Using the info on the PT boat site, I attempted a 1:12; I don't have all the drill bits I need to finish all, but should be able to make some progress. This was practice for 1:24, and the 1:12 experience makes me re-consider trying for the half-scale for my sub model.
Here is the basic start:
barrel is 3/32 (bore is 1/16, or .063, this is about as close as one can come with K&S tubing.), 1/8 spacer, and 5/32 perforated barrel sleeve. I ran short of 1/8 (only had about 3/4" left!) so will have to correct the aft-end tube later (too short, I didn't have enough tube left). The receiver is cherry, but I goofed on cutting the relief on the bottom. If I go ahead with the half-scale, I will probably use rectangular brass tube for the receiver.
Here is close in on the barrel; I don't have precision equipment, so my drill-guide was off.
This was basically an experiment, but I'll probably finish it up with the handles and a mount, and a magazine (from Destination Tokyo). I'll see how I feel about it when it comes time to try to make the smaller scale.
regards, John