PM9 chrono results...

[alank2]

Hi Everyone,

I didn't have factory ammo today to make the comparison, but I did shoot the same loads in two guns to compare. PM9 vs Glock 19.

The Glock barrel is 4.02" while the PM9 barrel is 3.08" barrel. Both barrels are polygonal.

.355 Zero JHP 115gr, VihtaVuori n330 5.1gr, SP CCI 500, 1.130 oal

Kahr PM9
Velocities : 1059, 1040, 1038, 1070, 1063, 1042, 1037, 1053, 984, 1024
AVG=1041 fps, ES 86, SD 24
(If the low 984 is thrown out, AVG=1047 fps, ES 46, SD 14)

Glock 19
Velocities : 1132, 1143, 1169, 1159, 1151, 1152, 1148, 1152, 1148, 1158
AVG=1151 fps, ES 37, SD 9

The PM9 only lost 9.6% average velocity despite its 23.4% shorter barrel.

The other load I tested was probably on the long side for 9mm, but it shot successfully:

Starline Nickel (New), .355 Speer GDHP 147gr, VihtaVuori n330 4.3gr, SP CCI 500, 1.142 oal

PM9
Velocities : 884, 898, 896, 910, 895, 897, 882, 897, 897, 909
AVG=896 fps, ES 28, SD 8

Glock 19
Velocities : 960, 957, 967, 964, 953, 968, 985, 979, 969, 976
AVG=967 fps, ES 32, SD 10

The PM9 only lost 7.3% average velocity despite its 23.4% shorter barrel.

Needless to say, I was very pleased with a very small 7.3% loss. I plan to push this 9mm defensive load a little higher, perhaps 20-30 fps to see how it does.

Thanks,

Alan

[f44life]

very interesting, so you can still pack about the same punch with the shorter barrell

[alank2]

Hi,

I was impressed. I really thought going from 4" to 3" would have a bigger performance penalty than it did.

Thanks,

Alan

[joshh]

sweet post. i carry the 147gr in my pm9 for defensive round. i would have thought the dropoff would have been greater.

[4T5Guy]

That's great. I have wanted to do kinda the same chrono tests, but haven't yet. I want to see velocity a bit farther out, I assume your data is from a few feet away from the muzzle? My plan is to throw the same rounds from all of my 9mm's at 10ft and 20ft. My PM is the only one that has polyrifling, but that really is not my interest. A member of this forum stated that a laser was not needed on a PM9, due to some 10ft defensive distance. I want to see what the velocity is at farther distances, to figure out how much energy is lost with such a short barrel. With both of my PM's I am shooting 2" sub's at 25', and knocking down the steel at 50' & 75', but with how much energy? I'll post the results, if I don't hit my "screens" !! Chrome compared to a laser, WHAT???, just sit down.

[Tilos]

alank2:
Thanks for posting this info
Just sayin'
Tilos

[DKD]

Interesting post. I didn't expect the outcome to be different though. Please also keep in mind with hand loads we can taylor the burn rate of the powder as well as the bullet weight to increase short barrel performance. Faster burning powders do well in short barrels especially with heavier bullets. Normally the heavier bullets in a given calibre perform better with medium burn rate powders which generally work best with a slightly longer barrel....so this test didn't really mirror the rule of thumb in this instance.
Manufactures only worry about uniform SAMMI pressures with a given powder lot and use many different powder sources at times due to their bulk manufacturing process.

[arizona98tj]

Another example of the same load being used in two different pistols, my PM9 and my XD9 4". This was a load of Unique pushing a Berry's Mfg 115gr RN TMJ. The chrono was right at 10' from the muzzle, which is my standard distance.

5 shots average 1017fps 20.4SD PM9
5 shots average 1152fps 24.1SD XD9