Universal Clays, .38Spl, 158gr SWC

[j20owner]

So, runfiverrun sent me a handful of 158gr swc to try out in my dad's gp100 with a 4" barrel. I loaded them with Universal Clays and CCI small pistol primers. According to Hodgdon's data, starting load is 3.5grains and max is 4.5. I loaded 5 each at 3.5 and 4.0 charges. The 3.5 load shot at only 515fps! The 4.0grain load averaged around 587fps. The load data shows these should get 750fps+. Also, there was quite a bit of unburned powder left in the cases and cylinders after firing.

Any ideas?

[GP100man]

yep:
shoot em in a 38spl revolver, in 357 theres more time for pressure to escape around the boolit while it makes the "jump" in the cyl.
try the same load in magnum brass & see what happens.

GP100man

[Kirk Miller]

I may be wrong, but I think you may have used the recipe's for regular CLAYS. Those are the same loads that I used to use for my plinking loads. 4 gr. of PLAIN old CLAYS got me a little over 900 fps. Universal clays is right there with unique in burning speed and applications. Hope this helps.
Kirk

[Kirk Miller]

Oops I did not pay attention that you were using 38 sp. brass. My opologies.
Kirk

[C A Plater]

More crimp may help things. A good roll crimp will hold things in long enough for the powder to a full burn going.

[Kuato]

More crimp may help things. A good roll crimp will hold things in long enough for the powder to a full burn going.

Agreed. I use 4.5 gr Universal in the 38spl with the LEE 158rnfp. Mine drop @ 162gr. I use a good crimp & get nice tight groups off hand at 15 yds. Haven't chronoed the velocities, but I'm dead sure they're going faster than 587 fps. There is a bit of unburnt powder in the cases, but not much..

I've had great success with Universal in 9mm, 38spl, 357Mag & am planning to use it in the 44Mag soon..

[j20owner]

Thanks for the tips. I'm pretty sure I had a good crimp on them. Next time I load some up, I'll snap a few pics to share. My chrono may also have been acting up, so I'll try it again since it's the consensus the data is ok.