j-frame loading issues?

[dakotasin]

i'm ready to start development for my s&w 636 (i think that's the model number... 38 special +p, 1.87" barrel, da, spurred hammer).

anyway, i was thinking of running 125's, but seems i have heard of light bullet problems in light guns somewhere? so, d'ya think 125's in a hot 38 special loaded j-frame will pose any problems?

 

[WayneConrad]

This weekend I worked up a load for 38 special with a plated, flat-point 125 grain bullet. I fired them through a S&W 60LS, a J frame 357 with a 2" barrel. 6.4 grains of Unique had a respectable feel; 6.8 grains (max load) of Unique hammered my hand a bit more than I liked. The loads I was working up were normal, not +P loads. My load data was from Sierra V.

I don't know of any problems with light bullets, but I'm new at this so that doesn't mean anything. Speer has quite a few warnings about jacketed bullets for 38 special, though. All of Speer's jacketed loads for 38 are "do not reduce" due to worries about sticking bullets in the barrel. Speer gives no 38 special loads for jacketed bullets of more than 125 grains. However, once you get to +P loads, Speer is happy to have you load jacketed bullets of any weight, and provides the usual start & max loads for each bullet.

 

[dakotasin]

yeah, i checked speer 13, and they made no note of bullets pulling thru their crimp, but i could've sworn i read it somewhere credible... maybe i'm imagining it, or just re-living my 480's pull problem or something...

these are to be defensive loads, so i am looking for maximum horsepower out of the diminutive barrel, and going strictly by ballistics numbers, i can get more energy out of 125 hp's than i can 158's...

if the 125 jhp's can't work out, 500 count boxes of cast 158's are inexpensive and will probably work well...

 

[JNewell]

I believe you're remembering the factory advice on bullet weights in the Ti guns. If your gun has a steel cylinder, it doesn't apply as far as I can recall.

 

[WayneConrad]

here is a warning for the AirLite Ti:

When recommending loads for the 342 to your customers, be sure to point out that the barrel of the firearm says, ".38 Special +P Jacketed." S&W's extensive testing showed that lead-bullet +P ammunition has a lighter taper crimp than jacketed-bullet +P amino. A light crimp combined with the rapid recoil of the 342 may cause the bullets in the remaining chambers to unseat from their cases and move forward in the cylinder, causing the gun to jam. Standard velocity .38 Special bullets will not cause this problem.

 

[JNewell]

There was a related caution on the 396 barrel, IIRC, warning not to use bullets over 200 gr. Don't remember if there are similar warnings on the .357M J-frames with Ti cylinders, but I would guess so.

 

[dakotasin]

jnewell - i think you're right. my gun isn't a ti - just a lightweight gun (mostly aluminum, i guess), but it is rated +p, and i would imagine the cylinder is steel.

 

[HankB]

It's not just the crimp, it's how tight the sides of the cartridge case grip the bullet.

Some expanders expand too much - chucking the expander in a drill and using some fine sandpaper to reduce the diameter of the expander by a couple thousandths of an inch can help tighten the grip of the case on the bullet.

Note, you still want the sharp taper intact to very slightly "bell" the case mouth so the bullet can be started in the case.