6.5 grendel-.260 rem-6.5 creedmoor-6.5x47 lapua which is best for a sniper platform

grprecon · May 24, 2010, 08:31 PM

I'm thinking of building an semi auto ar platform sniper rifle in one of the four calibers

I'm fully aware of its the shooters capabilities with the rifle,
but id like to know which one of the 4 rounds will deliver optimal performance by itself in the following categories
>accuracy
>effective range
>stopping power
hypothetically, which caliber would you think the us military would choose for a long range precision semi auto round to replace the 7.62x51 nato round,

i know the military probably wont replace the 7.62x51 nato with any of these calibers but they are with the .338. i just asked to understand which is the best caliber best suited for sniping past 800yrds

im looking to build an ar-10 with any where from a 18-24inch free float fluted match barrel, match trigger, possibly left side charging handle, with tons of magpul furniture, and don't mind the weight really

Zak Smith · May 24, 2010, 08:44 PM

The Grendel was designed to fit in AR-15. The others will only fit an AR-10 size receiver. The ballistics of the Grendel significantly lag the last 3.

Here is a comparison of the last 3

article | 6.5mm Shootout: .260 Remington vs. 6.5x47 Lapua vs. 6.5 Creedmoor

The US military is not likely to change to any of these. The next sniper rifle will be a .338 and the 7.62 NATO is too entrenched to replace.

Hawkeye_FH · May 24, 2010, 08:45 PM

If I am not mistaken the Grendel has considerably less case capacity than the others. The other three are popular in long distance shooting sports and will reach out past 1000 yards. Wait for Zak Smith to come along, he has alot of experience with the 6.5s and some very good articles comparing them.

Edit: dang he beat me to it! LOL!

thesheepdog · May 25, 2010, 08:20 AM

6.5 Creedmor and the others you listed are for an AR-10 build. The Grendel will put out a little over 500 ft/lbs at 1000 yards and carries about 450 ft/lbs at 1200. At 1000 yards the Grendel has more velocity, a flatter trajectory and more energy than the 7.62 NATO. The .260 is just a .308 necked down to a .264 projectile. It has slightly more energy than the Grendel.

It just depends on what you want to build. AR-15, or AR-10. And do you want low recoil, or a bit higher recoil with the .260, 6.5 creedmor and the 6.5X47mm? You'll be able to carry more ammo on a Grendel. 26 rounds comapred to 20 in the other 3.

I am building me a Grendel as i speak.

Longdayjake · May 25, 2010, 09:29 AM

I don't really know what I would do in your situation. I much prefer the ar15 weight and portability to the ar10, but if I was wanting to do some extreme long range shooting I would want the cartridge with the most case capacity. I have a 6.5 grendel and it is working very well for my needs, but I rarely shoot past 600 yards and even rarely shoot to 600 yards. I know that there are guys getting small groups at 1000 yards with it so if all you wanted to go was 1000 I would say go for the grendel.

beardenbc · May 25, 2010, 10:27 AM

All depends on how much weight you're willing to carry. If you want to pack light go with the grendel. If you can take the extra weight, go with the creedmoor or .260.

Zak Smith · May 25, 2010, 11:24 AM

Couple notes based on prior posts:

1. 6.5 Grendel does not exceed all .308 loads. It can probably exceed military ball ammo, but it is unlikely to beat a 155gr Lapua fired at an equal barrel length .308.

2. Ballistics of .260 significantly exceed the ballistics of the 6.5 Grendel. This should be no surprise to anyone based solely on the difference in case capacity: almost 50% more than the small Grendel case.

AA quotes a 123gr Scenar at 2630 fps from a 24" barrel, or a 130gr VLD at 2492 fps, and there is no data in that table for a 140-gr-class bullet (but let's say 2400 fps to be liberal). A 24" .260 will shoot a 140gr class bullet at 2900 fps, a 123gr at approx 3150 fps.

