AR15.Com Archives
 Feet per second
AmericalJoe  [Member]
2/26/2009 11:00:23 PM
I'm trying to work up a good load for my Stag AR 16' barrel with 1/9 twist. I get good accuracy with a couple of different loads. I'm using Hornady 55 gr fmjbt w/c, winchester brass, cci 450 primers with H-335 powder. I get good accuracy at 22.5, 24 and 25 grains of powder. I get a range from 2560 to 2875 FPS . What kind of FPS should I be looking for? I want these loads just for the range. What kind of FPS are you guys shooting?
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Uni-Vibe  [Member]
2/26/2009 11:07:51 PM
Milspec 55 grain loads out of a 20" go 3250. Subtract about 150 for a sixteen incher.

My pet load goes 140 fps slower than milspec.

Your loads sound pretty slow.
AME  [Member]
2/26/2009 11:19:16 PM
For me at the range I dont care what FPS I get as
long as the groups are good
My 1-9 likes
24.2gr Varget
69gr Sierra MK
CCI 450
COL 2.265
dryflash3  [Team Member]
2/27/2009 12:10:05 AM
Use the load that shoots best (most accurate) in your rifle.

Next question.
SMJayman  [Member]
2/27/2009 10:53:55 AM
M193 comes out of my 16" AR at around 3100 fps, all day long. I have never been able to duplicate that velocity with a listed load. For the record, your 2875fps with the 25.0gr of H335 sounds about right to me, and is right where I end up with a near max loading of BL-C(2) under a similar projectile.

So, bottom line, your velocities are fine, pick the load that gives you the best accuracy and runs the gun the way you want it to run. :)
popnfresh  [Member]
2/27/2009 12:10:18 PM
I run mine as slow as possible while still being reliable in my 7" and decent groups to 50 yards. My pistol runs about 1900-2000fps and my 16" runs at 2600-2700fps with 55gr fmjs. I see no need in hammering the gun and working the brass and wasting powder with high pressure loads just to poke holes at the range.

FriscoPete  [Member]
2/27/2009 12:45:01 PM
FPS depends on what you want as the end user - limited by the pressure limitation of the cartridge and rifle. I know that H-335 is cleaner when fired in its designed pressure range, and it was designed as a military powder, so you don't want to get too low or that aspect suffers. Certainly the design intent of the .223/5.56 cartridge was velocity-oriented for military and varmint use.

Some people, usually target shooters, only look at what gives the best 100 yard groups, which isn't necessarily velocity related, although Conventional Wisdom seems to think it is (and that less is better..?) This is basically where you are at it seems to me, and therefore you should go with what gives you the accuracy you want to punch paper and if there is a toss-up between two loads of different velocities, the higher will give less wind drift.

Others want the flatter trajectory that higher velocity gives them so that range estimation on unknown yardage targets is more forgiving and has less hold-over. The higher velocity also helps combat wind drift better, which is an unforeseen accuracy factor.
Hunters sometimes require top velocity for maximum ft/lbs of energy delivered on target when hunting coyotes etc.
And some who are interested in self-defense want maximum velocity because they realize that the killing effectiveness of the little FMJ M193 bullet is velocity dependent in order to get maximum fragmentation and also to extend the range at which that can occur. And because 16" barrels are slower than 20" barrels, some want all the velocity they can get safely from the short barrel.
So velocity can be important to some shooters.

You can chronograph factory ammo of the same bullet weight and see what velocity that gives, and use that as a benchmark.

FYI - Using 26.0 grains of H-335, a 55-gr Hornady bullet and similar components gave me 2922 fps from a 1-9" 16-inch NATO chambered AR. This would be a maximum working load and shoots 1/2 MOA from that particular rifle, although the load is intended to punch fur rather than paper.
The same load from my 20" 1-9" AR15 goes 3153 fps.
Black Hills factory 68-grain Match goes 2724 fps from the 16" barrel.


QuicksilverJPR  [Team Member]
2/27/2009 2:57:48 PM
Originally Posted By SMJayman:
M193 comes out of my 16" AR at around 3100 fps, all day long. I have never been able to duplicate that velocity with a listed load. For the record, your 2875fps with the 25.0gr of H335 sounds about right to me, and is right where I end up with a near max loading of BL-C(2) under a similar projectile.

So, bottom line, your velocities are fine, pick the load that gives you the best accuracy and runs the gun the way you want it to run. :)



27.5gr of BL-C(2) is the max load for 55gr SP, which gives me right at 3,020 or so FPS. It's a 2 MOA load in my old 1:9" RRA upper. The same 27.5gr or Varget got me like 30 more fps, but was no where near as accurate...

Have you tried any Ramshot powder? I have a sample I'm about to play with...


ETA - My loads are out of a 16" barrel as well. Forgot to mention that earlier.
AmericalJoe  [Member]
2/27/2009 7:55:11 PM
I want to thank all you guys for all the feedback. You guys gave a lot of good info. The only powder I have tried for the .223 is H-335. I'm not real experinced at reloading but with help I'm learning. Thanks again.
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