Safety Issue On AR Rifle Building

[bwframe]

Very interesting topic of conversation!

Sounds like the lapping tool is the way to go for this work. Is there any other simple "shade tree" mechanic way this is done?

Wonder if there are any published or linked before and after results of the use of this suggested technique? For lug damage/wear or for accuracy?

Along the same lines, what does INGO think of lubing the barrel nut and or "seasoning" the barrel nut and receiver threads when torquing?

 

[JeepHammer]

Very interesting topic of conversation!

Sounds like the lapping tool is the way to go for this work. Is there any other simple "shade tree" mechanic way this is done?

In the Marines, we chucked up the uppers on a mandrel between centers, with an under cut on the mandrel, and just faced off the upper.
Not exactly a work bench option.

Wonder if there are any published or linked before and after results of the use of this suggested technique? For lug damage/wear or for accuracy?

It's know pretty well by accuracy builders, NM rifles, speed guns and the like.
The Guild forums cover it pretty well.

There is a ton of failure to feed or failure to fully battery threads, and a bunch of them on home built rifles.
It's a fitting issue, the better the parts fit, the less run issues you have.

Along the same lines, what does INGO think of lubing the barrel nut and or "seasoning" the barrel nut and receiver threads when torquing?

Steel on aluminum torqued hard rather than fitted... The choice is yours.

 

[Dean C.]

One of the many many reasons I won't ever consider building my own, I will just pay the professionals to do it for me (LWRC being my preferred rifle)

 

[Ggreen]

One of the many many reasons I won't ever consider building my own, I will just pay the professionals to do it for me (LWRC being my preferred rifle)

very few production rifles have this done.

 

[Ggreen]

I see this more as an accuracy issue than safety. Accuracy because it trues the barrel to the reciever reducing any slop or chance of deviation between optic and barrel.

IF it were a safety issue the thousands of out of spec 29 dollar uppers people put together would be popping lugs on the 60 dollar bolts, it's just not happening with any frequency. I think the real safety issue is the flood of Chinese fcg's... I've seen some real gnarly triggers lately