Basically wanted to see how reliable this ammo was and the effect on the brass and really overall how it performed. I do not personally own a chrono, but I was informed by someone with a similar set up (18" barrel) that the round is moving at 2854 on average. Not bad since the fps listed on the box is 3000. anyway, here's my functionality results.

This is my rifle. CMMG MK-3 .308 w/ 18" stainless barrel, SJC Titan muzzle brake, LaRue SPR-E with Nikon Monarch 4-16x42 SF MIldot, LaRue QD Harris Bipod


Went out and sighted in with / tested out the Hornady 150gr SST Superformance. I went ahead and went with the 150gr SST for hunting mule deer at 200+ yards this coming week. The ammo functioned flawlessly, and the brass was not destroyed or overly mangled as previously experienced by other members. They were not bent, and the only real markings were small abrasions or dimples rather on the neck as you can see in the pictures below. Sighted in at 50 yards for a 200 yard zero.







The bullets were fragmented as expected at 50 yards through cardboard and some fence pickets, although I was able to recover all 6 rounds fired more or less.

how was the accuracy?

At 50 yards it was pretty much one hole. The rifle and ammo did it's part and if I had done mine it would have been one hole.

I shoot Hornady Superperformance 165 gr SST's out of my .308 (18" barrel), and I have had no issues either.

I have an adjustable gas block, and even on the highest setting, I see no issues.  I am able to turn the gas down quite a bit and still get it to function flawlessly.

If you go to Hornady's website, they state that Superperformance ammo is safe to run in semi-auto's, they just add the caveat that an adjustable gas block might be beneficial.

I get great accuracy out of this stuff.  I run it exclusively.

OP, can you measure your firing pin hole diameter on the bolt face please?  That is excellent news.

I would prefer the 150gr GMX load for mulies, but a solid vital zone hit with the SST outside of a certain distance will result in a good kill most often.  With the fast speed inside of the fragmentation threshold of that bullet, I would probably lean on a neck or head shot, with a solid zero on the stick.

Hornady does show a barely ideal gas system signature for the MLGS on their site, and it looks like that is working out for you.  What was the temperature by the way?

I would run your ballistics based on a 2800fps mv, .415 G1 BC for the 150gr SST, and punch in your optic height above bore.  Zero at 200yds if you can, and make confident hits with a center hold out to around 225yds.

This is great news for you and your blaster.  I wonder if they have reformulated, understanding that there is a growing trend of .308 gas guns.

Have the same exact rifle.

Gas key wasn't staked from the factory.

Accurate as hell.

Have a 24" DPMS upper incoming for it.

My R25 eats them with no issue.  About 1.25 MOA