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4/16/2026 11:59:05 AM EDT
Little backstory. I had some trouble with the barrel in this build. Fired rounds would go in and out on their own, no issue. Chambered, but unfired rounds would not extract without excessive force (hitting the butt of the rifle on the ground while working CH). Everytime this happened, the projectile would be left in the barrel. The case would come out along with powder going everywhere. Mind you this is using a Lilja 6.5 Grendel barrel from Six Sigma Arms with a properly head-spaced bolt. The first time this happened I was away from home and took it to a nearby gunsmith who bore scoped it and found a carbon ring. He buffed it out and said it was good to go. Same issue arose a few rounds later if not the very next round.

After several at-home attempts of cleaning and playing with AGB, I decided to take it to another professional.  Went to a semi-local gunsmiff who had pretty good reviews online. Had him borescope it, go through it etc.. He took it apart and shimmed the extension to what he said was good. He did tell me after picking it up that it had excess Cerakote in the upper that made such a tight fit. Didn't completely but that but ok. Got it home and immediately had the same issue. No worries, at that  point I figured it was a barrel issue. So I'll send it back to the manufacturer. After taking the upper apart, I found out he had a little trouble getting the barrel out of the upper. Looks like he took a flathead as a wedge and whacked it out. Banged the extension threads all up. For what it's worth, I had some trouble getting this barrel in. Upper in the oven and barrel in the freezer still took some convincing to fully seat. Not like there was a ton of Cerakote in the receiver, but it still took a whack or two to get it all the way in. I did however, get the barrel out using a wooden dowel, same as I always do.

I sent the barrel back to Lilja  and got it back with a clean bill of health. I was told there wasn't anything wrong with it, but it was pretty dirty. I haven't got the upper back together, as you can see I'm unsure of using the receiver.
So, still at a loss on the barrel at the moment.

Is this receiver worth using? Barrel nut seats fine, no issues there that I am aware of.






4/16/2026 12:52:27 PM EDT
[#1]
Absolutely, I'd use that receiver.

Barrel issue sounds like too tight a chamber, or too short leade.
4/16/2026 1:12:04 PM EDT
[#2]
I'd use it as well
4/16/2026 1:24:43 PM EDT
[#3]
Quote History
Originally Posted By JoeDevola:
Absolutely, I'd use that receiver.

Barrel issue sounds like too tight a chamber, or too short leade.
View Quote


I assumed chamber issue but I don’t know enough about barrels. I’m not sure what else it could be but Carson at Lilja didn’t think it had an issue.
4/16/2026 1:40:44 PM EDT
[#4]
Originally Posted By radar1225S:

Is this receiver worth using? Barrel nut seats fine, no issues there that I am aware of.

View Quote


If it seats, it yeets. Send it.

Maybe clean up and lap that surface so the barrel extension shoulder has good  square contact.
4/16/2026 1:48:28 PM EDT
[#5]
I planned on lapping it. I just have the cheap Wheeler kit but I guess it’ll do.
4/16/2026 3:57:41 PM EDT
[#6]
Sounds more like an ammo issue.  What ammo sticks in there?
If life was easy nobody would quit.
4/19/2026 9:24:04 PM EDT
[#7]
Hornady Black 123gr ELDM was the main one, it also happened to a custom loaded 120gr Barnes TTSX

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