go with a .243 they’re easy to come by and you can buy amazing brass and have tons of bullets choices and the benefits (aside from some of the kinetic energy) that the .260 delivers.

I agree with you 100% that in terms of wind drift and how flat they shoot, the .260 beats the crap out of the .308. If we really get down to it though, so do lots of other cartridges because the .308 is kind of “dragging ass” (pardon my language). You mention ignoring the lathe turned high BC bullets for the .30, so let’s consider that fact for a minute (we’ll come back to it). I know quite a few fellas that shoot the 210 VLD quite a good clip over 2450, so it’s not like it’s some super hot load. Sure it beats your shoulder up, but the bullet delivers more kinetic energy on target and if it’s going over 2450, like say 2700 fps or a bit more from a .300 win mag, it would have less wind drift than the .260. It’s funny to me that you want to ignore the lathe turned bullets and talk about long distance shooting. If you’re truly being serious about long range ballistics and talking about which high BC bullet will shoot better long distance, why would you discount the lathe turned bullets of the .30’s? You and I both know that shooting long range consistency costs a lot of money, so why would you spare the price difference between lathe turned bullets if that’s what gets you there consistently? It would appear to me that comparing apples to apples would be comparing the highest BC bullets of the .300 win mag at their moderate or even hot loadings and comparing it to the highest BC bullets of the .260 and it’s moderate and hot loadings. That would give us a pretty good idea of what the maximum of the .300 win mag is and what the maximum of the .260 is. I would much rather this approach than comparing a load that’s moving a pretty good clip with the best bullets available from the .260 and comparing it to a load that’s maybe only 85% of what the .300 win mag will do. Then saying well, the .260 has 17% less wind drift and 87% of the kinetic energy. People that shoot the .300 win mag seriously, shoot the heavy bullets and they shoot them hot, that’s what they got the .300 win mag for. They shoot the light bullets to play around, varmint with, and keep them somewhat up close, not to push 1K or more.

So the .260 blows the .308 out of the water, ok, I’ll go with you on that. The .260 still doesn’t blow the .300 win mag out of the water using the heavier bullets (what it was designed for) and pushing the loads a little. So if it then doesn’t do what the .300 win mag will do at a distance, well then let’s take thing in a little closer, and the .243 will stay right up there with the .260. Sure the .260 has less recoil, that’s a given because it’s a lighter load, and it still won’t have the same kinetic energy as the .300 win mag. I agree with you that the .260 has its own place and it does pretty dang good at long range. I believe that if you’re being serious about it though, you’re going to use a larger and heavier projectile, and you’re going to just deal or compensate for the eating you take from that magnum. If you want to keep things in a little closer and are shooting paper (so you’re not worried about the kinetic energy) the .243 put up great numbers, and is MUCH more conventional. You said it yourself that the .300 win mag’s best loads will beat the bets .260 loads. I suppose that it’s like anything else, it’s all a preference thing and I’d rather have the extra kinetic energy and the heavier projectile. When you add in lathe turned projectiles into the equation, the .260 doesn’t measure up, and in the long range game, not many people spare many expenses if they’re serious about it. Why would you not spend the extra money to make your hits, flatter with less wind drift?

The main point that I was trying to get across to most of the people on the forum is that there are more economical and reliable cartridges that will do what they need it do for A LOT less. Most of these guys aren’t rolling their own, and aren’t going to be able to deal with the .260 the way they would the .243. Realistically, most of them won’t even shoot seriously over 600 yards either. The ones that will, the .260 would probably fit them a little better, just like other cartridges might. For the practicality reason, and the benefits that most of these guys would get, the .243 is all they need if they want a lighter faster bullet. The .243 has at least 3 times as many choices when it comes to ammunition, and they’re usually WAY WAY cheaper. ALL of the ammunition for the .260 is around $1.50 a shot, with a lot of it being $2 a shot. You get onto the price of a .300 win mag and some of late turned bullets, but you could use the same argument against the .260 in favor of the .243 when it came to price. Continued in next post.
 
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