09-25-2019, 08:04 PM
A5BLASTER Wrote:I lapp any and all uppers. Not so much cause I think it makes it more accurate but more so to keep the parts square for the bolt lock up and even stress on the bolt lugs.
I guess I should have thought about this earlier as I now have 2 enhanced uppers (M4E1 and a M5E1), but I do see they sell lapping tools for the enhanced uppers also.
Thanks for the help folks.

