AR Buffer Tube question....

Skans · February 28, 2013, 03:47 PM

Is there really any difference between a mil spec buffer tube made out of 6061 vs. 7075 aluminum? The 7075 tubes seem to sell for about twice what the 6061 tubes sell for.

Heck, if there is really that much difference, maybe I should by a steel chromoly tube.

Quadpod88 · February 28, 2013, 03:57 PM

One word...rust

AGENT TIKKI · February 28, 2013, 04:44 PM

um.....when's the last time you saw aluminum rust?

the difference is strength, 7071 is stranger than aluminum. I believe milspec tubes are 7071. Honestly for the recreational shooter, a 6061 tube is fine.

Just check out how many forearms are made in 6061.

Skans · February 28, 2013, 06:31 PM

I think he was referring to my reference to steel buffer tubes - they actually exist.

marine6680 · February 28, 2013, 06:47 PM

I think he meant the steel would rust.

But yeah, the 70 series is stronger than the 60... if all you plan on doing in plinking and range use, 60 is fine.

For serious use, the 70 is better, especially if you plan on doing lots of hard training with the rifle. When I was in the Marines, we used the rifle to two man lift a 3rd person over walls, plus melee training for close quarters and running out of ammo... I don't know about the carbines, but the A2 was a tough rifle... Most people will never even get anywhere near that level intensity of use with the rifle.

Skans · February 28, 2013, 06:53 PM

I think you've convinced me to go with 7075. Some things I just don't want to compromise on.

I thought that all of the A2 rifles were built around 6061 forgings, weren't they?

AGENT TIKKI · February 28, 2013, 06:56 PM

Maybe, but, you were asking the difference between 7071 and 6061 aluminum. Either way, if you do want the strongest, make sure you get the milspec type, not commercial tube. Milspec is smaller in diamter externally ergo its stronger.

chris in va · March 1, 2013, 01:47 AM

Plenty of mountain bikes are made with 6 series aluminum. I'm sure it's fine for a flippin buffer tube.

madcratebuilder · March 1, 2013, 11:22 AM

A true mil-spec RE is FORGED 7075.

Most 6061 RE's are extruded. You would have to work very hard to cause a 6061 RE to fail. The forged 7075 is a stronger part no doubt, but is it really needed? If price is near the same I would like the 7075 but I'm not going to pay a whole lot more for it.

Don't confuse RE's advertised as "mil-spec diameter" to be forged 7075, they are not.

February 28, 2013, 03:47 PM	#1
Skans Senior Member Join Date: November 20, 2008 Posts: 6,250	AR Buffer Tube question.... Is there really any difference between a mil spec buffer tube made out of 6061 vs. 7075 aluminum? The 7075 tubes seem to sell for about twice what the 6061 tubes sell for. Heck, if there is really that much difference, maybe I should by a steel chromoly tube.

February 28, 2013, 03:57 PM	#2
Quadpod88 Member Join Date: February 28, 2013 Posts: 62	One word...rust __________________ *God made all men, but it was Sam Colt who made them equal.*

February 28, 2013, 04:44 PM	#3
AGENT TIKKI Member Join Date: September 18, 2010 Posts: 49	um.....when's the last time you saw aluminum rust? the difference is strength, 7071 is stranger than aluminum. I believe milspec tubes are 7071. Honestly for the recreational shooter, a 6061 tube is fine. Just check out how many forearms are made in 6061.

February 28, 2013, 06:31 PM	#4
Skans Senior Member Join Date: November 20, 2008 Posts: 6,250	I think he was referring to my reference to steel buffer tubes - they actually exist.

February 28, 2013, 06:47 PM	#5
marine6680 Senior Member Join Date: July 24, 2012 Posts: 361	I think he meant the steel would rust. But yeah, the 70 series is stronger than the 60... if all you plan on doing in plinking and range use, 60 is fine. For serious use, the 70 is better, especially if you plan on doing lots of hard training with the rifle. When I was in the Marines, we used the rifle to two man lift a 3rd person over walls, plus melee training for close quarters and running out of ammo... I don't know about the carbines, but the A2 was a tough rifle... Most people will never even get anywhere near that level intensity of use with the rifle.

February 28, 2013, 06:53 PM	#6
Skans Senior Member Join Date: November 20, 2008 Posts: 6,250	I think you've convinced me to go with 7075. Some things I just don't want to compromise on. I thought that all of the A2 rifles were built around 6061 forgings, weren't they?

February 28, 2013, 06:56 PM	#7
AGENT TIKKI Member Join Date: September 18, 2010 Posts: 49	Maybe, but, you were asking the difference between 7071 and 6061 aluminum. Either way, if you do want the strongest, make sure you get the milspec type, not commercial tube. Milspec is smaller in diamter externally ergo its stronger.

March 1, 2013, 01:47 AM	#8
chris in va Senior Member Join Date: December 26, 2004 Location: Louisville KY Posts: 11,718	Plenty of mountain bikes are made with 6 series aluminum. I'm sure it's fine for a flippin buffer tube.

March 1, 2013, 11:22 AM	#9
madcratebuilder Senior Member Join Date: November 2, 2007 Location: Northern Orygun Posts: 4,864	A true mil-spec RE is FORGED 7075. Most 6061 RE's are extruded. You would have to work very hard to cause a 6061 RE to fail. The forged 7075 is a stronger part no doubt, but is it really needed? If price is near the same I would like the 7075 but I'm not going to pay a whole lot more for it. Don't confuse RE's advertised as "mil-spec diameter" to be forged 7075, they are not.