Ar upper & barrel extension tight fit

[KaNuckles]

My AR barrel fits extremely tight into the receiver. So tight I can't get half way in by hand. Is it cool to try a little grease and a few light taps with soft faced hammer?

The upper is aero precision and the barrel is: http://palmettostatearmory.com/index.php/ar-15-05/upper-parts/barrels/16/16-5-56-nato-1-7-chrome-lined-chrome-moly-vanadium-hpt-mp-mid-length-gas-a2-style-profile-barrel.html

[Caster]

It's NOT cool to put it together WITHOUT a little grease, so yeah, take your finger and smear a very light film of high quality grease on the extension and the threads also.

[Guest nysos]

Do you have any visible high spots or burrs? It shouldn't be THAT tight, just snug. The grease should be fine though.

Edited August 24, 2012 by nysos

[KaNuckles]

Thanks guys. I would guess the grease would need to be moly grease withou any graphite?

[mikegideon]

I've never had one that tight. Something is out of spec. I doubt that I would put it together like that. To each his own.

[Dolomite_supafly]

Try putting the barrel in the freezer for an hour or two. And right before you go to put the barrel in the receiver put the receiver in boiling water for about a minute.

The barrel will shrink by a few .001" in the freezer and the receiver will grow by a few .001" in the hot water.

Hopefully with is enough to drop in. If it doesn't just drop right in place then something definitely is out of spec. I have seen tight fits before but this generally is enough to get by it.

If it doesn't go together measure the shank with a micrometer and post the results.

Dolomite

[KaNuckles]

Thanks a lot. I will try that and post results.

[KaNuckles]

The hot/cold treatment worked. Fell to gether like nobody's business. I wrapped the barrel up in a towel to let it warm up slowly and not condensate. Now that everything is up to room temperature, I can get it all the way but about 1/16 now by hand now. Thanks for the info.

[Dolomite_supafly]

Should make for a nice shooting gun.

Dolomite

[Guest FIST]

My AR barrel fits extremely tight into the receiver. So tight I can't get half way in by hand. Is it cool to try a little grease and a few light taps with soft faced hammer?

The upper is aero precision and the barrel is: http://palmettostate...ile-barrel.html

I just had the same problem last night with an Aero Precision upper. Greased it and tapped lightly with the plastic end of my gunsmiths hammer. I was using a Colt barrel though. Did you happen to order yours from Brownells?

[KaNuckles]

I just had the same problem last night with an Aero Precision upper. Greased it and tapped lightly with the plastic end of my gunsmiths hammer. I was using a Colt barrel though. Did you happen to order yours from Brownells?

I got the Palmetto barrel and the upper came from surplusammo.com. They don't carry the upper only anymore. It only comes in a matched set with a lower. I kinda thought the finish was a little thick on the barrel. But now I'm not so sure.