Firearm - Bolt action inline muzzleloader with 24" barrel length Cartridge - Barnes Spit-Fire TMZ copper hollowpoint, 50 caliber sabot with 290gr 0.456" sub-projectile. Item # 45190. Propellant charge was 100gr of Hodgdon Triple Seven (2 pellets), with 209 primer. Block calibration - 12.0cm @ 607 ft/sec Distance between muzzle and the face of the gelatin block was 10 yards. Chronograph malfunction produced a reading of '341' ft/sec for the impact velocity. Shot penetrated 20.7" (corrected) and expanded to 0.711". Please note that the corrected penetration depth was calculated as follows : Using Fig. 10-10 and Fig. 5-2 in Bullet Penetration and knowing that both the primary block and the stopper block had almost exactly the same viscosity, a linear interpolation was made, as the deepest represented penetration depth (X) was 18" on Fig. 10-10, and a figure of (26.5"-5.8") = 20.7" was arrived at for the corrected penetration.