Another lapping thread (would you still use this)

[CoryD]

Hey guys, I know you’re all sick of these threads. I know there are a lot of guys pro & a lot of guys against lapping receivers. After going back & fourth I decided I would just go for it & ordered a brownells lapping tool.

When I first received the tool it seemed like it had slight burrs & I just put the tool in my drill & slightly hit it with steel wool. I lubed the shaft really good, applied 320 grit compound on the face of the tool & slowly lapped BY HAND. I carefully removed it & cleaned tool & receiver every time before doing more.

I feel like the face came out really good. Seemed a bit out of true. Now as I was cleaning the inside of receiver I noticed a little ring in the receiver, looks like from the body of the tool after that skinnier area. I can definitely feel it with my finger nail. It clears the barrel extension. I’m not planning on junking the receiver but it’s going to be on a semi precision build rocking a vortex gen 3.
Do you guys think it’ll affect accuracy at all, or do you think it’ll be fine once the BCG group runs through it a few times?
Thanks - cory D

 

[Ravenworks]

You are way over thinking this.
Put it together, clean up any burrs or marks by hand and carry on

 

[lennyo3034]

Are you sure that wasn’t there before lapping? Have it in my Mega MML upper.

 

[Precision Underground]

ARs can be finicky but this doesn’t matter.

 

[Rocketvapor]

Is the BCG gonna TOUCH this mark?

 

[CoryD]

Are you sure that wasn’t there before lapping? Have it in my Mega MML upper.

It honestly could’ve been, almost looks factory because I didn’t really ruin any anodizing or scuffing.

 

[CoryD]

Is the BCG gonna TOUCH this mark?

I’m not sure. Looks like 1/2” before the barrel extension

 

[bfoosh006]

Don't worry about it , many of my lapped uppers have that... they all are shooters.

 

[CoryD]

**UPDATE**

my buddy brought over his aero precision upper receiver (to install a barrel/handguard). His had the same exact marks in it from the factory. So I assembled & bedded with 609 loctite.

 

[Luvman]

AR uppers have 2 different diameters. It was made that way.