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 AR-15 variant with the greatest energy at 100 meters?
Grimjaw5  [Team Member]
8/15/2010 5:20:06 AM EST
Yeah yeah, I know....

I was looking at the big bore AR-15 variants and it started me thinking. Which of the more common AR-15 variants has te most energy at 100 meters? IS it one of the heavy, but slow moving big bores or one of the light weights moving at a fraction of lightspeed or something in the middle?
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Altair  [Team Member]
8/15/2010 7:15:06 AM EST
Here is some data from a few of the rounds I've looked at. All from 20" barrels except the .358, which was an 18.5". This is just data I've come across in manuals or on the web so it is just a rough idea. For example the Grendel data came from 65grendel.com and the 6.8 data came from 68forums.com. I picked the load from my lists that had the highest energy at 100 yards. My ballistic program does yards, not meters, so I gave numbers for 100 yards. Well that, and we are in the US...


.223 68gr BTHP with 2700fps MV has 900 ft-lbs at 100 yards
6x45 90gr BTBT with 2500fps MV has 1019 ft-lbs at 100 yards
.25-223 100gr SPBT with 2600fps MV has 1240 ft-lbs at 100 yards
6.5MPC 108gr Scenar with 2650fps MV has 1450 ft-lbs at 100 yards
6.5 Grendel 123gr A-Max with 2550fps MV has 1539 ft-lbs at 100 yards
6.8 SPC 110gr BTBT with 2700fps MV has 1469 ft-lbs at 100 yards
7.62x40 125gr BTBT with 2600fps MV has 1538 ft-lbs at 100 yards
.358 Gremlin 180gr SP with 2300fps MV has 1541 ft-lbs at 100 yards
Powder_Burns  [Member]
8/15/2010 7:36:52 AM EST
A 325gr Flext tip from a .458 Socom at 1800fps MV has 1657ftlbs of energy at 100yd. Thats the only example I have handy. (16" barrel)
A 130gr Speer SPBT from a 6.8 SPC at 2500fps MV has 1659ftlbs of energy at 100yd. (16" barrel)
ILove2Shoot  [Industry Partner]
8/15/2010 12:19:35 PM EST
wow, no one has posted the Wulf yet.....

50 Beowulf.........From Alex Arms website from a 16" barrel (since that is what I have):
334 grn FMJ. Velocity at 100yard is 1570FPS Energy is 1828 ft lbs.

I qoute that one since my two pet loads use Rainer 335 grn FP and 335grn HP....and having just Chrono'd the FP this weekend, I am just a hair under 1900FPS, but they were load a couple tenths of a grain on the light side.

I have 400 grain and 500 grain projectiles I need to work loads up for, but figure the 400s should be around 1900 to 1950Ft lbs of energy at 100 yards..........the 500grn projectiles will be a hair higher..........

hi-tech-rancher  [Team Member]
8/15/2010 12:40:57 PM EST
- 6.8 X 43

- .458 SOCOM,

- .50 Beo

This is the list in terms of the easiest to acquire (AKA "more common" ), with factory ammo available.

when you look at all the above lists, the 6.8 SPC and 6.5 Grendel hang with some pretty impressive company


ETA: though not necessarily "more common," when you look at some of the testing Bill Wilson did with the .30 RAR, it should also be listed.
Krochus  [Member]
8/15/2010 1:13:44 PM EST
By the numbers a 110g 25wssm bullet packs 2007ft lbs at 100yds
Singlestack_Wonder  [Team Member]
8/15/2010 2:52:56 PM EST
7.62x51, 147FMJ. 1925ft/lbs at 100 yards.
Grimjaw5  [Team Member]
8/15/2010 3:28:00 PM EST
Originally Posted By Singlestack_Wonder:
7.62x51, 147FMJ. 1925ft/lbs at 100 yards.


That is a little hard to fit in an AR-15. AR-10 is a completely different animal.
320pf  [Member]
8/15/2010 3:44:08 PM EST
I would consider the AR10 a AR15 variant. If you want to only consider the small frame AR15 then the 7.62x51 is off the table.

