10MM, 190 gr. and Unique

I discovered 2-3 lb. coffee cans full of 190 grain RFBB bullets I had cast some years ago for my 38-40s, which after some testing, I found neither my carbine nor my Peacemaker clone liked in the least. So, they got shoved back behind a bunch of stuff and forgotten.

Recently I have redeveloped an interest in the 10MM and want to try these bullets in an S&W PERFORMANCE CENTER M&P® 10MM M2.0. I'm not looking to tear a bone out, just a nice comfortable load to shoot on a regular basis so I can use up these bullets. Please don't suggest I try to sell them. I already did with very little success.

In my 610 I use the 175 TCBB bullet and if I have to, I'll use it the 10MM also, but I was hoping, assuming it is feasible and reasonably accurate, to use up the 190s.

Given the powder supply situation I would like to use what I have, Unique. Alliant has gone plumb stupid with their prices but if absolutely necessary, and if I can find it, I would use Blue Dot.

Anyway, my question is: Does anyone here use Unique with the heavier 10MM bullets and what are you results? From what I have been able to find, it seems 6 grs. is a reasonable starting place. Agree, disagree?

I use 6.9 gr Unique with 190 gr swaged bullets in my 10mm. 6 gr would be an excellent place to start.

I used to shoot a lot of USPSA competition with a .40 S&W & a .10mm using a 180 grn bullet. (Until I finally got a .9mm revolver.) I used Unique a lot myself,, and it worked very well. I can't recall the load,, but they are easily looked up in loading manuals.

I originally bought my supply of Unique to reload 10MM with a similar bullet for my then on order Colt 1911 Delta Elite stainless when they first came out in 1987. Colt ended up refunding my money on the DE but I still am using the Unique all these years later.

I agree, start with around 6 grains and see if it feeds OK and cycles the slide. Then fine tune your load for accuracy.

I go a little slower with Power Pistol.

I’ve used it in a GP100 with an Accurate 182-grain ogival wadcutter.

6 grains should be safe.

Based on my testing, my guess is it’ll fall between 850-900 FPS.

Among medium-rate powders, HS-6 has given the best results.