Barnes 120g mb and ar comp

[sbowhuntr]

Anyone try ar comp with the barnes 120g match burner? I see a load in bft's list..
120 A-Max / 28.0 AR-Comp / R7.5 / 22bbl / 2580 fps (Lane Pearce, ShootingTimes.com, 20140311)
Would this be a max charge @28.0g??
A starting point would be great if you guys might know this info.

[BowChamp]

27.6gr AR-Comp with 120gr/123gr bullets works very well in my rifles. AR-Comp is my favorite powder so far.

I've been as high as 28.2...not as smooth on the cycle and hard on my brass.

[Cal]

Hey Sbowhuntr,

"Bear in mind that almost all of these loads — unless you see a work-up progression shown — are what the reloader considered max in his gun. He stopped for a reason. Think about this. So start 3 grains of powder lower than the loads listed here and carefully work up using standard safe reloading procedures."

Hope this helps.

[myrifle]

Hey Sbowhuntr,

"Bear in mind that almost all of these loads — unless you see a work-up progression shown — are what the reloader considered max in his gun. He stopped for a reason. Think about this. So start 3 grains of powder lower than the loads listed here and carefully work up using standard safe reloading procedures."

Hope this helps.

If I started that low from some of the loads listed here, my gun wouldnt even cycle.

I used up some arcomp with several 120 grain hpbt bullets and always ended up in the 28 to 28.4 grain range. For a safe load that gave great sd/es numbers and adequate to great groups while providing a proper cycling gun.

[Cal]

Myrifle,
Sounds good, I too looked at the loads on BFT's list.
The caution, IMO, is justified. Each rifle is different and has the potential for a spectacular failure.
I was just trying to help someone find a starting point.

[Bobke]

I’d suggest working up from 26.0gr in .2gr increments. I’ve settled at 27.2-27.4 of ARC, depending on shape of bullets in question, for 2500-2525fps and low ES/SD in multiple 20” barrels. Really not sure how anyone is pouring 28+gr and not experiencing serious powder compression in Hornady or Lapua brass. Another upside is brass life and excellent accuracy. Don’t be foolish enough to head straight for the 28gr loads without understanding the risk in doing so.

[sbowhuntr]

I’d suggest working up from 26.0gr in .2gr increments. I’ve settled at 27.2-27.4 of ARC, depending on shape of bullets in question, for 2500-2525fps and low ES/SD in multiple 20” barrels. Really not sure how anyone is pouring 28+gr and not experiencing serious powder compression in Hornady or Lapua brass. Another upside is brass life and excellent accuracy. Don’t be foolish enough to head straight for the 28gr loads without understanding the risk in doing so.

Bobke, I was going to start around 26.3 and work up from there, not alot of info on arc so I figured the hoard was the place to ask.
As for primers are the cci 450's the norm? I have been exclusively using these but I have rem 7 1/2, fed 205m and cci br4. I am giving cfe223 a try also as I have a few pounds on hand. Thanks guys for all the suggestions!

[LRRPF52]

Be careful when working up a load with AR Comp under anything 120gr and higher cup and core.

You’ll start to reach the top in the mid 27.x grain charge weight. Some rifles and chambers might handle up to 28.0gr ok with a more conventional 120-123gr cup and core bullet like an SST, A-MAX, ELD-M, or Nosler Ballistic Tip, but under harder/thicker jacketed bullets, it will hit maximum peak pressure sooner.

In the Grendel Handbooks, there is data with it under several 120-123gr bullets.

I would do a ladder starting with 26.0gr under the 120gr Match Burner in single strings of increasing charge weight by no more than .3gr over a chronograph and see what it shows you.

That’s assuming using one of the common cases, whether they be Lapua, Hornady, Norma, or Starline.

I would not load past 28.0gr. AR-Comp has a similar density and burn rate to 8208 XBR, so both are slightly on the fast side for bullets over 107gr.

[myrifle]

Be careful when working up a load with AR Comp under anything 120gr and higher cup and core.

You’ll start to reach the top in the mid 27.x grain charge weight. Some rifles and chambers might handle up to 28.0gr ok with a more conventional 120-123gr cup and core bullet like an SST, A-MAX, ELD-M, or Nosler Ballistic Tip, but under harder/thicker jacketed bullets, it will hit maximum peak pressure sooner.

In the Grendel Handbooks, there is data with it under several 120-123gr bullets.

I would do a ladder starting with 26.0gr under the 120gr Match Burner in single strings of increasing charge weight by no more than .3gr over a chronograph and see what it shows you.

That’s assuming using one of the common cases, whether they be Lapua, Hornady, Norma, or Starline.

I would not load past 28.0gr. AR-Comp has a similar density and burn rate to 8208 XBR, so both are slightly on the fast side for bullets over 107gr.

Not trying to be argumentative.

But having used both powders. Arcomp acts nothing like 8208 at or in the 28 to 28.6 grain range.

It has been remarkably stable and well mannered at those charge weights. That has been my experience with well over 14 grendels now with 120 gold dots, 123 eld-m's.

Only use hornady and starline cases in my ar grendels, and haven't had a compressed load yet. Well let me say i cant hear are feel any powder compression and my micro seating die isnt showing any signs that I'm compressing powder as well.