Grand Power K100/GP6 Reloading Questions

[Okami]

I started dabbling with Production late last season after picking up a Mk7 on a pretty sweet deal. This year I'm wanting to play with Production more than my usual Limited, so I went ahead and added the 9mm to my loading setup. The kicker is that I'm setting up a load that will work in three different guns; K100 and MP9 Pro 5" mainly with a CZ P-01 for fun/back up gun.

I'm aiming for 130-135PF but what I finding interesting is the results with the K100. Namely that is seems to lag behind in the higher range by a decent amount compared to the M&P and even the CZ. For some reason its just not building the speed like the others.

Have others noticed anything similar? What loads are you using or tried with your K100/GP6?

Here's what I've recorded so far. Just going for ball park before fine tuning so all numbers are the average of what was seen

Powder: Titegroup
Bullet: Xtreme 124gn FP
OAL: 1.053
Primer: WSP

PWDR VEL PF PWDR VEL PF PWDR VEL PF PWDR VEL PF PWDR VEL PF PWDR VEL PF
P-01 3.80" 3.4 894.5 110.918 3.6 963.75 119.505 3.8 996.00 123.504 4 1037.2 128.613 4.2 1070.0 132.680 4.4 1089 135.036
K100 4.25" 3.4 914.4 113.386 3.6 947.4 117.478 3.8 1004.6 124.570 4 1021.4 126.653 4.2 1043.0 129.332 4.4 1074.7 133.259
M&P9 5.00" 3.4 942.6 116.882 3.6 981.8 121.743 3.8 1052.2 130.473 4 1076.2 133.449 4.2 1101.7 137.599 4.4 1148 142.352

With the growing popularity of the GP line, I thought this would be a good topic to get rolling since I haven't seen much information in the way of loading for the platform.

EDIT: updated load data for which gun

Edited March 1, 2015 by Okami

[zhunter]

Shorter barrel produces lower velocities.

[Canuck223]

I use 3.6gr VV N320 and Zero 147gr JHP's or 4.2gr VV N320 and Zero 125gr JHP-C.

[Okami]

Shorter barrel produces lower velocities.

Made me realize that I had not labeled which gun for each string. Thanks for that. Whats interesting is that the 3.8" CZ is producing higher velocities than the 4.25" K100 as you move into the hotter loads.

I use 3.6gr VV N320 and Zero 147gr JHP's or 4.2gr VV N320 and Zero 125gr JHP-C.

I'm assuming this is tuned for the Xcalibur? Do you use the same loads for your other GP? What numbers are you seeing?

[Canuck223]

For the 147's, I aim for 900fps and the lowest 10 shots of 50 to be at least 875.

I do load for the X-Calibur, but developed the load with my Mk6 GP6. It's been consistent in both of my X-Cals.

[NicVerAZ]

My load is 3.3gr of Titegroup with 135gr Bayou bullets, OAL 1.120"

Works perfectly and very accurate, with a consistent PF of 128.

You may bump the powder by 0.1gr for a safer PF, or play with a shorter OAL. I also suspect Titegroup to be temperature sensitive.

NOT a fan of 147gr bullets. Not enough kinetic energy to flip big poppers consistently.

I also think you load too short. This is not a CZ. A bit more OAL is nice.

Edited March 10, 2015 by NicVerAZ