.40 Major Loads for M&P

[Spiff]

Hey folks -

I've been digging around the internets for a while now looking for good info on N320 and 180gr moly stuff for major .40, but haven't found a really clear answer. Particularly for a short OAL gun like an M&P or a Glock. Has anyone used this particular combo?

There's a lot of data for jacketed bullets, but not much for moly. I've never loaded moly, so what is the general rule for it compared to jacketed? Do you back the loads off a little?

I'm definitely planning on starting off light and going up from there.

 

[irons_shooter]

Yes.. In-fact Sean McCanne currently shoots that same combination (sub 320 with WST which is almost identical). If I am not mistaken he is using 4.5gr at 1.135 with a 180 BBI.. I used 4.7gr with this load at 1.175 for my s_i.

 

[Spiff]

Cool, thanks man! Hopefully I'll be able to chrono a bunch of different charges before long.

 

[Craig Westerman]

With the Black Bullets International (Poly-M) bullet, 4.5 gr makes major in warmer weather. I have to bump up to 4.6 grains when it cools down. See attached Excel file showing chrono results through 4 different barrels (factory G22, 2 G22 Barsto and a factory G35). Also shows FMJ for comparison.

 

[Spiff]

Whoa! That's great stuff! Thanks man!