How fussy are the ar pattern 308 rifles to powders and bullet weights?

[neverhome_rph]

While the reloading manuals provide data for the .308 Win in bullet weights ranging from 100 to 200 gr 'pills', my experience with semi-auto mil-spec long arms, beginning back with the M1 Garands up thru the M1-As, is that the gas-chambering systems won't tolerate broad ranges. 

I haven't found much on reloading the AR pattern 308's.  I would expect these rifles will handle the standard military bullet weights of 150 and 168gr., but what about the heavier hunting bullets from 175gr up thru the 200gr?

Are there any sources and/or links on reloading these rifles?

neverhome_rph

"Never be afraid to try something new.  Amateurs built the Ark, but experts built the Titanic."

[draco41]

I recall reading somewhere, that when the military conducted trials for the M110 SASS, the specification was for the M118LR ammo to be used, and that ammo uses the 175gr Sierra HPBT bullet loaded at 2600fps.

[imschur]

I asked a good friend who spent a good portion of his life in the FAL business about this.

Load data is only specific for the M1A as too fast a burn rate can lead to a bent op-rod and the bolt roller being battered. This is a trait that was inherited from the Garand.

[bandit10-4]

First off, Welcome!  I have been loading quite abit for mine and it has been very easy to load for.  I havent pushed the limits or anything, but seeing fantastic accuracy and no pressure problems as of yet...  Please post your results as you go in the reloading section.  Thanks for joining!

[SWshooter]

I've been loading bullet weights in 150,165, 180 and 190 grs. I've only tried Varget and H-4895 for powders. I've used charges from starting loads to max loads and haven't had any functional problems at all. Even the different bullet weights seem to shoot to the same POI.

[Dusty44]

I took my LR-308 to the range for the first time a couple of days ago.  I started with 175 Sierra HPBT and moderate loads of Varget.  These were single loaded by tossing them into the space on top of the mag and releasing the bolt. The rifle did well,  groups impressed me for the first rounds fired from the gun.  Several casings did not manage to exit the action and others did get out but without any enthusiasm. 

Then I fired some cheap Russian "Brown Bear"  140 gr soft point mostly to check magazine function,  10 rounds at a time.  The punch of the Russian ammo was impressive and there was no problem at all with the bolt function and case ejection.  I was glad for the steel casings that I did not have to chase.  The Sierra POI was on centerline and a couple of inches high,  tight for my  hold on the rifle.  The "Brown Bear"  POI for two successive 10 round clips with a cleaning between was higher,  well to the left (without changing the scope settings,  in the white of the paper on the upper left).  All 20 rounds held the same general POI and nearly 6 inch pattern,  100 yards.

I think the result shows a preference in my gun for the slightly heavier bullets and a need to find a powder that works better in this action.

Afterward,  I tried some "Brown Bear" in both of my bolt 308's and got matching perfect tight patterns on centerline and 2 inches high at 100 yards.