What did you use to drill it?
21/64 metal bit on a drill press, 1/8 NPT (27 thread) tap. The leak is about an inch away on either side from the tapped fitting.What did you use to drill it?
Yes, that diagram looks very close to it. This could be the issue, but I'm unsure why the front bottom would also leak. I will try this.Simply apply a car gasket maker (I used this : http://www.p-wholesale.com/upimg/15/58a2/gasket-maker-red-et5005-196.jpg) between back plate and magazine body and the problem should be gone.
PS: and yes, there is an O-ring, one could put it into silicone, but it helped only temporary.
There doesn't appear to be any cracks. I drilled at moderate speed, so I doubt it was too fast? I'll try the gasket maker and give an update.Sorry, I haven't checked in a little while...
How fast was the drill spinning?
If it was too slow, you could have put too much pressure on the mag itself and cracked it, or if it was too fast, it could have stressed the metal through heat. You really need to do it at extremely high speed with cutting fluid.