Here's the long range data for those loads, and a 24" .308 155gr match load for comparison

Code:

_Bullet_           _BC_ _MV_         0     200     400     600     800    1000    1200 | YARDS
308 155 Scenar    0.508 2930 >    0.00    2.27    9.66   23.18   44.10   73.97  114.19 | wind (inches)
260 139           0.615 2900 >    0.00    1.89    7.93   18.79   35.26   58.34   89.09 | wind (inches)
260 123           0.545 3150 >    0.00    1.90    8.03   19.15   36.15   60.21   92.69 | wind (inches)
6.5 123           0.545 2630 >    0.00    2.46   10.44   25.00   47.44   79.05  120.82 | wind (inches)
6.5 139           0.615 2400 >    0.00    2.47   10.42   24.80   46.70   77.05  116.50 | wind (inches)

308 155 Scenar    0.508 2930 >   -0.00    0.94    5.30   11.03   18.12   26.87   37.72 | drop (moa)
260 139           0.615 2900 >   -0.00    0.94    5.18   10.58   17.02   24.64   33.70 | drop (moa)
260 123           0.545 3150 >   -0.00    0.63    4.20    8.92   14.64   21.56   29.96 | drop (moa)
6.5 123           0.545 2630 >   -0.00    1.46    6.97   14.05   22.71   33.28   46.21 | drop (moa)
6.5 139           0.615 2400 >   -0.00    1.97    8.56   16.80   26.66   38.44   52.49 | drop (moa)

GeauxTide · May 25, 2010, 11:58 AM

He is the 6.5 Master.

Jimro · May 25, 2010, 02:28 PM

If you can get the bullet on target, usually there is plenty of energy remaining to do the job.

Currently the US Army is looking long and hard at the 300 Win Mag. A new contract for Mk248 upped the bullet weight to a 220 gr VLD at 2850 fps gives a viable 1200 meter solution, and further depending on conditions.

As far as the 6.5's go, they all work.

Jimro

5 Finders · June 1, 2010, 07:04 AM

.338 built in a Accuracy International weapon, got me out of the brown stinky stuff! if not a 6.5 gren with 160g projectiles is my way.

ronsyre · June 10, 2012, 03:20 AM

The only way to honestly answer this question is you must first specify the platform you intend to build on.If you intend to build on an AR-15 platform and wanted maximum performance I would build around a 6mm class of ammunition I am thinking along the lines of 6mm AR turbo 40, a fast turn barrel something like a 1in7 and heavy bullets 100 to 115 grain.A custom affair and costly.

If you are willing to go to the AR-10 size platform think about 6.5x284 if useing a .473 bolt face or a 7mm WSM if .534 bolt face. Both bolts are or were commercially available from Armalite. Again a cosely affair.

To get cost to a reasonable level I would build the 6.5 Grendel. This should be able to be done nicely for around $1000.

The custom AR-10 platform rifles will be in the $2000 to $3000 price range depending on how extreme you can afford.

There are also some WSSM AR-15 rifles around these will push 6mm 105's to 3100 F/S or .25 cal 120'S to about 3000 F/S.

AR rifles are like Pringles one is never enough.

Best of luck,
Ron

Doyle · June 10, 2012, 06:30 AM

I've always thought that one of the deterrents to using a .260 in an AR-type platform was the overall length. To get the most out of the .264 bullet you need long ones and unless you seat them deep, those long bullets would catch on the magazine. Am I wrong?

mehavey · June 10, 2012, 08:34 AM

This is a systems-of-systems(-of-systems) problem.

If you are going to be a one-shot/one-kill sniper as sole mission, take the 300Win Mag in a bolt action and team w/ a spotter w/ an M4 to keep you alive if things get close-quarter hairy. Sorta as has been done for a looooog time now in various guises. (Or just go for broke hump and a 338 Lapua/50 Barrett along w/ that spotter. The options are endless once weight doesn't matter.)

If the options aren't endless, weight does matter (including the ammo loadout), and if you want a balanced weapons system acting as a quarterhorse at all ranges in a combat loadout based on the existing AR dimensions/action, ...take the Grendel. It gets the best possible ballistics out of that action.

(My 2₵ of course)

tobnpr · June 10, 2012, 01:11 PM

Quote:

if not a 6.5 gren with 160g projectiles is my way.

140 grain is the practical max bullet weight for the Grendel.

tahunua001 · June 10, 2012, 01:40 PM

I would say that the 260 remington is probably the best but I've never heard of an AR(either 15 or 10) chambered in that round.

PawPaw · June 10, 2012, 02:24 PM

Quote:

Originally Posted by tahunua001

I would say that the 260 remington is probably the best but I've never heard of an AR(either 15 or 10) chambered in that round.

