Originally Posted by fredj338
Most newbs into shooting & ballistics miss the sectional density part of any caliber. The SD of the 135gr/40 is the same as the SD of a 105gr/357. So if both bullets have the same construction, both penetrate the same. You can drive a 105gr 357sig to 1600fps, so make both a monometal HP & the 357sig wins the penetration & tissue destruction do to the higher vel.
BTW, the 357sig can handle heavier bullets. I can drive the 135grSGDB to almost 1300fps. That is slightly better than a 165gr/40 & going about 100fps faster. It's a shame that Speer doesnt' play w/ this though, it would be a good one, but better than the 125gr @ 1350fps+, probably not. You would get more penetration out of it, but it's already got a good rep for that.
Many newbs also try to use velocity and energy figures alone to decide the effectiveness of a given cartridge.
They forget things like bullet mass (weight) gained in larger bores, and therefore ignore the added momentum and penetration of heavier bullets. They compare the same light weight bullets for both calibers, and fail to recognize the full potential of the larger bore.
If you take a .308 case and neck it down to say, .243 caliber, do you end up with a superior cartridge for big game? The answer is "no". You simply end up with something different, suitable for different needs.
Same concept applies.