Bedding a tight fit receiver/extension?

[Drillboss]

I'm ready to put together my 12.7" Faxon barrel in a BCM upper receiver and I'm going to have to heat the receiver to get the barrel extension into it.

Is there any benefit or need to bed it with Loc-tite in this situation?

[Bigs28]

I've read you can freeze the barrel to but i have never had todo it

[Djgrendel]

In that case I doubt it will help much. But it won't hurt anything to add it to your assembly. You will have to heat the receiver to separate the barrel in the future anyway. More critical would be to ensure you have a square face on the receiver.

[Kswhitetails]

If it's tight enough that you cannot force it together by hand, then bedding will supply little, likely no advantage. Bedding the barrel extension is a method used in which you are using the bedding substrate material as a "shim" of sorts to take up the wiggle room between the extension and upper. It may provide some kind of lubrication when installing it though?

The real benefit at this point comes from ensuring the square/true receiver face. This should be checked and if necessary, trued before assembly. Good luck with your build!

[Drillboss]

Thanks guys. I went offline and got the same opinion from a trusted source. When things went together the first time, the pin missed the slot and I couldn't move it at all. After heating and beating with a wooden dowel, the next try caught the slot but didn't make up flush. I had to pull them together with the barrel nut. I feel pretty good about the fit without Lok-tite.

By the way, I trued the receiver face a few weeks ago, and again, the BCM uppers don't need much. I'll probably never buy anything else.

Not caring much for delayed gratification, I bedded the gas block, ran a few patches through the barrel, and took it out for an ops-check with a single round from the hip. Gun went bang, nothing blew up, and it locked back on the bolt face. Life is good. I'll zero the scope and try some groups after the weather improves.

Here's how it looks.

Pistol Build.jpg

9" handguard for now, since I had one on hand. Who knows what changes will come later.

[Kswhitetails]

Slick Willie!

[Les]

I'm using a BCM upper as well, they are indeed very tight, I might use some no-alox/penatrox before heating or freezing anything. It's what I use to mate electrical connections when I have 2 dissimilar metals and it also serves as a lubricant and works well.

[Drillboss]

I'm using a BCM upper as well, they are indeed very tight, I might use some no-alox/penatrox before heating or freezing anything. It's what I use to mate electrical connections when I have 2 dissimilar metals and it also serves as a lubricant and works well.

I have no idea what you just said.

[Tex Nomex]

I'm using a BCM upper as well, they are indeed very tight, I might use some no-alox/penatrox before heating or freezing anything. It's what I use to mate electrical connections when I have 2 dissimilar metals and it also serves as a lubricant and works well.

Might be better to use something without zinc. Either product is good for mating copper and aluminum, but zinc reacts with steel.

[grayfox]

Thanks guys. I went offline and got the same opinion from a trusted source. When things went together the first time, the pin missed the slot and I couldn't move it at all. After heating and beating with a wooden dowel, the next try caught the slot but didn't make up flush. I had to pull them together with the barrel nut. I feel pretty good about the fit without Lok-tite.

By the way, I trued the receiver face a few weeks ago, and again, the BCM uppers don't need much. I'll probably never buy anything else.

Not caring much for delayed gratification, I bedded the gas block, ran a few patches through the barrel, and took it out for an ops-check with a single round from the hip. Gun went bang, nothing blew up, and it locked back on the bolt face. Life is good. I'll zero the scope and try some groups after the weather improves.
Here's how it looks.

[ATTACH=CONFIG]11672[/ATTACH]

9" handguard for now, since I had one on hand. Who knows what changes will come later.

Lookin too good and too tempting!!! Nice going.

[Drillboss]

Lookin too good and too tempting!!! Nice going.

Thanks.

You gotta get you one, John has plenty of barrels on hand.

[VASCAR2]

Drillboss great looking pistol. I really likes the looks of that 12.7" barrel with that hand guard! Your not helping my addiction, I'm trying to resist the temptation of buying a 12.7" Faxon barrel.

[Drillboss]

Drillboss great looking pistol. I really likes the looks of that 12.7" barrel with that hand guard! Your not helping my addiction, I'm trying to resist the temptation of buying a 12.7" Faxon barrel.

See, you're not thinking about it right. The handguard came off of a 5.56 in the cabinet that I never shoot. The BCG I swapped out from my 20" Shilen.

From what I've seen of your posts, you've got almost everything you need to put one of these together for next to nuthin.

[Drillboss]

Faxon seems to be doing something right with their barrels. The weather improved quite a bit, so I went out to zero the scope and try a couple groups. My scope is a 1-4X Burris and it really doesn't match up that well with these old eyes. The reticle dot looks to be about twice the size of the target dots. That said, I got a group with American Gunner ammo under 3/4" at 100 yards. These are rounds 5 thru 13 thru the barrel.

Scan0027.pdf

[Les]

Might be better to use something without zinc. Either product is good for mating copper and aluminum, but zinc reacts with steel.

K-rap. Always believed it was graphite, not zinc.