Which One?
Good Question.
On Dale Towert's Stopping Power Page, there's an interesting comparision.
http://www.evanmarshall.com/towert/penetration.htm
In inches of plywood, here's the results;
(.357 magnum)
158 gr SWC 4.0"
145 gr silvertip 3.0"
125 gr SJHP 2.5"
--158 gr JHP 2.2"--
110 gr JHP 1.8"
(for comparision, .38 special)
158 gr SWC 2.3"
125 gr JHP +P 1.7"
110 gr JHP +P 1.4"
158 gr SWC-HP +P 1.3"
Keep in mind two things. A heavy object and a lighter object moving at the same speed, the heavier object will have the more kenetic energy when it impacts something. The trouble with this is that we have no idea what the relative speed of the objects are. Typically, one can make the lighter weight bullets tavel faster, and some times a lot faster! For instance, if you load a .357 110 grain JHP with Alliant's Blue Dot powder, you can make the bullet go over 2,000 fps with 33,800 psi for the barrel . On the otherhand, using 2400 powder, one can make a 300 gr LSWC go 1,600+ at 34,000 psi. How fast were the bullet's taveling? Would a 110 grain bullet flying at 2,000 fps penatrate farther than a LSWC traveling at 1,000 fps? Which brings me to my second point.
Bullet Design. Notice how the 158 gr SWC went 4.0" in and the 158 gr JHP only went in 2.2"? Does this strike anyone else as a curious thing? Obviously a JHP bullet is designed to open up and expand and thus loses energy. For self defence work, you want a bullet that does not over penetrate (ei- bullet go through the bad guy, hit's good guy or girl behind bad guy!). So if you want something that penetrates, stick with FMJ or hardcast lead. But if you want a self defence round, pick a hollow point bullet.
Hope this helps!