5of7 said:
This talk of shotgun slugs for defense against Grizzly bears prompted me to calculate the SD of a 12 ga. shotgun shug.
I found out that even a 1-1/2 oz 12 ga slug has a SD of .176....essentially the same as a 158 grain .357 diameter bullet.
The more common 1 oz slugs come out at .117, about the same as a 40 grain 22 long rifle bullet.
Why would anyone think that a 12 ga. slug would offer up enough penetration to reach the vitals of a griz?
I've been trying to figure this out myself. Shotgun slugs have a pitiful sectional density. Even the massive Dixie Terminator slugs have an SD only equal to a 250gr .44 bullet. Yet for whatever reason, people have this silly perception that shotgun slugs are the hammer of Thor and destroy all in their path. Regardless of what we 'know' about big bores, heavy bullets and terminal ballistics. I'm determined to prove it as pure myth.
I came up with a ballistics chart in the form of an Excel spreadsheet and it's very interesting how slugs compare to big bore revolvers and 'real' stopping cartridges. Not favorably. Here's an excerpt:
Cartridge/Load/ Dia./ Wt./ SD
12ga 1oz Foster 0.730 438 0.117
12ga 1 1/8oz 0.730 492 0.132
12ga 1 3/8" Brenneke 0.730 602 0.161
12ga Dixie Terminator 730gr 0.730 730 0.196
12ga Dixie Terminator 870gr 0.730 870 0.233
.44Mag 0.430 330 0.255
.44Mag 0.430 355 0.274
.45Colt 0.452 335 0.234
.45Colt 0.452 360 0.252
.475/.480 0.476 355 0.224
.475/.480 0.476 400 0.252
.475/.480 0.476 430 0.271
.500 Linebaugh 0.512 435 0.237
.500 Linebaugh 0.512 450 0.245
.500 Linebaugh 0.512 500 0.272
.375H&H 0.375 300 0.305
.444Marlin 0.430 405 0.313
.405WCF / .450-.400 0.411 400 0.338
.45/70 0.458 405 0.276
.45/70 0.458 500 0.341
.45/70 0.458 540 0.368