[Silvertip 44]

I have two stripped DPMS receivers and plan to build two different configurations at some point in time. I am not in a rush since I already have a new Bushmaster XM15A2 20" target rifle.
The question is that when I purchase an upper should I get it complete with bolt and carrier? My concern is that if I purchase the upper and then use a bolt and carrier of different make it would have to be headspaced professionally wouldn't it?
I would like to get some of this stuff ironed out before I actually start.
My builds will be flat tops so that I can mount scopes or other optics closer to the bore and they will both be rifle length barrels. That is my plan anyway unless my son wants to use one of the receivers to build an M4 type carbine.

[junho806]

Originally Posted by Silvertip 44

I have two stripped DPMS receivers and plan to build two different configurations at some point in time. I am not in a rush since I already have a new Bushmaster XM15A2 20" target rifle.
The question is that when I purchase an upper should I get it complete with bolt and carrier? My concern is that if I purchase the upper and then use a bolt and carrier of different make it would have to be headspaced professionally wouldn't it?
I would like to get some of this stuff ironed out before I actually start.
My builds will be flat tops so that I can mount scopes or other optics closer to the bore and they will both be rifle length barrels. That is my plan anyway unless my son wants to use one of the receivers to build an M4 type carbine.

you really shouldnt have a problem with headspace if the upper and the bolt carrier are different brands
as long as both brands are reputable atleast
if your looking for a M4 type rifle you can check out mine in my sig


keep us updated on your rifles

[Dillinger]

Yeah, junho is spot on again. The upper is really much irrelevant to which BCG group you get, as long as you don't get some strange assed dimensioned version from "Ed's Machine and Liquor" or something like that.

Honestly, you could buy one Bolt and carrier group for .223/5.56 - then buy another bolt head in say, 7.62 x 39, use the same BCG and the same lower, slap on another upper that is chambered for the round and be good to go with a whole "different" rifle....

[rnds, on time & on target]

I also have a question, regarding early AR-15's, or more specifically the main hinge pin for the upper & lowers..i'm used to the matching, captive push-through pair..but i've recently aquired an early slab-sided model that looks exactly like a vietnam era M-16a1 (except without the bolt assist & auto trigger group) it's semi-auto only..i'm told the 'SP' that pre-empts the serial no. denotes a 'sporter' model but i'm fairly sure that this one was made before the AR's were even considered for sporting models, so..but anyway back to the question, it's main hinge 'pin' seems to be a horrible large-blade screwdriver looking affair, on both ends! i'm pressuming one end is an end-cap and that one would then use two screwdrivers to untighten said cap, but that did'nt seem to work and i dont want to risk damage..so, is this a stupid question, and i should just try harder..or is there some simple trick to this?..i'm workin the prob right this min, so a prompt reply would be much appreciated, cheers!

[matt g]

post approved, bump for rounds.