ORIGINAL: lemoyne
Semisane
The 200gr Shock Wave.
spaniel
I assume you are talking about the 200gr 40 cal XTP with a BC of .211 as that is correct the correct published BC for the 200 gr SW is .269 my own calculated with a chrony at 2300fps is .260 since I don't know what velocity they calculate them at when they publish them I find it expedient to do my own. Lee
Actually I was referring to the 200gr SW with a BC of .211. I do not bother to calculate BCs myself as all I really care about is the actual drop out of my gun. What I do is take all the real data I can measure, then manipulate the BC in JBM Ballistics calculator until the drops match my actual data. I get something around .21 when I do that. I WISH it was .269, I would get a much flatter trajectory than I actually do.
This is why BCs lead to such arguments, people calculate them different ways and such and it's hard to compare different data sets. If (IF!!!) I get time this spring I want to run the drops on a couple different bullets I haven't tried before including the 300SW. I also need to rig a sabot shield for my chrony so I can verify my velocities again, it has been years since I clocked any ML rounds (dented my buddy's last time despite a sloppily rigged shield!!