320pf
320pf  [Member]
8/15/2010 4:26:46 PM EST
".223 68gr BTHP with 2700fps MV has 900 ft-lbs at 100 yards
6x45 90gr BTBT with 2500fps MV has 1019 ft-lbs at 100 yards
"

.25-223 100gr SPBT with 2550-2600fps MV has 1240 ft-lbs at 100 yards (16-inch barrel)
.25-223 100gr SPBT with ~2675fps MV has ~1320 ft-lbs at 100 yards (20-inch barrel)
300-221 Fireball (300 Whisper) 125gr Nos BT 2300fps MV has 1240 ft-lbs at 100 yards (20-inch barrel)


"6.5MPC 108gr Scenar with 2650fps MV has 1450 ft-lbs at 100 yards
6.5 Grendel 123gr A-Max with 2550fps MV has 1539 ft-lbs at 100 yards
6.8 SPC 110gr BTBT with 2700fps MV has 1469 ft-lbs at 100 yards
7.62x40 125gr BTBT with 2600fps MV has 1538 ft-lbs at 100 yards
.358 Gremlin 180gr SP with 2300fps MV has 1541 ft-lbs at 100 yards
"

In the 25-223, a 16-inch barrel will give you 2550 to 2600 fps. This equates to about 1450-1500 ft-lbs at the muzzle which ends up being about 1220-1240 at 100 yards. If you step up to a 20-inch barrel you will pick up an additional 75-80 fps (2640 to 2680 fps), which gives you around 1550 to 1580 ft-lbs at the muzzle. At 100 yards is drops down to 1300-1340 ft-lbs.

You can also add the 300-221 Fireball to this list. From.25-223 100gr SPBT with 2600fps MV has 1240 ft-lbs at 100 yards a 16 inch barrel, the 300-221 Fireball can drive 125 g Nosler Ballistic Tip to about 2240 fps (about a 1380 ft-lbs energy at the muzzle and 1140 at 100 yrds). In a 20 inch barrel you will only pick up and additional 50 fps and an additional 100 ft-lbs at the muzzle. This equates to about 1220 ft-lbs at 100 yrds.

Basically, what all this works out to is that the bigger the diameter of the bullet, the more energy that can be transfered from the burning powder to the bullet.

I hope this helps

320pf

P.S.
Someone should add data for the 7.62x39.
Gunwritr  [Team Member]
8/15/2010 5:17:54 PM EST
If we are just talking ft-lbs

driving a 144 grain Lapua FMJ at 2,450 fps the 6.5mm Grendel will churn out 1,716 fps at 100 yards.....
it will retain 966 ft-lbs at 500 yards....
jestertoo  [Team Member]
8/16/2010 10:21:50 AM EST
What about the WSSMs?
bowslngr  [Team Member]
8/16/2010 10:59:53 AM EST
Originally Posted By jestertoo:
What about the WSSMs?


25 WSSM was referenced above.

Here is the winner:

300 OSSM pushing a 150 grain SGK at over 3000 fps. At 100 yds the energy would be 2572
MartytW  [Team Member]
8/16/2010 4:13:29 PM EST
Originally Posted By bowslngr:
Originally Posted By jestertoo:
What about the WSSMs?


25 WSSM was referenced above.

Here is the winner:

300 OSSM pushing a 150 grain SGK at over 3000 fps. At 100 yds the energy would is 2572


Nah....

500 Phantom using Oly Arms components, 16" barreled AR15 upper.
Woodleigh 440 gr bullet at 2000 fps MV still holds over 3000 ft-lb at 100 meters... at 100 yards, it holds close to 3100 fpe...
This load fits in the AR15 magazine...
bowslngr  [Team Member]
8/17/2010 1:28:06 AM EST
Originally Posted By MartytW:
Originally Posted By bowslngr:
Originally Posted By jestertoo:
What about the WSSMs?


25 WSSM was referenced above.

Here is the winner:

300 OSSM pushing a 150 grain SGK at over 3000 fps. At 100 yds the energy would is 2572


Nah....

500 Phantom using Oly Arms components, 16" barreled AR15 upper.
Woodleigh 440 gr bullet at 2000 fps MV still holds over 3000 ft-lb at 100 meters... at 100 yards, it holds close to 3100 fpe...

...


