Tatume
06-24-2013, 01:58 PM
Hello Folks,
Although I’ve owned an S&W M39 for many years I’ve never loaded for it, and really only kept it for sentimental reasons. In the late eighties I owned an H&K P7M8 but never loaded for it either, and later sold it (a decision I regretted). This week I had an opportunity to purchase an H&K P7 (aka PSP) and snapped it up. I had on hand FC 115 gr HP, R-P 115 gr FMJ, and was given a box of PMC 115 gr FMJ with the gun.
Then I went looking for components. None were to be found except CCI small pistol primers, of which I was able to get 2000. Fortunately, I was able to trade components on the S&S forum here, and acquired sufficient brass and bullets to last a long time. I had a set of dies that came with the M39.
Having no experience loading this cartridge, I decided to shoot and measure some of my factory ammo, and use the Ken Waters method for load development. All fired case diameters were measured in inches with a vernier micrometer, and measurements were made at the “expansion ring” just above the solid head.
PMC ammo had the smallest expanded diameter, with an average of 0.3912. Average velocity at 15 feet was 1044 fps. R-P average fired diameter was 0.3927 with 1026 fps average velocity. FC average fired diameter was 0.3928 and average velocity was 1097 fps.
Based on these measurements I (somewhat arbitrarily) considered 0.3925 to be the maximum acceptable expansion in the P7. My first set of reloads with 115 gr X-Treme plated bullets and mil surp M9 powder (similar in burn rate to Unique, a little bit faster) gave an average measurement of 0.3917 at the expansion ring, and average velocity was 1098 fps. OAL was set to a length that worked through the magazine; I didn’t measure it. Reliability with all ammo has been perfect in the P7, which is to be expected. Accuracy of the reloads was equal to the factory ammo, any of which will easily clean the falling plates at 25 yards. I find this to be entirely satisfactory.
Thank you.
Take care, Tom
Although I’ve owned an S&W M39 for many years I’ve never loaded for it, and really only kept it for sentimental reasons. In the late eighties I owned an H&K P7M8 but never loaded for it either, and later sold it (a decision I regretted). This week I had an opportunity to purchase an H&K P7 (aka PSP) and snapped it up. I had on hand FC 115 gr HP, R-P 115 gr FMJ, and was given a box of PMC 115 gr FMJ with the gun.
Then I went looking for components. None were to be found except CCI small pistol primers, of which I was able to get 2000. Fortunately, I was able to trade components on the S&S forum here, and acquired sufficient brass and bullets to last a long time. I had a set of dies that came with the M39.
Having no experience loading this cartridge, I decided to shoot and measure some of my factory ammo, and use the Ken Waters method for load development. All fired case diameters were measured in inches with a vernier micrometer, and measurements were made at the “expansion ring” just above the solid head.
PMC ammo had the smallest expanded diameter, with an average of 0.3912. Average velocity at 15 feet was 1044 fps. R-P average fired diameter was 0.3927 with 1026 fps average velocity. FC average fired diameter was 0.3928 and average velocity was 1097 fps.
Based on these measurements I (somewhat arbitrarily) considered 0.3925 to be the maximum acceptable expansion in the P7. My first set of reloads with 115 gr X-Treme plated bullets and mil surp M9 powder (similar in burn rate to Unique, a little bit faster) gave an average measurement of 0.3917 at the expansion ring, and average velocity was 1098 fps. OAL was set to a length that worked through the magazine; I didn’t measure it. Reliability with all ammo has been perfect in the P7, which is to be expected. Accuracy of the reloads was equal to the factory ammo, any of which will easily clean the falling plates at 25 yards. I find this to be entirely satisfactory.
Thank you.
Take care, Tom