Concave Gas Checks

[jh45gun]

I just started using my 8mm Lee sizer for the first time. The gas checks are coming out concave at the base due to the nose of the bullet behind them pushing them through the sizing die is this normal with Lee Sizing dies and will it hurt anything. They appear to be crimped on tight and look good except for that concave look. Jim

[BCB]

jh45gun,

Are you sure the sizing die is screwed into your press far enough. The bullet should be pushed through the sizing die with a single stroke of the press. You should be able to size one bullet, unscrew the die, and the bullet will fall free when the die is turned upside down. At least that is how mine work. Good-luck...BCB

[felix]

Nothing wrong with concave based boolits. In my personal opinion, they are better than convex types, i.e., boattails. Lead boolits should be always below the speed of sound, or above the speed of sound from muzzle to target. Boattails help condom bullets through this transition. ... felix

[jh45gun]

Thanks BCB that cured it :)