Armalite makes one. LINKY HERE.

So does DPMS. LINKY HERE

tobnpr · June 10, 2012, 03:22 PM

Yep. The DPMS Panther in .260 has been around for a while. Pretty smoking deal, though clearly not a match rifle, for a grand...

Doyle · June 10, 2012, 03:27 PM

Wasn't there also a .260 barrel made for the Rem R25?

Jimro · June 10, 2012, 03:45 PM

Wow, this is a blast from the past.

The Army did go to a 300 Win Mag solution, but in a twist got "switch barrel" capability to go from 308 win up to 338 Lapua from the same platform. NSW Crane pushed out a 220gr SMK loading to go with it, replacing the old 190gr SMK loading for A191 DODIC.

If I were going to answer this question today, it still doesn't matter which 6.5 you choose, if the bullet hits the target there is usually enough energy remaining to do the job.

If it were me? I'd go with the Creedmoor. Personal choice, I hate trimming brass and the shoulder angle of the Creedmoor brass means less growth over the 260 Rem. From a semi-auto the "4 reloads and chuck it" school of thought has a lot of good history behind it.

Jimro

Mr. Dusty · August 10, 2012, 12:39 AM

This does indeed look like one of those threads that just won't ever die LOL. I haven't posted on this particular forum as much as I'd like but I've seen plenty just like it everywhere else.

It seems that the question is still quite relevant; in all honesty I can't really say I'd pick any of them just for the sake of doing so. I think a more relevant question would be which of the stated calibers is best for X purposes, it's pros and cons, and ultimately any other miscellaneous information.

6.5x284: I really like this cartridge due to how incredibly accurate it can be loaded as well as it's dominant power over the rest of the aforementioned 6.5's. One thing to consider with this round though is it's OAL in the neighborhood of 82mm give or take. This means it's not going to fit into an AR-10 platform nor will it fit into an AR-15. You could possibly get it to work in a customized 84mm semi-automatic rifle but due to very mild taper (if any) and it's neck being more akin to a BR rifle than a tactical...feeding could be a problem. It absolutely dominates the rest in terms of power, it's accuracy holds legendary status in F-class shooting...but you're probably best off using this rifle in a bolt action rifle.

6.5 Grendel: I'll have to admit that I'm not a big fan of this particular incarnation of the .264, but it does seem to have found itself a loyal following; particularly if you like Ar-15s or other rifles with the "super short" chamber. It's power is considerably far behind the rest of the pack...but if it's anything like the 6.5x55mm or 6.5 Arisaka rounds in the same league, I'd imagine it's probably quieter. I could also imagine there are times where you might want more mild velocities for hunting purposes so you can eat up to the hole, reduced velocities to a point can actually improve penetration. Overall this is the round you'd want for an AR-15 platform or similar light weaponry. It's got the least recoil of the others and can still be used on larger game due to the 6.5mm's density and consistency.

260 Rem: This one is probably truly smack dab in the middle. The .308 parent case makes brass almost impossible to run out of. It may be a pain to form your own brass from .308 or .243, but all in all having a cartridge that can utilize so many types of extremely common brass is an advantage that should -never- be taken lightly. It's rim and shape make it superb for an Ar-10 project, or any short length rifle for that matter. Heck, the Remington 74XX series made .260's, as did the 7600 pump if I recall correctly. This is the round you'll want if you're looking for a multi-purpose 6.5mm. it's capable of target shooting, it's capable of hunting with, shtf/zombies, and the amount of rifles you could customize into this caliber is nothing short of inspiring.

6.5x47mm Lapua: Now I have to admit that I have no experience with this particular round...but it's design seems to be aimed at a very specific purpose. Unlike the .260 Rem the case is supposedly a bit more efficient, but what is certain is that it's shorter brass allows it to seat bullets with large, competition style BC slugs while still fitting in a magazine. It's design purportedly reduces barrel wear, and even though it was designed for competitions it's tactical advantages really make it shine in terms of the rounds capable of competing. This is the type of round you'd want if you're specifically looking for a highly accurate tactical rifle, or a round that won't burn up match barrels like the short and fat PPC/BR type rounds.

