First, no keyhole problems at 50 yards from a 10 22 with 20" barrel.
Second velocity was av 910fps, third, velocity from 2" 34 was av 721fps, 4" 18 was 771 av, and no keyholing from either at 15 yards.
If gelatin is to be used, it needs to have cover--the standard being 4 layers of denim.