Cherry seeks wisdom and guidance

[sgtrock82]

These last weeks have been my reintroduction, to the M4. I was issued one back in 98 while in the 82nd. I think we were the first regular army unit to get them and gottem brand new out of the boxes. It seemed all there was for acc. were RIS or RAS and M68 (aimpoint) and PEQ-2. I Have shot NRA Service rifle for several years now and have plenty of experience with competition (3 years @camp perry, 22 of 30 points toward distinguished riflemans badge) and the ar15. I decided to get an M4 style rifle for some fun, and found a whole new confusing world. I bought a new BM patrolmans carbine (save the tomatoes). From what Ive read I might have been better rolling my own, but what the hell I am here now so hereit goes. I have the rifle and a new RAS and an Aimpoint comp with out a mount (will have to do till get $$ for a newer model) What do you guy recommend improving from a technical stand point (springs, buffer, gas rings, anti rotation whatchamacallits,etc) Was suprised to find BM blessed this rifle w/ M4 feedramps, but not F marked front sight base and I am guessing, by how it zeroed not the tall post either. Gentlemen you may fire when ready.

[paradoc]

I have a BM Patrolmans carbine as well, I haven't needed to change anything, but I want to change a few things on it just to suit my own preferences.

Bushmaster has it's supporters and it's detractors just as all manufacturers.
The things that I want to change are the buttstock assembly (to one that is actually mil spec.) and get an A1 pistolgrip, mine has the A2 upper so I am sticking to irons for it.

There are as many opinions on ARs as shooters............

[sgtrock82]

I am unsure about the stock thing. I read all the posts pertaining to mil-spec and what not. I mic'd my stock and found the normal 1.170 tube dia. but the threads mic'd at 1.184 am i reading into this too much or does that .003 matter that much.

[paradoc]

if you are not planning on changing it out with an aftermarket stock using the original buffer tube is doesn't really matter.

Some get wound up pretty tight about in spec vs. out of spec parts and all.

[Robb Jensen]

I haven't seen a Bushmaster w/M4 ramps unless it was one of their gas piston versions. Or if a Bushmaster had an aftermarket upper receiver and barrel.

I'd recommend swapping to a MP tested bolt and keeping your Bushy bolt as a emergency use spare. Change to a ISMI buffer spring, H2 buffer, stake the M4 castle nut and carrier key better than stock. Add Crane 0-ring or MGI D-fender to enhance the extractor spring tension. Add a chrome silicon ejector spring. Add a 'Gapper' or swap triggerguards to a Magpul one.

[sgtrock82]

Thanks for the suggestions! I was suprised to see the M4 ramps, but they are there, seen the pics others have posted about them, compared it to my other ar15s and the ramps extend from the barrel extension into the upper, not dremel done. I work at the gunshop where I got it and it is new from BM. they've got in another, I will check it out. What is an ISMI spring? Where is a good source for these parts? Are there any headspace issues with swapping out bolts? Other suggestions welcomed, I am fishing for Ideas from those experienced with these.