6.5 Creedmoor: Honestly I don't see enough evidence that would suggest this cartridge is anything other than another option for match or tactical/hunting situations. It's not bad but it doesn't seem to do anything significant enough to be touted over the former two rounds. It's another round you can easily swap into an AR-10/.308 length chamber easily. The Lapua is slightly less powerful than the .260 and Creedmoor, and perhaps more expensive. The .260 uses common brass that some would say is inferior to the Creedmoor's design, and the Creedmoor has -slightly- more room for a longer/bigger slug. So, all in all, This round is what you'd want if you aren't impressed with the .260 or the 6.5x47mm, or just want to have something more unique than a necked down .308.

I hope I haven't been too entirely rambly (though I'm sure I have), as well as hope I've helped those who might still be wondering which they want, if any of them are better or worse for X or Y situations, so forth so on.

Also; do remember that the 6.5x55mm is still a very viable choice that exceeds the power of the .260. For those who like old military rifles (especially modified) the 6.5x50mm Arisaka's power is on par with the 6.5mm Grendel.

May 24, 2010, 08:31 PM	#1
grprecon Member Join Date: April 12, 2010 Posts: 20	6.5 grendel-.260 rem-6.5 creedmoor-6.5x47 lapua which is best for a sniper platform I'm thinking of building an semi auto ar platform sniper rifle in one of the four calibers I'm fully aware of its the shooters capabilities with the rifle, but id like to know which one of the 4 rounds will deliver optimal performance by itself in the following categories >accuracy >effective range >stopping power hypothetically, which caliber would you think the us military would choose for a long range precision semi auto round to replace the 7.62x51 nato round, i know the military probably wont replace the 7.62x51 nato with any of these calibers but they are with the .338. i just asked to understand which is the best caliber best suited for sniping past 800yrds im looking to build an ar-10 with any where from a 18-24inch free float fluted match barrel, match trigger, possibly left side charging handle, with tons of magpul furniture, and don't mind the weight really Last edited by grprecon; May 25, 2010 at 04:17 PM.

May 24, 2010, 08:44 PM	#2
Zak Smith Senior Member Join Date: December 12, 1999 Location: Fort Collins, Colorado, USA Posts: 2,682	The Grendel was designed to fit in AR-15. The others will only fit an AR-10 size receiver. The ballistics of the Grendel significantly lag the last 3. Here is a comparison of the last 3 article \| 6.5mm Shootout: .260 Remington vs. 6.5x47 Lapua vs. 6.5 Creedmoor The US military is not likely to change to any of these. The next sniper rifle will be a .338 and the 7.62 NATO is too entrenched to replace. __________________ Zak Smith . DEMIGOD LLC . THUNDER BEAST ARMS CORP . COLORADO MULTI-GUN *My PM inbox full? Send e-mail instead.*

May 25, 2010, 08:20 AM	#4
thesheepdog Senior Member Join Date: May 12, 2010 Location: DFW Texas Posts: 1,996	6.5 Creedmor and the others you listed are for an AR-10 build. The Grendel will put out a little over 500 ft/lbs at 1000 yards and carries about 450 ft/lbs at 1200. At 1000 yards the Grendel has more velocity, a flatter trajectory and more energy than the 7.62 NATO. The .260 is just a .308 necked down to a .264 projectile. It has slightly more energy than the Grendel. It just depends on what you want to build. AR-15, or AR-10. And do you want low recoil, or a bit higher recoil with the .260, 6.5 creedmor and the 6.5X47mm? You'll be able to carry more ammo on a Grendel. 26 rounds comapred to 20 in the other 3. I am building me a Grendel as i speak. __________________ Krav Maga/Judo Qualified Rifleman/Marksmanship Instructor/Lic. Medic "There is therefore now no condemnation to those who are in Christ Jesus, who do not walk according to the flesh, but according to the Spirit" Romans 8:1

May 25, 2010, 09:29 AM	#5
Longdayjake Senior Member Join Date: August 11, 2009 Posts: 619	I don't really know what I would do in your situation. I much prefer the ar15 weight and portability to the ar10, but if I was wanting to do some extreme long range shooting I would want the cartridge with the most case capacity. I have a 6.5 grendel and it is working very well for my needs, but I rarely shoot past 600 yards and even rarely shoot to 600 yards. I know that there are guys getting small groups at 1000 yards with it so if all you wanted to go was 1000 I would say go for the grendel. __________________ If you need bullets for reloading give my website a look. www.rmrbullets.com

