So I went out on a limb yesterday and bought 250 rds of Wolf 62gr HP. I had never shot any and figured for the money, I'd try it for plinking.  

Now to see if my AR's would digest it. I loaded 5rds ea in 5 mags and proceded to try each of my rifles. I'll only mention each upper as the lowers don't really matter for this test.

1) CMP 5.56 NATO 1/7 20" govt
2) CMP 5.56 NATO 1/7 20" govt
3) EMP 5.56 NATO 1/7 20" govt
4) FNMI MP 5.56 NATO 1/7 20" govt
5) CMMG MP 5.56 NATO 1/7 16" govt M4

All chrome lined bore and chamber.

Anyway, they all did fine, no hiccups except for the FN barrel. I was pissed and couldn't figure it out. I loaded 5 rds of LC 62gr  M855 and it shot those fine. With the Wolf it was a single shot. Well, I just figured it out today.

I took the barrel off so I could mate it with an FN marked upper I just got from a board member, (Thanks machinehead!) and I took another look at the bolt (MPC). Two of the gas rings were missing about 1/16 of their length. I replaced them with two new ones I had stashed and BAM, BAM, BAM! Good to go!

Just remember to check everything when you have malfuntions like that. I did check the gas key first and finding it tight didn't go any further yesterday, but it was those tiny gas rings. Whodathunkit?

I could tell a big difference in recoil though. The Wolf isn't loaded nearly as hot as the Lake City. Anyone know the difference in muzzle veloicity?

AIRBORNE!

thanks for teh props.  ive got my stock on but havent shot anything yet .  glad your happy with the upper.  

Quoted: I took the barrel off so I could mate it with an FN marked upper I just got from a board member, (Thanks machinehead!) and I took another look at the bolt (MPC). Two of the gas rings were missing about 1/16 of their length. I replaced them with two new ones I had stashed and BAM, BAM, BAM! Good to go! hr

I use RRA gapless rings in all of my personal builds to avoid this problem.  All of our RRA bolt carrier assemblies come with them standard too.

Brett

Quoted: Quoted: I took the barrel off so I could mate it with an FN marked upper I just got from a board member, (Thanks machinehead!) and I took another look at the bolt (MPC). Two of the gas rings were missing about 1/16 of their length. I replaced them with two new ones I had stashed and BAM, BAM, BAM! Good to go! I use RRA gapless rings in all of my personal builds to avoid this problem.  All of our RRA bolt carrier assemblies come with them standard too. Brett

Do you get these straight from RRA, or do you have another source?  Just curious.  I am attempting to start a spare parts "stash" of sorts.  

Quoted: I could tell a big difference in recoil though. The Wolf isn't loaded nearly as hot as the Lake City. Anyone know the difference in muzzle veloicity? AIRBORNE!

Assuming 62gr Wolf to 62gr XM855ish, you're talking about 200 fps difference (2900 vs. 3100).

Quoted: Quoted: Quoted: I took the barrel off so I could mate it with an FN marked upper I just got from a board member, (Thanks machinehead!) and I took another look at the bolt (MPC). Two of the gas rings were missing about 1/16 of their length. I replaced them with two new ones I had stashed and BAM, BAM, BAM! Good to go! hr I use RRA gapless rings in all of my personal builds to avoid this problem.  All of our RRA bolt carrier assemblies come with them standard too. Brett Do you get these straight from RRA, or do you have another source?  Just curious.  I am attempting to start a spare parts "stash" of sorts.

PK Firearms

Brett

What prevents these RRA rings from aligning?

Thanks for the info.

I've always used the standard rings without a problem, but have wondered about upgrading to a Macfarland ring to prevent possible alignment of the gas rings.  The reason I haven't is because I've heard from some users that they cause the bolt to fit very tightly within the carrier.

Is this an issue with the RRA gapless rings?

In a properly functioning AR aligned gas rings will not cause any problems.

If the gas rings being aligned caused a short stroking problem, the gas delivery was marginal to begin with.

Quoted: In a properly functioning AR aligned gas rings will not cause any problems. If the gas rings being aligned caused a short stroking problem, the gas delivery was marginal to begin with.

+1 This has been my experience also.

funny how in spec ammo still ran fine with the 2 broken gas rings.

COMMENCE PANIC BUYING OF RRA RING THINGS!!!!

I'll Stick w/ USGI rings.