I have had this on my to do list for awhile but didn't know how to go about making some 50 cal. machine gun so I did some research and like always the net has taught me another technique that I thought I would share. I'm sure this has been posted before but though it might be helpful for someone like me that has not come across the tread yet, any way it fairly simple. I didn't like the off the shelf guns so I thought it was going to be a simple matter of just drilling some holes in brass tube and I would be done, the problem I had was getting six rows of holes straight and even After I spent some time on the internet I found how its done, the picture show a tool that I made from an old aluminum turn buckle, using the flat areas to center off from I found that this tool made the job very easy and quick. I then took a brass washer and turned it down to fit inside the cooling tube, then fit the polished smaller aluminum tube to the inside of the washer. I also made the guns removable so that when transporting the plane the guns don’t get damaged, this was a method I used on another plane it works great.

Ron