9mm major load question

[44stevenson]

I've currently reloading 147 grain bullets with 3.0 grains of Universal at 1.150 OAL and currently avergaing about 980fps.

So if I need to get to 1122 with a 147grn bullet to get to major power factor then i should be able to reach major pretty easy. in my research before dropping .3 of a grain of powder usually yielded about 100fps with Universal powder. So by that math I'm assuming I can make major with 3.6 grains of Universal powder.

I always see people saying that its unsafe to make major power factor in a gun like the M&P, but I think most are just running their mouths about something they know nothing about. I don't understand how it would be unsafe as its around the same fps as factory loads. I've also seen other people online making major in m&p's, and I do have a sotrm lake barrel in my gun.

Thoughts???

[mlmiller1]

It is very risky assuming linear velocity gains with powder increases. What can happen is you will stay linear for a ways but then suddenly you will either flatten out--no gain in velocity for more powder, or you will jump up velocity wise dramatically for small powder increases. Both of these are danger signs, both may show up too late & you can potentially blow brass or worse. Be very very careful with low powder charge powders like Universal. It doesn't take much error at all to have a big problem on your hands. Some type of powder that has more volume, aka "slower powder", is much better for developing major power loads.

Unless you are shooting in Open division in uspsa or IPSC, major power factor out of a 9mm gun is a waste of components & stress on your weapon. Even shooting major loads, unless you are in open, you will be scored minor with the 9mm caliber. If by chance you aren't shooting uspsa or ipsc Open, why do you want major power factor loads? Last time I checked, by the way, there were only a couple of foreign brand ammo manufacturers building ammo for machine guns that made major power factor. No other manufacturer, especially of the common brands normally available off the shelf will sell loads that hot.

Be very careful with any "assumptions" when you go way beyond book loads. You blow up that hand cannon, shrapnel launcher, you hurt yourself or someone else it will be YOUR fault!

[44stevenson]

I am asking this for the purposes of USPSA open. Book says that 3.6 grns of universal with a 147grn bullet is fine, that is the max charge in my book.

[EkuJustice]

For open give up both the powder and the bullets Nd everything you know about production loads and start from scratch. For production heavy bullets And small amounts of fast burning usually work best. For open you need large amounts of slow powder and light bullets. The slow powder and Lot of it give you gas for the computer. More gas is better. Also you won't find 9 major loads in the book do you have to work up a d look for pressure signs. Autocomp and hs 6 Are good powders to use in the shorter open rounds which I would go 1.145 min and 1.155 is better. Also stick with cmj or Jhp bullets as plated lead and fmj don't work we'll at major. For autocomp a Montana gold 124 grain cmj with 6.8-7.1 will be the range most use at 1.15 but go low and work up

[DRobson]

The only published load data for 9major would be with 3n38 and a 147gr FMJ/JHP. I tried this combo in a heavy 9mm EDGE and it was stout. Not sure why you'd want to load 9major in a M&P unless it's setup for open.

[Guest]

^^^^

...The slow powder and Lot of it give you gas for the computer. More gas is better...

Well, i guess it was bound to happen sooner or later. Computerized open guns. Great... >>sigh<<

Edited May 18, 2013 by Bamboo

[superdude]

Yes, if you're running a compensator, you're better off with light bullets and large charges of slow gunpowder. You can check out the relationship between gunpowder and recoil here:

http://38super.net/Pages/Gunpowder%20and%20Recoil.html