I've read a few posts, checked FAQ 2, and a few other places about the notched hammers hitting the firing pin, bending the retainer, and chewing up firing pin when used with the standard carrier. I do notice on my Bushmaster CAR that when I pull the charging handle it does seem pretty gritty once the hammer starts getting pushed down, but it's not catching on anything to the point I can turn loose from the charging handle and it won't slam forward again. I've polished up the hammer face and all the mating surfaces on the FCG, so the trigger is nice and smooth, so I don't feel the need to do the 15-minute trigger job and cut the hammer spring. I did bend the springs a little bit on the hammer and trigger, though, but it still resets just fine and has plenty of force to pop primers.
Anyway, I know DPMS has the smooth-top hammer for $20, but is this really a necessity? Can I just grind down the notches a bit to smooth things out and call it good? I hate to be a cheapskate, but with me being the only source of income for our family, I need to save all the $$$ I can. If I can fix the grittiness/eliminate the possibility of binding with my 8" grinder or dremel and buffing wheel, I'll do it.