AR buffer tube Question

[YBNORMAL]

sorry if this has been covered before. does anyone have the diameter measurements for the comercial and milspec buffer tubes, im looking to get a CTR stock and dont want to get this wrong since i will probably look for it online. I have a S&W 15 in 5.56 but im afraid that doesnt mean it has what its supposed to have since things like that happen alot. also I have heard that you can run one style stock on the other size buffer tube and get a tighter fit? is this true and if so, which way does it go? com. stock on mil-sp tube for tight fit, or the other way around.

Thanks for any insight you might have.

[Big Dog]

Milspec is 1.148"
Commercial spec is 1.168

You can tell by looking. If the tube is a bit smaller than the threads - it's mil-spec, if the tube is the same as the threads - commercial.

[Bravo Whiskey]

Milspec is 1.148"
Commercial spec is 1.168

You can tell by looking. If the tube is a bit smaller than the threads - it's mil-spec, if the tube is the same as the threads - commercial.

Bingo, 100% correct.

[YBNORMAL]

Thank you gentleman!

[Yoder]

sorry if this has been covered before. does anyone have the diameter measurements for the comercial and milspec buffer tubes, im looking to get a CTR stock and dont want to get this wrong since i will probably look for it online. I have a S&W 15 in 5.56 but im afraid that doesnt mean it has what its supposed to have since things like that happen alot. also I have heard that you can run one style stock on the other size buffer tube and get a tighter fit? is this true and if so, which way does it go? com. stock on mil-sp tube for tight fit, or the other way around.

Thanks for any insight you might have.

I found this on AR15.com check it out:

http://www.ar15.com/forums/topic.htm...f=118&t=445399

[Big Dog]

I found this on AR15.com check it out:

http://www.ar15.com/forums/topic.htm...f=118&t=445399

Good find, I forgot about the slanted tube end (I have no commercial tubes)!

[levib]

Milspec is 1.148"
Commercial spec is 1.168

You can tell by looking. If the tube is a bit smaller than the threads - it's mil-spec, if the tube is the same as the threads - commercial.

Thank you for that clarification!

[YBNORMAL]

i really need to buy a calipers, but looking at my tube, it appears that there is a shoulder after the treads that is the same or may be a little smaller than the threads, and then the tube steps up a little then stays the same length till the end, it doesnt have an angled end like some have posted on AR15. thanks for all your help guys, i need to find someone that has both ctr stocks and just see how they fit.....or buy a caliper, with the calipers i assume i would want to measure the tube near its center, between the length of adjustment holes?

[Big Dog]

i really need to buy a calipers, but looking at my tube, it appears that there is a shoulder after the treads that is the same or may be a little smaller than the threads, and then the tube steps up a little then stays the same length till the end, it doesnt have an angled end like some have posted on AR15. thanks for all your help guys, i need to find someone that has both ctr stocks and just see how they fit.....or buy a caliper, with the calipers i assume i would want to measure the tube near its center, between the length of adjustment holes?

Take a picture as close and in focus as possible and we'll tell you!

Run a straight edge, (something like a index card, machinist scale) from the tube to the threads. If the straight edge gets caught by the threads it's milspec. If it runs over the threads, it's commercial.

[YBNORMAL]

Ahhhh, thanks big dog, even i cant screw that one up!