Hi all, I picked up a stick of 1/2" brass round bar today for makeing some 470 bullets. The one I made for my proof load had about 50% of the shank reduced to relive pressure, but it was suggested that smaller bands might work better. I had a thought about a more uniform way to turn grooves on my manual lathe.
What if I turned threads at say 10tpi on the shank, then cut a nose on the end. It would probably look strange, but seems like it would work just the same as turning individual grooves. What about an acme style thread instead? What depth would work?
Thoughts?

Lar45,
Sounds like a good idea. If you make the threads turn in the same direction as the rifling, they would probably improve the spin of the bullet a bit. How much I dunno. If the thread direction was opposite the rifling twist, it might be detrimental to imparting spin to the bullet. How much I dunno. Sure would be a quick way to mass produce some uniform projectiles with out the CNC.

I'm impressed with your homemade double rifle. Strong work! Some homemade bullets, great! What will you call them?

Screw Bullets?

There are different kinds of brass. For bullets use only 72% copper brass. Lower content of copper, which is usually taken for hardware, will ruin the barrel.
Grooves are best, if their depth are the same as the depth of the rifling.