Thread: Cracking the Code on another Double Rifle

As you can see from the chamber casts this is a 20 gauge rifle and doesn't have a forcing cone like a shotgun would have.

So despite being 20 gauge the thin brass cases actually take a 16 gauge ball or bullet.

I was unable to find and 20 gauge brass available in NZ
So I committed a crime and decided to use a 577 basic case because it has a bigger rim than Magtech 24 gauge brass

Trim it to 46mm
Anneal it heavily
Put a couple of wraps of tape around the base so the case is centered when the mouth expands during the first firing

70 grains 1 1/2 FG Black Powder
Two hard over powder cards
Force a .650" round ball in with a small Arbour press