I agree with justlikeanyoneelse.

MK262 MOD1

I've also had good experiences with:

IMI M193
PPUM193
BH 75 gr. BTHP (223)
BH 77 gr. BTHP (223)
LC M193 (Fireball city)
LC M855
PPU M855

My personal preference go to round is the MK262 MOD1.

As soon as it gets back in stock, I'll be trying the BH 69 gr. 5.56MM.

Quote Originally Posted by Hop View Post
I got my upper on the cheap because the seller couldn't get his suppressor to fit. He didn't do much research on how to get it to fit before posting it for sale. Score!

I do have to ask what round works best in this upper?