Sure enough. Is anyone making these in the AR-15 platform? Where would you get the Oly components? –– they do not sell their WSSM components separately. Would have to buy a complete upper and take the barrel off it I guess. Then what do you do with the barrel? Nobody can use it for a build because Oly doesn't sell components. Interesting concept though. Perhaps Dtech would make them.
This load fits in the AR15 magazine

Forest  [Moderator]
8/17/2010 6:45:32 AM EST
Another consideration is what barrel length?

Are you looking for max 'energy' from a particular barrel length?

How about uppers or feeding? If it's open ended then the .50 BMG wins, and there was a magazine fed .50BMG upper for the AR-15 (bolt action, fed from the side).
Afterwork_Ninja  [Team Member]
8/17/2010 6:51:14 AM EST
Originally Posted By Forest:
Another consideration is what barrel length?

Are you looking for max 'energy' from a particular barrel length?

How about uppers or feeding? If it's open ended then the .50 BMG wins, and there was a magazine fed .50BMG upper for the AR-15 (bolt action, fed from the side).


Who makes that? Got a link?
Forest  [Moderator]
8/17/2010 7:13:50 AM EST
Here is 'the original' designed by Mark Serbu: http://mmag.biz/

Here is another: http://www.tactilite.com/models/view-all-products.html

And yet another: http://www.ultramag50.com/

In case you missed the above here another one: http://www.safetyharborfirearms.com/Products/Upper_Conversions/upper_conversions.html
MartytW  [Team Member]
8/17/2010 6:15:13 PM EST
Originally Posted By bowslngr:
Originally Posted By MartytW:
Originally Posted By bowslngr:
Originally Posted By jestertoo:
What about the WSSMs?


25 WSSM was referenced above.

Here is the winner:

300 OSSM pushing a 150 grain SGK at over 3000 fps. At 100 yds the energy would is 2572


Nah....

500 Phantom using Oly Arms components, 16" barreled AR15 upper.
Woodleigh 440 gr bullet at 2000 fps MV still holds over 3000 ft-lb at 100 meters... at 100 yards, it holds close to 3100 fpe...

...


Sure enough. Is anyone making these in the AR-15 platform? Where would you get the Oly components? –– they do not sell their WSSM components separately. Would have to buy a complete upper and take the barrel off it I guess. Then what do you do with the barrel? Nobody can use it for a build because Oly doesn't sell components. Interesting concept though. Perhaps Dtech would make them.
This load fits in the AR15 magazine



We made four of them, took apart 243 WSSM uppers. The 243 barrels were recycled into 6 x 45 barrels and put to good use, very simply to do...
The load fits the AR15 magazine just fine, but the feedlips have to opened up to let the mag release the large round.
This is one of the "Fab Four"


Another one of the Fab Four


Two of the Fab Four before test firing


Loaded round in the mag


We stopped building these due to lack of brass
bowslngr  [Team Member]
8/18/2010 12:41:56 AM EST
MartyW,
Very interesting stuff. I would guess the bullet selection would be very limited as well.
eightshot627  [Member]
8/18/2010 3:21:26 AM EST
I didn’t see the 450 in the list and wondered how it stacked up:

450 Bushmaster Rem 250 gr Core-Lokt
Muzzle 2200fps/2686ft-lbs 100yds 1831 fps /1860 ft-lbss

450 Bushmaster Hornady 250 gr FTX® LEVERevolution®
Muzzle 2200fps/2686ft-lbs 100yds 1840 fps /1879 ft-lbss

From the Remington and Hornady site.

I don’t have the program or math skills to convert to 100 Meters

Walt
RuLins05  [Member]
8/18/2010 7:19:21 AM EST
Originally Posted By eightshot627:
I didn’t see the 450 in the list and wondered how it stacked up:

450 Bushmaster Rem 250 gr Core-Lokt
Muzzle 2200fps/2686ft-lbs 100yds 1831 fps /1860 ft-lbss

450 Bushmaster Hornady 250 gr FTX® LEVERevolution®
Muzzle 2200fps/2686ft-lbs 100yds 1840 fps /1879 ft-lbss

From the Remington and Hornady site.

I don’t have the program or math skills to convert to 100 Meters

Walt


As far as availability is concerned, I think the 450B is a good candidate. Don't get me wrong there are more powerful loads out there but I like being able to go buy ammo if the need arises and the Cabela's near me (30min or so) has always had ammo in stock when I get up there.
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