May 25, 2010, 11:24 AM	#7
Zak Smith Senior Member Join Date: December 12, 1999 Location: Fort Collins, Colorado, USA Posts: 2,682	Couple notes based on prior posts: 1. 6.5 Grendel does not exceed all .308 loads. It can probably exceed military ball ammo, but it is unlikely to beat a 155gr Lapua fired at an equal barrel length .308. 2. Ballistics of .260 significantly exceed the ballistics of the 6.5 Grendel. This should be no surprise to anyone based solely on the difference in case capacity: almost 50% more than the small Grendel case. AA quotes a 123gr Scenar at 2630 fps from a 24" barrel, or a 130gr VLD at 2492 fps, and there is no data in that table for a 140-gr-class bullet (but let's say 2400 fps to be liberal). A 24" .260 will shoot a 140gr class bullet at 2900 fps, a 123gr at approx 3150 fps. Here's the long range data for those loads, and a 24" .308 155gr match load for comparison Code: _Bullet_ _BC_ _MV_ 0 200 400 600 800 1000 1200 \| YARDS 308 155 Scenar 0.508 2930 > 0.00 2.27 9.66 23.18 44.10 73.97 114.19 \| wind (inches) 260 139 0.615 2900 > 0.00 1.89 7.93 18.79 35.26 58.34 89.09 \| wind (inches) 260 123 0.545 3150 > 0.00 1.90 8.03 19.15 36.15 60.21 92.69 \| wind (inches) 6.5 123 0.545 2630 > 0.00 2.46 10.44 25.00 47.44 79.05 120.82 \| wind (inches) 6.5 139 0.615 2400 > 0.00 2.47 10.42 24.80 46.70 77.05 116.50 \| wind (inches) 308 155 Scenar 0.508 2930 > -0.00 0.94 5.30 11.03 18.12 26.87 37.72 \| drop (moa) 260 139 0.615 2900 > -0.00 0.94 5.18 10.58 17.02 24.64 33.70 \| drop (moa) 260 123 0.545 3150 > -0.00 0.63 4.20 8.92 14.64 21.56 29.96 \| drop (moa) 6.5 123 0.545 2630 > -0.00 1.46 6.97 14.05 22.71 33.28 46.21 \| drop (moa) 6.5 139 0.615 2400 > -0.00 1.97 8.56 16.80 26.66 38.44 52.49 \| drop (moa) __________________ Zak Smith . DEMIGOD LLC . THUNDER BEAST ARMS CORP . COLORADO MULTI-GUN *My PM inbox full? Send e-mail instead.*

May 24, 2010, 08:45 PM	#3
Hawkeye_FH Member Join Date: October 21, 2008 Location: Central Kentucky Posts: 61	If I am not mistaken the Grendel has considerably less case capacity than the others. The other three are popular in long distance shooting sports and will reach out past 1000 yards. Wait for Zak Smith to come along, he has alot of experience with the 6.5s and some very good articles comparing them. Edit: dang he beat me to it! LOL!

May 25, 2010, 10:27 AM	#6
beardenbc Senior Member Join Date: January 21, 2008 Location: Las Vegas Posts: 189	All depends on how much weight you're willing to carry. If you want to pack light go with the grendel. If you can take the extra weight, go with the creedmoor or .260.

May 25, 2010, 11:58 AM	#8
GeauxTide Senior Member Join Date: April 20, 2009 Location: Helena, AL Posts: 4,424	Pay Close Attention to ZAK He is the 6.5 Master.

May 25, 2010, 02:28 PM	#9
Jimro Senior Member Join Date: October 18, 2006 Posts: 7,097	If you can get the bullet on target, usually there is plenty of energy remaining to do the job. Currently the US Army is looking long and hard at the 300 Win Mag. A new contract for Mk248 upped the bullet weight to a 220 gr VLD at 2850 fps gives a viable 1200 meter solution, and further depending on conditions. As far as the 6.5's go, they all work. Jimro __________________ Machine guns are awesome until you have to carry one.

