20 GAUGE FROM HELL???

[IOWA DON]

Here are my Thompson-Center TCR's with custom 20-gauge fully rifled barrels. Outside barrel contour is the same as the factory 10-gauge mag barrels so there is a lot more wall thickness. They would probably stand 20,000 psi loads if one could stand the recoil in such light guns. I normally shoot deer with sabot slugs, but cast lead slugs for plinking. They weigh 720 grains or 540 grains hollow-pointed. I shoot the 720-grainers at 1,000 fps and the 540-gr hollow points at 1,200 fps. Both loads are fairly accurate.

[Graybeard]

They would probably stand 20,000 psi loads if one could stand the recoil in such light guns.

Yes the gun very well might but the shotshell case is NOT made for such pressures and almost assuredly would not. Do you really want to pull the trigger and have the case spill all that pressure out? The rifle has no real system in place to properly vent gases in a case rupture.

[IOWA DON]

GREYBEARD - The cases were made by Rocky Mountain Cartridge from a chamber cast of the gun. The guy there says they are good for 20,000 psi. Per conversations with AA Powder Company it appears my 720-grain slug at 1,000 fps is no more than a 12,00 psi load. By the looks of the primers it is considerably less than factory 20-gauge shells. Anyway, I think the guns and brass will take a lot more than my mild loads. They are fun to shoot though. A 720-grain slug at any velocity has a lot of momentum and kicks up a lot of dirt. I will post another Big Bore topic on the .50-140. - DON