Completely stumped-yet another gas function question.

[A5BLASTER]

LRRPF52, JP 18 inch is rifle length gas.

Could it be something to do with the ambi bolt release? I ask because I have never used a ambi bolt release so not sure if they can cause a problem.

[Bobke]

The Seekins ambi release could be an issue-I'm not certain at this point, though that's where it was hanging up before bumping gas up. Young carrier is about 5 years old-is there a dimension I could compare to? I'm using 3 older, and 5 newer ASC mags that have required quite a bit of massaging to get them to work, but no longer seem to be an issue after working over flare forward of feed lips, dropping the front of mag for ample clearance and squeezing them to fit freely in 3 different lowers. ASC needs to shoot what they're selling, as these were completely non functional as delivered new in wrapper. QC seems to be only cosmetic, and not focused on functional reliability. Know that's been covered elsewhere, and they're GTG, once worked over. PITA, this has been, but a teaching moment, nonetheless. And not quite put to bed, just yet.

[A5BLASTER]

If the bcg is five years old and you haven't ever had this issue before while useing it, my thinking is the problem isn't with the bcg.

Funny you should say that about the asc mags I have their five round mags I bought from PF and have never had a issue with them.

[LRRPF52]

LRRPF52, JP 18 inch is rifle length gas.

From the OP:

Have a new to me JP ultra light Supermatch 18" rifle gas barrel that has been installed in a known to function upper/lower setup.

I don't think I've ever seen a JP 18" barrel without RLGS in the 14 years that I have dealt with the company.

JP is one of the few companies I can recommend sight unseen, which is extremely rare.

Bobke, try a different magazine. Are you lubed up well with a thick oil, not one of the snake oil types of recent fame, but something like Slip200, motor oil, or even CLP?

[A5BLASTER]

Yes I know I have one.

I read your post and it looked as though you were saying it had a mlg.

That's why I posted it was rifle length gas.

[Bobke]

This 18" JP is RLGS-never described as other than, though my other AR319 mid gas Lilja barrel on a carbine length buffer, H2 and SLR gas block was a whole lot easier to set up gas and go. Use either Slip 2000 and/or Fireclean on carrier and bolt, so should not be dry, though gas rings in relatively new JP bolt were a snug fit in Young BCG. Could be they're settling in, as well. Have a brand new SLR adj GB to install tonight, with a fresh gas tube, which I'll take to next range trip to see which functions with 100% reliability. Modified ASC mags now work, only others I have are older C Products and one or two from Alex Arms. Have a mil spec bolt catch to install as well, eliminating yet another variable. Still a work in process. Thx for continued feedback.