FWIW,
Those old S&W Model 10s, as well as the J-frame snubbies generally had their sights regulated to shoot to Point Of Aim (POA) with 158 grain bullets.
With handgun bullets, choosing the right bullet weight DOES affect whether the gun shoots high or low. The LIGHTER the bullet, generally the LOWER it hits on the target, and visa versa.
WHICH BULLET WEIGHT?
Well . . . the one that shoots to the bullseye point of aim, of course, at your chosen practice distance! Bullet PLACEMENT is everything!!!!!
BEST LOAD . . .
You'll probably find that this will end up being a 158 grain load that shoots the centers out of a target at ten yards away.
You can't really beat the good old FBI load (158 grain LSWC-HP +P). Remington still makes it and that's what works best in my Model 36 snubbie too.
The other wonderful round in my wheelgun is the 148 grain target load. Yeah, it SHOULD shoot a little lower, BUT the slower velocity means it exits the barrel slightly later, as the barrel begins its rise . . . so both rounds impact just about the same point at ten yards.
Here's a perfect "Point Of Impact" at a target that's only an inch black square . . . shot standing and unsupported at a DISTANCE of TEN YARDS. This is the POA criteria I mentioned is so important . . . much more important than which hollow point load one is carrying.
Your POA results may vary but I'll bet the results will be similar.
+P loads in 158 grain Lead Semi-Wadcutter Hollowpoints will NOT wear out your Model 10 wheelgun for self defense purposes. For practice? Use the light kicking 148 grain Wadcutters.
Heck, for self defense purposes, those obscenely light-kicking 148gn. Wadcutter bullets cut a wicked and large hole as they tear through muscle, bone AND blood vessels. It is actually a pretty decent SD round on its own merit!!!
Ditto on shooting up your roundnose bullets and going for hollowpoints. Although I wouldn't want to be shot by one, I wouldn't want to stake my life on their effectiveness either!
Hope this helps,
T.