June 1, 2010, 07:04 AM	#10
5 Finders Junior Member Join Date: May 30, 2010 Location: Australia Posts: 7	best round .338 built in a Accuracy International weapon, got me out of the brown stinky stuff! if not a 6.5 gren with 160g projectiles is my way.

June 10, 2012, 03:20 AM	#11
ronsyre Junior Member Join Date: December 14, 2010 Location: Pleasant Prairie Wisconsin Posts: 1	The only way to honestly answer this question is you must first specify the platform you intend to build on.If you intend to build on an AR-15 platform and wanted maximum performance I would build around a 6mm class of ammunition I am thinking along the lines of 6mm AR turbo 40, a fast turn barrel something like a 1in7 and heavy bullets 100 to 115 grain.A custom affair and costly. If you are willing to go to the AR-10 size platform think about 6.5x284 if useing a .473 bolt face or a 7mm WSM if .534 bolt face. Both bolts are or were commercially available from Armalite. Again a cosely affair. To get cost to a reasonable level I would build the 6.5 Grendel. This should be able to be done nicely for around $1000. The custom AR-10 platform rifles will be in the $2000 to $3000 price range depending on how extreme you can afford. There are also some WSSM AR-15 rifles around these will push 6mm 105's to 3100 F/S or .25 cal 120'S to about 3000 F/S. AR rifles are like Pringles one is never enough. Best of luck, Ron __________________ Ronald Syre

June 10, 2012, 06:30 AM	#12
Doyle Senior Member Join Date: June 20, 2007 Location: Rainbow City, Alabama Posts: 7,167	I've always thought that one of the deterrents to using a .260 in an AR-type platform was the overall length. To get the most out of the .264 bullet you need long ones and unless you seat them deep, those long bullets would catch on the magazine. Am I wrong?

June 10, 2012, 08:34 AM	#13
mehavey Senior Member Join Date: June 17, 2010 Location: Virginia Posts: 6,894	This is a systems-of-systems(-of-systems) problem. If you are going to be a one-shot/one-kill sniper as sole mission, take the 300Win Mag in a bolt action and team w/ a spotter w/ an M4 to keep you alive if things get close-quarter hairy. Sorta as has been done for a looooog time now in various guises. (Or just go for broke hump and a 338 Lapua/50 Barrett along w/ that spotter. The options are endless once weight doesn't matter.) If the options aren't endless, weight does matter (including the ammo loadout), and if you want a balanced weapons system acting as a quarterhorse at all ranges in a combat loadout based on the existing AR dimensions/action, ...take the Grendel. It gets the best possible ballistics out of that action. (My 2₵ of course) Last edited by mehavey; June 10, 2012 at 10:03 AM.

June 10, 2012, 01:40 PM	#15
tahunua001 Senior Member Join Date: July 21, 2011 Location: Idaho Posts: 7,839	I would say that the 260 remington is probably the best but I've never heard of an AR(either 15 or 10) chambered in that round. __________________ ignore my complete lack of capitalization. I still have no problem correcting your grammar. I never said half the stuff people said I did-Albert Einstein You can't believe everything you read on the internet-Benjamin Franklin

June 10, 2012, 03:22 PM	#17
tobnpr Senior Member Join Date: August 1, 2010 Location: Tampa Bay Posts: 4,556	Yep. The DPMS Panther in .260 has been around for a while. Pretty smoking deal, though clearly not a match rifle, for a grand...

June 10, 2012, 03:27 PM	#18
Doyle Senior Member Join Date: June 20, 2007 Location: Rainbow City, Alabama Posts: 7,167	Wasn't there also a .260 barrel made for the Rem R25?

June 10, 2012, 03:45 PM	#19
Jimro Senior Member Join Date: October 18, 2006 Posts: 7,097	Wow, this is a blast from the past. The Army did go to a 300 Win Mag solution, but in a twist got "switch barrel" capability to go from 308 win up to 338 Lapua from the same platform. NSW Crane pushed out a 220gr SMK loading to go with it, replacing the old 190gr SMK loading for A191 DODIC. If I were going to answer this question today, it still doesn't matter which 6.5 you choose, if the bullet hits the target there is usually enough energy remaining to do the job. If it were me? I'd go with the Creedmoor. Personal choice, I hate trimming brass and the shoulder angle of the Creedmoor brass means less growth over the 260 Rem. From a semi-auto the "4 reloads and chuck it" school of thought has a lot of good history behind it. Jimro __________________ Machine guns are awesome until you have to carry one.

