Need some Expert advice and opinions from fellow Members.

I would like to have minimum machining done to maintain as much carrier weight/mass as possible. Can the area to expose firing pin collar be done only, or is opening of rear portion of carrier also required? If so, I have read that only a 1/4" or so may be necessary, rather than removing 1"+ of the closed rear.

What are Your recommendations?

To avoid the obvious question; NO.. NONE of my AR's have m16 carriers installed.. ALL conform to BATF regs.. this question is posted for planning of future project only.

Thanks in Advance for your feedback!
Bravo5-2

*Have also posted the question to KKF in Industry Forums.

the area covering the firing pin does NOT have to be done.  (Lotboy's new Colt post ban came with the firing pin collar in M16 fashion)

If you want to be perfectly legal you need to take enough material off of the rear so that it is incapable of tripping an auto sear.

If it were me, i wouldn't go to the trouble of machining it at all.  (assuming that you have no other 16 parts)