Headed to the gravel pit with a few magazines loaded with the newer Wolf 62gr FMJ.  My rifle would not fire five rounds without jamming.  The empty shell is ejected, but the next round up has the nose up on the ramp with the bolt half way closed on top of the round.  Does this sound like short stroking?  

I thought it was the new SA-80 magazine I was using, but a switch to a tried and true USGI did the same.  Unfortunately I didn't bring any more ammo with me to rule out the ammo, but it had shot flawlessly a week ago with my handloads.  This rifle has always shot the older Wolf (red sealant) without any problems, but this was the first time I've tried the new stuff.  

My troubleshooting found that the gas tube seems to be open and the carrier key tight, but I did find the gas rings on the bolt to be aligned.  I staggered them around, but won't have a chance to try this fix until next week.  Is this really that critical, or could it be that the combination of ring alignment and underloaded ammo is at fault?

Thanks

Hoppy

If the gas rings were alinged you could get short stroking with any ammo.  Now that you've staggered them give it another try.

I concur, it was most likely the aligned rings. I have chrono'ed both Wolf and Barnaul, and they are as "hot" as the Winchester and UMC Walmart rounds. You'll get about 3000fps with the 55gr stuff out of a 20" barrel, and slightly less with the 62gr. That should (and does) generate more than enough gasses to work the action.