02-26-2013, 11:19 PM
I 'borrowed' the one from my BCM 5.56 upper last week to finish my build with 18" AA barrel... I called around town today and thought I had one... went there to pick it up and they had a dozen or so ... (but they were rifle length... not mid... evidently, no one measured them when I called)
Anyway, I was about to head out and see if I could find one on line and just stopped by to chat with one of the other guys that works there and he said he has cut them down on several occasions with no problems. So I bought a couple of them and returned home.
I needed to cut it down from ~15" to 12"... so i straightened out the bends (as the cut had to happen right in between the bends) by drilling a hole the same size in a 2X6 and mounting the tube in a drill chuck... then I carefully pushed the tube into the hole at a low rpm... pushed it on through and increased the rpm while running the tube in and out of the wood block until it spun without wobbling.
Then, using my dremel cut off, I chopped it to 12" exactly... and finished the end nice and smooth.
Then I had to make the new bends ... I did that by using the same 2" piece of wood I used to straighten it. I pushed the tube in to where I wanted to make the bend and carefully made the bend... pulled it out and inserted the other end until it hit my mark and made that bend...
When I put the tube in the upper, the bolt didn't want to cycle really smooth... so I kept taking it out and making small adjustments to the bends until the bolt cycled smoothly.
I haven't taken it to the range yet, but will report back here when I do...
It seems to fit just fine... only thing I noticed is what looked like a slight flare on the bolt end of the tube (before cutting it off) was actually about 2 inches of machining done to that end of the tube about 1/8" inch in from the end. I didn't do that as i didn't have the tools to actually do the machining. If anyone's interested, I can post a pic or 2 of the other one I bought so you can see what I am talking about...
Anyway, I was about to head out and see if I could find one on line and just stopped by to chat with one of the other guys that works there and he said he has cut them down on several occasions with no problems. So I bought a couple of them and returned home.
I needed to cut it down from ~15" to 12"... so i straightened out the bends (as the cut had to happen right in between the bends) by drilling a hole the same size in a 2X6 and mounting the tube in a drill chuck... then I carefully pushed the tube into the hole at a low rpm... pushed it on through and increased the rpm while running the tube in and out of the wood block until it spun without wobbling.
Then, using my dremel cut off, I chopped it to 12" exactly... and finished the end nice and smooth.
Then I had to make the new bends ... I did that by using the same 2" piece of wood I used to straighten it. I pushed the tube in to where I wanted to make the bend and carefully made the bend... pulled it out and inserted the other end until it hit my mark and made that bend...
When I put the tube in the upper, the bolt didn't want to cycle really smooth... so I kept taking it out and making small adjustments to the bends until the bolt cycled smoothly.
I haven't taken it to the range yet, but will report back here when I do...
It seems to fit just fine... only thing I noticed is what looked like a slight flare on the bolt end of the tube (before cutting it off) was actually about 2 inches of machining done to that end of the tube about 1/8" inch in from the end. I didn't do that as i didn't have the tools to actually do the machining. If anyone's interested, I can post a pic or 2 of the other one I bought so you can see what I am talking about...