700 Nitro Express Power From a 12 Gauge Shotgun

1100 grain cast bullets at 2400 fps? From a 12 gauge shotgun?

Yes, it’s true. Actually a slightly modified shotgun…3.5″ chamber and a heavy barrel but you can get a 1100 grain bullet to go 1700 fps from a H&R Ultra Slug Hunter gun with just a lengthened chamber.

….meet the 12 Gauge From Hell.

12 gauge from hell

The top cartridge is the 3.5″ 20 gauge from hell (RMC Case). The 2nd cartridge is the Rocky Mountain Cartridge (RMC)12 gauge 3.5″ brass case. The 3rd is the 3.85″ 12 gauge case but made from a 50 BMG case. The 4th is the RMC 3.85″ 12 gauge from hell.

So how is this (1100 grain bullet at 1700+ fps) possible?

Use a brass case and lots of slow burning powder (H50BMG) to keep pressures low. You can buy brass shotgun cases from a few different manufacturers but Rocky Mountain Cartridge is the best known. The cases are expensive but they last forever.

Load data is available at a few gun forums such as the Accurate Reloading Forum. You can read the entire thread. It’s interesting as hell.

It is really amazing how much power you can get out of a 20 or 12 gauge shotgun with low pressures. You do not have to spend thousands of dollars for a big bore rifle. 600 Nitro and 700 Nitro rifles are $25K and up. For a few hundred dollars you can get the same power.