Bearing Barrel

[Lockednloaded]

I'm working on full auto, so I decided to get a more precise ammo than marbles. I would like to use either 1/2" or 3/8" bearings because they are the cheapest, but I'm having the hardest time finding pipe with an ID of 1/2" or 3/8". Anyone got any suggestions for the barrel/magazine material? note that it has to fit together with standard pipe fittings

[saefroch]

3/8" NPT pipe has an ID of .495" with a small lip on either side. Grind out the lip, and 1/2" ball bearings should fit pretty close. If it's too small, you can machine something that's a very tight fit and just wear down the inside to shave off .005".

[Lockednloaded]

I have a .5" drill bit, but its about 4" long, so that probably won't do...

PS, could an air ram keep up with full auto?

[saefroch]

A .5" drill bit will usually drill a hole wider than .5" because of the precession of the drill. I'd use the drill bit and just push it back and forth through the pipe once you remove the lips on the ends.

[Lockednloaded]

just as a test, I just drilled a hole in a piece of HDPE, it fit the bearing perfectly, but it gave me another idea: I use 8705K331 (.5" ID HDPE tube) and hand machine a loading block with 8671K49 (Block of HDPE) The stuff is so easy to machine that I could do it with a hand drill. anyone with experience boring holes, do spade bits work well?

[POLAND_SPUD]

I'm having the hardest time finding pipe with an ID of 1/2" or 3/8". Anyone got any suggestions for the barrel/magazine material? note that it has to fit together with standard pipe fittings

get either 10mm aluminium or 13mmID copper barrel

[Lockednloaded]

I can't get either on mcmaster , BTW POLAND_SPUD, IIRC, you mad a 3D diagram for your loading block, can I get a link to that? and also aimed at you, would an air cylinder work with a QEV+Pop-Off design?

[POLAND_SPUD]

nope it won't work

[Lockednloaded]

Thanks POLAND_SPUD, I'll probably work with the detent or try a blowback kind of thing