August 10, 2012, 12:39 AM	#20
Mr. Dusty Junior Member Join Date: December 24, 2011 Posts: 4	This does indeed look like one of those threads that just won't ever die LOL. I haven't posted on this particular forum as much as I'd like but I've seen plenty just like it everywhere else. It seems that the question is still quite relevant; in all honesty I can't really say I'd pick any of them just for the sake of doing so. I think a more relevant question would be which of the stated calibers is best for X purposes, it's pros and cons, and ultimately any other miscellaneous information. 6.5x284: I really like this cartridge due to how incredibly accurate it can be loaded as well as it's dominant power over the rest of the aforementioned 6.5's. One thing to consider with this round though is it's OAL in the neighborhood of 82mm give or take. This means it's not going to fit into an AR-10 platform nor will it fit into an AR-15. You could possibly get it to work in a customized 84mm semi-automatic rifle but due to very mild taper (if any) and it's neck being more akin to a BR rifle than a tactical...feeding could be a problem. It absolutely dominates the rest in terms of power, it's accuracy holds legendary status in F-class shooting...but you're probably best off using this rifle in a bolt action rifle. 6.5 Grendel: I'll have to admit that I'm not a big fan of this particular incarnation of the .264, but it does seem to have found itself a loyal following; particularly if you like Ar-15s or other rifles with the "super short" chamber. It's power is considerably far behind the rest of the pack...but if it's anything like the 6.5x55mm or 6.5 Arisaka rounds in the same league, I'd imagine it's probably quieter. I could also imagine there are times where you might want more mild velocities for hunting purposes so you can eat up to the hole, reduced velocities to a point can actually improve penetration. Overall this is the round you'd want for an AR-15 platform or similar light weaponry. It's got the least recoil of the others and can still be used on larger game due to the 6.5mm's density and consistency. 260 Rem: This one is probably truly smack dab in the middle. The .308 parent case makes brass almost impossible to run out of. It may be a pain to form your own brass from .308 or .243, but all in all having a cartridge that can utilize so many types of extremely common brass is an advantage that should -never- be taken lightly. It's rim and shape make it superb for an Ar-10 project, or any short length rifle for that matter. Heck, the Remington 74XX series made .260's, as did the 7600 pump if I recall correctly. This is the round you'll want if you're looking for a multi-purpose 6.5mm. it's capable of target shooting, it's capable of hunting with, shtf/zombies, and the amount of rifles you could customize into this caliber is nothing short of inspiring. 6.5x47mm Lapua: Now I have to admit that I have no experience with this particular round...but it's design seems to be aimed at a very specific purpose. Unlike the .260 Rem the case is supposedly a bit more efficient, but what is certain is that it's shorter brass allows it to seat bullets with large, competition style BC slugs while still fitting in a magazine. It's design purportedly reduces barrel wear, and even though it was designed for competitions it's tactical advantages really make it shine in terms of the rounds capable of competing. This is the type of round you'd want if you're specifically looking for a highly accurate tactical rifle, or a round that won't burn up match barrels like the short and fat PPC/BR type rounds. 6.5 Creedmoor: Honestly I don't see enough evidence that would suggest this cartridge is anything other than another option for match or tactical/hunting situations. It's not bad but it doesn't seem to do anything significant enough to be touted over the former two rounds. It's another round you can easily swap into an AR-10/.308 length chamber easily. The Lapua is slightly less powerful than the .260 and Creedmoor, and perhaps more expensive. The .260 uses common brass that some would say is inferior to the Creedmoor's design, and the Creedmoor has -slightly- more room for a longer/bigger slug. So, all in all, This round is what you'd want if you aren't impressed with the .260 or the 6.5x47mm, or just want to have something more unique than a necked down .308. I hope I haven't been too entirely rambly (though I'm sure I have), as well as hope I've helped those who might still be wondering which they want, if any of them are better or worse for X or Y situations, so forth so on. Also; do remember that the 6.5x55mm is still a very viable choice that exceeds the power of the .260. For those who like old military rifles (especially modified) the 6.5x50mm Arisaka's power is on par with the 6.5mm Grendel.