Quoted:
MG 124 JHPs and Longshot or HS-6 is the way to go. If you can find it, SP-2 is also a good choice. You can use the different Vhit powders like 3N37/38 or N350/105, but they are expensive and can be hard to find. Thats why I stick with Longshot, in addition to good accuracy and excellent numbers over the chrono.
Seat the bullets long, 1.150 or so and you will be fine.
Medium weight bullets and slow powders are the way to make major.
I am running a 5.5 inch KKM barrel with no holes in a STI 2011 frame. I use both STI and SVI mags.
HS-6 is an old standard and works well if a bit dirty. The BEST 9Major advice will come from the site BrianEnos.com because there are far more people actually loading for it over there.
OP: you did not mention WHAT gun will be used.
If the gun is a SV/STI 2011 (a heavily modified 1911) then the OAL for 9 major is totally different - so long in fact that the ammo you make won't even fit in the magazine or chamber of other 9mm guns.
If the gun is NOT a 2011, then use the max OAL of about 1.160" A long OAL reduces pressure as much as possible and usually feeds better too.
Another critical factor is GOOD BRASS. New is ideal, but expensive. 1x fired is typically used.
ONLY 124 grn bullets win. Forget the 147s - NO ONE who is competitive uses thoes (they will kick like a mule and really slow you down - WAY down - like last place slow).