will this upper work with my bolt? AR question

[lazyman]

I have a bushmaster bolt and would like to know if I buythis http://www.bushmaster.com/shopping/uppers/vur.asp

and buy a mid length gas barrel put it together will my bushmaster bolt that I already have work?? or do I have to check headspace??

[bwiese]

This looks just to be an ordinary flattop upper receiver, nothing special. (You'll likely find it cheaper elsewhere.)

Note this receiver does not have the M4 feedramps. If you get a barrel w/M4 feedramps, the upper receiver should have them too (and vice versa).

Neither the upper receiver nor the bolt carrier on AR type rifles determine headspace. That is determined by the fit of the bolt itself in the barrel extension - the latter of which is affixed to the barrel when you buy it (just about all AR bbls have bbl extension affixed, it's a major thing to put one on a barrel otherwise, and no one really ever changes them).

All quality AR bbls and bolts should be made to spec so that a different brand of bolt and barrel will operate just fine.

It can be nice to buy the bbl and bolt from same vendor to avoid any possible tolerance stacking issue, and possibly have the best fit (i.e, bolt specifically matched to bbl extension for match guns). Some vendors will sell you a matched bolt + bbl set. For ordinary shooting purposes (your standard 16" carbine, for example) you don't have to worry about these fine details.

I've never had problems with Bushmaster, Colt, Armalite bolts in Bushmaser, Colt, etc bbls. Quality bbl and bolt vendors (Stag, Denny's Guns, BravoCo USA, DelTon) won't cause you any worry. I personally would avoid Model1, Sherluk, M&A parts, Olympic Arms and other 'bottom feeders'.

All AR owners should have a milspec FIELD chamber gage: if it closes on the gage you have problems.

[mike452]

This thing is expensive! I got a Mega just like it for 1/2 the price. Don't put it together yourself lazyman! I got Randall at www.ar15barrels.com in Los Angeles installed for me. He did a good job installing the barrel and free float handguard for around $30.

[lazyman]

thanks mike for the lead. Bwise damn, you and ted are the man

[bwiese]

Bwise damn, you and ted are the man

Um, we are not siamese twins and are entirely separate individuals

[bwiese]

Get yourself a field gauge from Brownell's. Go and No-Go are intended more for barrel makers.

Damn, that's what I meant to say - 'FIELD'. Brain-fart. Gettin' old. Earlier post edited. Thanks for catching.

I bought the set of 3 in 1998.

[lazyman]

Ted, do these CMT uppers have m4 feed ramps? I'm trying to build a uber cool AR and want all the neet stuff, 1:7 twist, m4 ramps, a3 upper etc....

[SemiAutoSam]

thanks mike for the lead. Bwise damn, you and ted are the man

I think you need to buy a vowel.

[lazyman]

Hey thanks ted for the link. I think I'm gonna go with a bravo upper coupled with a dennys barrel.