Video showing the process of Lapping an upper AR-15 receiver and bedding a barrel using Loctite 620. All done to improve accuracy and consistency in the AR-15 platform.
Video:
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If that's a bear Creek barrel that's why your moa is off. Cause bear Creek barrels fucking suck. There fucking trash
Can anyone tell me what the product is that is holding his upper receiver in the vise?
If you have that much free movement time for a new upper. Aluminum is a recyclable metal. Buy a new upper for anywhere from $39-$200 depending on the size of your wallet.
Head spacing is already determined from bolt and barrel lockup. NOT the receiver trimmed back. You "might have feeding issues if ramp cuts in receiver does not match up to barrel. But headspace IS NOT SCREWED UP JUST BY LAPPING
Stop breathing into the mic
You only need to use this process when using Anderson uppers with Bearcreek barrels..spend a little more money..buy top quality parts..and you will never have to do this
How do you take them off ??????
This makes no sense. Just buy a new upper, yours is clearly no good. Better off having to press fit the barrel then have all the slop.
Thanks for the post.
Headspace in an AR is not determined by barrel setback from lapping. It's determined by bolt head to barrel extension lockup.
First thing if that's a battle Creek barrel. That's the reason your moa is way off as you say. Because battle Creek barrels are fucking junk. But you get what you pay for. If you're are using cheap parts and junk ammo your moa is going to suck. Using the loctite not going to do a fucking thing. But cause a bunch of headaches done the road. You might want to try buying better parts. That was the most fucking retarded thing I seen so far. Moron
Many are under the impression that a locking material like LocTite is needed- IT IS NOT. The torque holds the nut to the receiver. I have never, ever seen a loose barrel in the military. As an armorer I have seen thousands of overused guns. YES the facing of the upper is needed especially for long range shooting as it aligns the barrel to the upper. Facing will NOT change the headspace as the headspace is integral with the barrel. The barrel MUST fit snug to the upper and the best fit is a slip fit. We used .001 stainless shim stock wrapped around the barrel extension to fit sloppy barrels for accuracy guns as even .001 barrel shift when assembling will cause a lot of scope issues at long range. Within MIL-SPEC is a joke as it is the MAXIMUM and minimum allowable specification and still work.. FYI The shear point for a barreled upper is the last thread on the upper behind the barrel nut.
How much difficulty will be encountered when it's time to remove the barrel?
A better method is one thou, stainless shim stock, for the usual loose forged uppers, it so far has worked for me every time, one rap around barrel extension, then add slip joint compound , just a little, a nice concentric press fit. And stainless steel will never melt.
Rare is it that an barrel extension fit nice and tight. It is the Best case though.
Both lapping the upper and shims, have tightened up groups with some of the kids I work with.
Headspace btw is a function of bolt and barrel extension, the threaded area of an upper doesn’t.
It is a best practice to remove as little as possible, just knocking off high spots and machine marks.
All this adds say 1/4 hour bench time at most, and say one dollar in parts.
Funny how it makes some upset?
Wonder if they have ever built a sub Moa semi upper?
Locktite not cool.
Cool simple vid, fuck all these comments especially from these 100yr gunsmiths that don’t know that loctite is a brand and there’s a difference between threadlocker and retaining compound.
There are two types of people in the world.
Type one thinks , "You have to do it this way because that's how I was taught, because I was told so!"
Type two, thinks.
Not sure about the Loctite, but I'm definitely going to give the lapping a try
Don't know about putting loctite, but I would have used Aeroshell 33 on that bad boy.
I am a REAL Gunsmith… 45 years now…. Never put Loctite on a AR barrel yet… Buy quality parts and there is never a problem… This hack bumped his head somewhere…Orange County Gunsmith. ocgunsmith.com
just jb weld…fuk it
Quality parts will serve you better than trying to correct cheap manufacturers sloppiness.
Great video! I think most of the people leaving comments claiming to be "Professional gunsmiths" and slamming the use of loctite 620 are missing the point. In the video, this man is not using threadlocker on the threads. He is using cylindrical sealer to close the gap on the barrel shaft. I didn't see him put any "Thread locker" on the threads. Also, just because it's Loctite brand doesn't mean that it's threadlocker. That company makes more then just thread locker…. LOL
2 issues with the video. If you are lapping the receiver to get consistent even surface, why would you stop short of a complete lapped surface. And the Loctite. That's just not good advice. Antiseize or a good grease only. Some poor guy is going to loctite the barrel nut and "That's what I saw on YouTube". I guess the 2 issues is the video.
Thats not how any of this works
That breathing whistle tho
Green loctite on the barrel extensions been used for a while now. Nothing crazy about it. The lapping tool and potential head space problems is something to be wary about. If you're nervous use the old school shim method. Good video nonetheless
How could headspace be affected by shortening this threaded area? I thought headspace was dictated by the distance between the boltface and the shoulder, which depends upon the lockup of the bolt into the barrel extension, neither of which should be affected by shortening this thread. Am I wrong?
I have never in my entire life ever ever heard of someone doing this. You really should take this video off cause some newbie will listen to you and ruin their upper at minimum or if you change the headspace dimensions, kill someone. Bad Bad Bad!!!
Interesting.. never once seen someone use green loctite
no, nobody try this. this is not the correct way to fix a firearm at all. you pretty much just jb welded your barrel in. not correct.
🤦♂️ Please just stop. Don't used Loctite there are way better compounds made specifically for barrel bedding. Though the lapping was done ok and safely you really need to add some kind of grease to. Those threads for the barrel nut, shit I would even give you credit for using. Tetra gun grease on the threads.