View Full Version : Inner Barrel Widths

03-16-2004, 09:42 AM
Are stock inner barrel widths for TM Armalights 6.04mm? If so, I'm going to have to pick up a 6.03mm for my SPR conversion kit. The 6.04mm will not fit all the way down the barrel.

If my barrel is too long, are there any issues with cutting the end to make it fit?

03-16-2004, 10:23 AM
My understanding is that stock TM inner barrels have an inner diameter of 6.08mm.

I've never reduced the length of any inner barrel, but have heard of it being done successfully. One thing people often mention when they're talking about making such a modification is the need to properly "crown" or "de-burr" the end of the barrel.


03-16-2004, 11:15 AM
Shortening the barrel is very doable. My first try at it was putting an M4 barrel in an MP5SD5 (it's about an inch to long to stay inside the silencer).
Look at a hardware store/Home Depot type of place for a small diameter pipe cutter (prolly cost you $5). This basically consists of two small sharp wheels attached to a 'C', w/ an adjuster screw to make it tighter/looser.
You put the pipe cutter around the portion of the barrel you want to cut, and just keep turning and tightening it. Eventually it will cut through. Once you cut it off, the tip of your barrel will be too tight to pass a BB (the pipe cutter smashes it in a bit and leaves some extra material there).
I fix this portion by slowly turning an Xacto blade at an angle inside the tip of the barrel to cut away the excess. You want to end up with a bit of an inner chamfer (larger inner diameter at the tip than the rest of the barrel). The brass is pretty soft and cuts relatively easy, although you may go through a few blades. If you have a Dremel with a conical grinding wheel, this might work well too.
Take your time and it will work just fine.

03-16-2004, 11:18 AM
Thanks guys... Good info.

Can anyone confirm Sami's statement that stock barrels have a diam. of 6.08?

03-16-2004, 11:31 AM
I cut mine with a dremel..... then I take an exacto knife and cut around the inner and outer edge of the barrel. The material is soft enough that it cuts it pretty smoothly.

Sami is correct....all of the stock AEG barrels that I have seen today are 6.08mm.