Tackdriving AR10 Load at Max.

[Ishallbie O'Cullkillin]

Ok, Ok, It's only 1/2 MOA, but this is my AR10A4 with stock chrome lined 20" barrel, free floated. 45gr Varget, 168 Amax, Fed brass, WLR primer, oal 2.81" @ 2610fps. I am waiting for the 90F weather to test for excessive pressure, but want to know if this load is going to beat my rifle up prematurely. Mild primer flattening, & a shiny ejector mark seem to be the only pressure signs. This rifle usually prints around MOA with pet load of 43.5gr H4895 & 168 Amax, Win Brass, CCI br primer. Opinions?

 

[Falar]

Re: Tackdriving AR10 Load at Max.

Got any pics? On my AR10 the ejector marks are the first pressure sign, I can get deep ones before the primers start looking scary.

 

[Ishallbie O'Cullkillin]

Re: Tackdriving AR10 Load at Max.

No pics right now. I will on the next test run.I am trying to get away from the max loads because I don't want to stretch the primer pockets to bad on this Fed brass, but the load rocks.

 

[esorensen]

Re: Tackdriving AR10 Load at Max.

I doubt you will find much difference at 90F or even 100F for that matter with Varget. Try 45.5 with the CCI BR2 or FGMM 210M. I use Win brass. It is harder than Federal. It seems to me A LOT of AR10's leave ejector marks even with mild loads. I was popping primers out of FGMM factory ammo and the brass is toast.

 

[Downzero]

Re: Tackdriving AR10 Load at Max.

That's a pretty common load. I really don't think you'll have any problems.

I get mild ejector wipes on my AR brass long before I hit unsafe pressures. I'd run it.

 

[sniper7mm]

Re: Tackdriving AR10 Load at Max.

I shot a bunch of FGMM 168's out of my DPMS LR308 this past weekend. The brass was toast. I would have to file the ejector marks down just to reload! I guess the Federal brass is just that soft.

 

[Ishallbie O'Cullkillin]

Re: Tackdriving AR10 Load at Max.

My primary concern is the rifle. I have about 500 pcs of Win brass, once fired. About a year ago I stumbled on a honey hole of once fired Fed brass straight from the LE range, about 3100 pcs. My AR10 doesn't hurt the brass too bad, & when primer pockets get stretched, I have 5000 Wolf LR primers on standby. I have been handloading for 8 years & just recently lost some primers for the first time on a .223 load.
Thanks for the replies!

 

[Falar]

Re: Tackdriving AR10 Load at Max.

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Downzero</div><div class="ubbcode-body">That's a pretty common load. I really don't think you'll have any problems.

I get mild ejector wipes on my AR brass long before I hit unsafe pressures. I'd run it. </div></div>

This seems to be true for me as well. I've heard that it is common on AR10s from guys who have been loading for it longer than I have.

 

[Queequeg]

Re: Tackdriving AR10 Load at Max.

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: AlcoholicusRex</div><div class="ubbcode-body"> Ok, Ok, It's only 1/2 MOA, but this is my AR10A4 with stock chrome lined 20" barrel, free floated. 45gr Varget, 168 Amax, Fed brass, WLP primer, oal 2.81" @ 2610fps. I am waiting for the 90F weather to test for excessive pressure, but want to know if this load is going to beat my rifle up prematurely. Mild primer flattening, & a shiny ejector mark seem to be the only pressure signs. This rifle usually prints around MOA with pet load of 43.5gr H4895 & 168 Amax, Win Brass, CCI br primer. Opinions? </div></div>

How did you achieve your free floating floating barrel? I have this rifle as well though with the collapsible stock. I'm not getting that kind of accuracy but then I haven't expected to find it; self fulfilling prophecy perhaps?

You meant WL<span style="text-decoration: underline">R</span> primers right?

Looks like you have found the magic!

 

[Ishallbie O'Cullkillin]

Re: Tackdriving AR10 Load at Max.

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: queequeg</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: AlcoholicusRex</div><div class="ubbcode-body"> Ok, Ok, It's only 1/2 MOA, but this is my AR10A4 with stock chrome lined 20" barrel, free floated. 45gr Varget, 168 Amax, Fed brass, WLP primer, oal 2.81" @ 2610fps. I am waiting for the 90F weather to test for excessive pressure, but want to know if this load is going to beat my rifle up prematurely. Mild primer flattening, & a shiny ejector mark seem to be the only pressure signs. This rifle usually prints around MOA with pet load of 43.5gr H4895 & 168 Amax, Win Brass, CCI br primer. Opinions? </div></div>

How did you achieve your free floating floating barrel? I have this rifle as well though with the collapsible stock. I'm not getting that kind of accuracy but then I haven't expected to find it; self fulfilling prophecy perhaps?

You meant WL<span style="text-decoration: underline">R</span> primers right?

Looks like you have found the magic! </div></div> I removed the stock hand guard & barrel nut and replaced it with a PRI carbon fiber hand guard which threads on to the upper receiver & does not touch the barrel. This rifle has about 800 rds thru it, most of them in load testing. It has the older 1/10 twist medium wt. chrome lined barrels, which is fat under the hand guards. I ran some Tubb's final finish abrasive bullets thru about 200rds ago, don't know if that helped or not, JP trigger. WLR primers.

 

[Ishallbie O'Cullkillin]

Re: Tackdriving AR10 Load at Max.


Ok. I think I jumped the gun a little. Another 20rds of 45gr Varget 168gr Amax yesterday, and all 5 shot groups were averaging 1.5 MOA.Too much coffee maybe.

 

[bigwheeler]

Re: Tackdriving AR10 Load at Max.

Bolt swipe and ejector marks are a sign of an over pressured gas system and bolt timing not a high pressure load as far as chamber pressure. Try a heavier buffer and you may cure all your brass damage problems. FGMM runs fine in my 10t with no brass damage and it is a bone stock gun.

 

[Joeyhotfizzle]

Re: Tackdriving AR10 Load at Max.

Man these AR10's are hard to load for. I cannot make my AR 10T to shoot under 1 moa (but then again this was the first 60 rounds through the rifle). Now I'm wondering maybe I should have bought a DPMS 308

. Haha! Hopefully I'll get better, goodluck with yours.

Joseph