Buffer Tube Size > AR Discussions

Posted: 10/18/2007 6:06:14 PM EDT

I jsut read a post about lower receivers claiming that RR and Bush have commercial size buffer tube and Stag/CMT have a mil.spec tube.

If this is true I am very confused. I have a few RR 6pt collapse stocks. My VLTOR Modstock will not fit the RR tube. My Magpul CRT will not fit the tube. Both are 2 tight. The Modstock and the CRT fit the tube the Modstock kit came with.

Did I fk up and get both Magpul & Modstock as commercial size & not mil.spec?

FYI I am in NY so the RR were LE appropriate LE orders. Does RR sell mil.spec to LE and the rest commercial grade? If so it dosent make sense 2 me!

Posted: 10/18/2007 6:10:23 PM EDT

[#1]

A commercial sized CTR will fit on a MilSpec sized tube, with a small degree of looseness. Conversely, a MilSpec sized CTR will be too small to fit a commercial sized tube.

Posted: 10/18/2007 6:13:52 PM EDT

[#2]

Sorry for my ignorance.....so a commercial size tube is larger than a mil.spec? Which is stronger?

Posted: 10/18/2007 6:16:10 PM EDT

[#3]

Quoted:
Which is stronger?

mil-spec

Posted: 10/18/2007 6:18:13 PM EDT

[#4]

Quoted:
I jsut read a post about lower receivers claiming that RR and Bush have commercial size buffer tube and Stag/CMT have a mil.spec tube.

If this is true I am very confused. I have a few RR 6pt collapse stocks. My VLTOR Modstock will not fit the RR tube. My Magpul CRT will not fit the tube. Both are 2 tight. The Modstock and the CRT fit the tube the Modstock kit came with.

Did I fk up and get both Magpul & Modstock as commercial size & not mil.spec?

FYI I am in NY so the RR were LE appropriate LE orders. Does RR sell mil.spec to LE and the rest commercial grade? If so it dosent make sense 2 me!

That's because Vltor stocks only fit mil-spec tubes & you must have a CTR stock meant for a mil-spec tube. One can buy a CTR for either...you just have to know what spec your tube is before you buy the stock. RRA's come with commercial tubes.

Posted: 10/18/2007 6:25:54 PM EDT

[#5]

Quoted:
Sorry for my ignorance.....so a commercial size tube is larger than a mil.spec? Which is stronger?

Correct, a commercial diameter tube is slightly larger in diameter than is a MilSpec tube.

If you have a MilSpec tube, you can utilize a commercial sized CTR, which will lock up tight to the tube via the tensioning lever. Unfortunately, the reverse doesn't hold true with MilSpec CTR's and commercial tubes.

Posted: 10/18/2007 6:28:44 PM EDT

[#6]

why are there 2 different size tubes?

Posted: 10/18/2007 7:01:55 PM EDT

[#7]

Quoted:
why are there 2 different size tubes?

Manufacturer product differentiation? Point cost? Then again, some AR manufacturer's are set up for .gov contracts and are required to construct/produce products to military specifications. Thus, whatever is remaining after .gov contract fulfillment is utilized for civilian products.

CMT is a .gov contractor, and produces STAG, so it would thus follow their tubes would be MilSpec.

Just a guess...

Warning

Confirm Action

[ARCHIVED THREAD] - Buffer Tube Size

[ARCHIVED THREAD] - Buffer Tube Size