You cannot compare the penetration of those two rounds because they are completely different rounds and even a cursory look at the pictures shows that the 180gr Ranger loads had more robust and consistent expansion through denim. In fact it appears that the 155gr silvertips probably went out the other side of the gel block because they did not expand at all. This is a much more likely and logically sound explanation than the one you presented. If you shoot a winchester white box 165gr FMJ into gel it will probably go out the other side, if you shoot a Ranger T 165gr JHP into gel it probably won't simply because it expanded. Look at the picture of the 155gr silvertips. The one bullet that they were able to recover through denim appears to have little expansion. In fact probably the only reason it stopped in the gel was because it shed it's jacket.mcb said:The Winchester 155 grain load with 400ft-lbs of energy average 12 inches of bare gelitane and 4 of 5 got over 18+ inches of penetration in denim covered gelatin. The 180 grain load that had 327ft-lbs (18.25% less) had 11.2 inches of penetration on bare gelatin and with the denim in place averaged only 13 inches.
Of course. My whole point is based on comparing the same bullet and caliber just in two different weights. Looking back I probably didn't make that clear. Sorry about that. I agree with you that there are more things to take into account than weight. However, you can usually say with pretty good accuracy that a slightly heavier loading of the the same round will penetrate a bit more than the lighter load.mcb said:Fair enough I did compare apples to oranges but weight alone is not enough. For example I don't think you would expect a 180 grain bullet from a 40S&W to out perform the same bullet design in say a 165 grain version fired from a 10mm, assuming both were load to max pressure. Or say a 240 grain bullet fired in a 44 Magnum compared to the same bullet design in 180 grain fired from a 444 Marlin if both were loaded to max pressure. Sufficient kinetic energy will allow a lighter bullet to out penetrate the heavier bullet of the same design (assuming the lighter bullet can maintain integrity). Weight of the projectile alone is not enough info just as kinetic energy or momentum alone is not enough info.