Tuesday, August 11, 2015

My son is looking for the best 9mm load in a carbine/submachine gun length barrel.

I will soon have in my hands a folding stock PPS carbine converted to 9mm NATO that I intend to gift to my son when he returns from Germany. Consequently I'm looking for some handloaders experienced with loading heavier 9mm rounds (124 grain, 147 grain) for optimum performance in a 16" barrel 9mm carbine/submachine gun. Lighter loads (115 grain) may not reliably cycle the PPS action, and if there's one thing necessary in such a platform it's reliability. I'm thinking of this as a vehicle carry piece, capable of engaging assailants in other vehicles, so I need maximum throw weight, penetration and velocity. Too bad they don't sell new or salvaged steel core projectiles anymore.
I'm looking for load data because to buy the complete rounds new would, I'm assuming, be prohibitively expensive and if there's one thing I'm low on at the moment it's ammo money. A faithful reader the other day sent me unsolicited 2000 pieces of 9mm brass, so I'd like to come up with a good load for that PPS 9mm NATO carbine (one of the project firearms that Len Savage is building). Anyone have any informed ideas about such a load optimized for the platform?
When finished it will look something like this:


Anonymous said...

My Erfurt P08 gags on anything commercially available. So I feed it a supposedly +P handload consisting of a Montana Gold 124 grain bullet over 4.3 grains of W231. The manuals suggest a max load of 4.5 grains but 4.3 cycles this old piece as well as 4.5 and I didn't see any need to beat up a 100 year old pistol.

If I was developing the load you're looking for I would think something between 4.3 and 4.5 grns of W231 would do the trick.

Anonymous said...

Did you consider 147 gr. bullets? They provide a long duration of back pressure to function the action with longer barrel dwell time.

Anonymous said...

Mike, check the Ballistics by the Inch website, or contact Kel-Tec, they probably have some data since they have been selling 9mm carbines for quite a while. Last resort of course is to find a reloading manual - I hear you are pretty good at scrounging such items ;-)

jfre said...

147 grain Berry's plated bullets over 3.4gr of Clay's Universal. Nice subsonic load for blowback operated subguns like the Uzi or MAC

Anonymous said...

You're going to have higher c.u.p. because of the longer barrel plus high muzzle velocity. I'm betting that the 115 grain will cycle the action just fine and keep the kick down. My experience is with a Marlin Camp 9 carbine. Never considered changing the load. Shoot pretty good with regular pistol loads.

Anonymous said...

Commercial offering from Buffalo Bore

Flash-suppressed from a carbine should be almost without flash in the dark.
Compare to M44 shortened with 180 grain Bulgy silver tip (cartridge-based flame-thrower with projectile launching).
No search results for carbine-optimized 9x19mm (longer-pressure with standard peak, that would make an excellent flame from a handgun). This sounds like a job for a custom-load. Tungsten solids, with a copper jacket? :-)


Anonymous said...

Don't overthink it. That thing is a truck. Buy several commercial loads, and try them in onesies and twosies until you find one or more that feel right and will hold the bolt open on the last round, provided the faux-43 holds open. Copy your favorite load. My MP-35 eats everything from slow 115-ers to whanging 147s, the only thing that changes is how fast she cycles.

Anonymous said...

I have limited experience with 9mm; but I've worked thru this issue with .38 special & .357 magnum, in 2" & 6" revolvers to 16"-18" carbines. The traditional, slower magnum powders tend to yield greater velocity (> 200 fps) in the carbines, but finding load data for the smaller case capacity of the 9mm may be tough.
With that in mind, I do have a 9mm load worth trying. I used a Lee mold, 9mm LRN, listed as 124 grain, but mine run about 128g. Lubed with liquid Alox. I loaded these over 8.0 grains of Blue Dot. In my Ruger P series, these chronographed about 1,225 fps, spread less than 50 fps, and no leading. YMMV


Anonymous said...

After thinking about it at length, you should find the ammo that is the most plentiful on the market. In a 4GW situation, you will likely have to use whatever you can get, which would either be standard, run of the mill commercial ammo, or standard commercial import ammo. Instead of tweaking the load, tweak the mechanism/spring to insure it cycles right.

What you don't want is highly customized ammo requiring hand loading. Make it work with regular stuff.

You will probably find all this speculation moot as it will work fine with store bought ammo.