308 AR Build Problems

[l15punk]

Hi all,

This is my first full AR build up and i am having a problem installing my barrel. the barrel extension is very tight inside the receiver, I can maybe get it in about 1/3 of the way. Is it normal for it to be this tight? If so what can I do about it. The receiver is a Fulton Armory Titian upper and the barrel is from Bison Armory. I will try and attach some photos. Thanks

[baih777]

i usually apply a thin coat of moly grease. also check the threaded area in the inner dia to see if their is a burr after the threading was done.
my DPMS 308 both just slid in nice.

[baih777]

also before you install the barrel check the barrel nut fit. make sure you got the right one.. you dont want to scratch that new barrel

[Hoop]

That happened to me on one. I lightly sanded it, greased it w/moly grease and then tightened down the barrel nut. Worked fine.

[kcstott]

Yeah it's just a touch to large you can either lightly sand the ID of the receiver or the OD of the barrel. And I mean lightly. 320 grit and just a little bit and check the fit. being that close it may be just a burr or something else keeping it from going all the way home.

[ILVSMOG]

de-burr, moly grease (anti-seize), heat gun on the receiver.

Those 3, in that order, have cured any issue I've had. Beware trying to suck the barrel into the receiver with the barrel nut. That's a lot of load to put on a few threads, especially if there's another issue. (burr, etc.)

[kcstott]

de-burr, moly grease (anti-seize), heat gun on the receiver.

Those 3, in that order, have cured any issue I've had. Beware trying to suck the barrel into the receiver with the barrel nut. That's a lot of load to put on a few threads, especially if there's another issue. (burr, etc.)

I can see the barrel nut popping off clean with all the threads inside

[l15punk]

Thanks everyone for the help. I applied a bit of grease and some heat and it went right in. ImageUploadedByTapatalk1335578925.944012.jpgImageUploadedByTapatalk1335579003.975912.jpg

[mayday]

not on the topic but just put together first dpms 308.. bolt is extremely snug.. changed out compression rings. Even tighter.. is this normal.. action works thru but do not want to lose half my face on first push thru barrel. just use to the work of a 223 is it suppose to be this tight??? just asking since your working on similalr metal...

[molasses2k]

My .308 DPMS bolt was extremely tight when new- I lubed and cycled the crap out of it for about 20 minutes and it loosened up-
You meant that the bolt is snug in the BCG, right? That worked for me-

[ChrisToad]

Like most aspects of my life... put a little lube on it. Glad you got it to fit!

[fxjets]

I had the same DPMS 308 bolt issue also, I removed one gas ring for the first 50 rounds, then reinstalled it. Worked great.