Alliant AR Comp
Its burn rate is ideal for .223/5.56 cartridge. 
Case near full
This is 25.3 grains of AR Comp
Nammo Brass
Federal Gold Medal AR Match primers used
Alliant AR Comp
This is an extruded stick powder.  It meters "OK".  This is a good powder for 5.56 because at near ~55-60k PSI range or so, you will "probably" be compressing powder substantially with almost any bullet weight and OAL (AR15 OAL which is under 2.260).   So it would be hard to make a mistake and do some sort of giant, huge pressure because you just can't get enough powder in the case.  For this reason, we find this powder to be friendly to newer reloaders.
This powder has near same burn rate as Accurate 2230, except you can fit WAY less of this into the case.  Way less.
We are now near convinced AR Comp is a great choice for 55 grain bullets.  Its practically IDEAL.  Higher than average velocity, good accuracy, case near full, stick powder low SD so its good for long range too.  If your into shooting up to 300 yards, and 55 grain bullets are what you typically use?  Check out AR COMP, its hard to beat.





So...what about AR Comp and what do some cases look like?
Right click picture.. "View background image" To see huge detail, blown up...
  • Nammo Brass Case capacity ~29.50 Grains
  • Federal Gold Medal AR Match Primer
  • Top 4 row:  Berger 55 Match 24.7, 24.9,25.1,25.3 is 4th from top
  • Bot 2 Row: Sierra BlitzKing 55 24.5, 25.0 is very bot.
  • 2.255 OAL

  • Nammo Brass Case capacity ~29.50 Grains
  • Federal Gold Medal AR Match Primer
  • Top row:  Hornady 75 BTHP 22.6, 22.8, 23 is 3rd from top.
  • Bot Row: Berger 77 OTM 21.6 grains
  • 2.255 OAL

  • Nammo Brass Case capacity ~29.50 Grains
  • Federal Gold Medal AR Match Primer
  • Left:  Berger 77 OTM 21.8 Grains
  • Right:  Berger 77 OTM 22 Grains
  • 2.255 OAL

Alliant AR COMP
Some of these loads are above any manufacturer data.  Load at your own risk.  What we load doesn't mean it will be safe for you. Do not load above recommended manufacturer book maximums.

We use WOA "Predator" 20" upper with 25x magnification Viper Gen II.    All shots were 50 yards.

AR Comp is about as good as it gets for 55 grain it looks like. That is some very good group sizes.
Check load data below to see 50 yards converted to MOA.

Why do we shoot at 50 yards now? Not 100?  A few main reasons, in order:
  • Its far more easier to line up our rig to hit the EXACT tiny dot, the size of a pins head at 50.  At 100 its much harder to lock firm on that tiny dot.  Our data over many years of 50 yard testing vs 100 yard testing tell us the MOA is measureablely smaller by a fraction at 50 yards than 100.  Precisely because you can hold a tighter spot at 50. We are using 25x Viper PST Gen II optic.  Very clear.
  • At the club we belong, the 50 yard lane is protected from wind much better than the 100 yard areas. 
Some of the loads we tried
Load at your own risk.  What we load doesn't mean it will be safe for you. Do not load above recommended manufacturer book maximums.

Since AR Comp is a stick powder, we knew we were going to get pretty low standard deviations, but 1.9 over 5 shots is pretty impressive.  As we can see, taking the time to measure inside of each case and making everything uniform helped lower average SD across all groups, and overall.