I finally got around to running my test rounds for some 357 magnum loads using 2400, new starline brass, Everglades 158gr plated bullets and a mix of half Remington 5-1/2 primers (mag cup w/standard prime)and Federal small pistol magnums(#200) through a chronograph. The results were completely opposite of what I expected...
Across my chosen load spectrum, the Remington 5-1/2s shot faster than the Federal #200s. Many would say that's not unusual, however, the differences were not minor. The Rem 5-1/2s were a good 50 to as much as 90 fps faster. Whether cold bore or warm the results were consistent from 12.2gr up to 13.5 with load levels staggered .5 gr down from 13.5 to 12.5 with the 12.2gr being the starting load.
I shot 10 rounds of each after firing 3 warm up shots with PPU factory 158gr .357 rounds. They averaged around 1100fps through my TRR8. My rounds were batched at the same time, on the same equipment seated and crimped all the same way. I doubted the results so much thinking I had mislabeled them I saved one of each to pull down. My dissection tonight confirmed it.
Not only were these results significant, they were diametrically opposed to what I expected. The greatest nugget within the testing was confirmation that magnum primers are not needed with this powder which has been a long standing belief. It was also interesting to see that even at 13.5 gr, I never got over 1034fps. Obviously no pressure signs throughout that range either.
I even ran a string of a proven 9mm load to confirm proper operation of the chronograph. Also, even though I had some powder flakes regardless of charge, the only group with all 5 shots touching was 12.2gr w/rem primers. I was a bit disappointed to see the groups open up on the SW as it warmed up in addition to loosing fps moving up from 12.2-12.5 grains. Which also occurred with both primers.
I think my next test will be with the 9mm just to confirm that the Federal #200s are possibly the slowest shooting primers I've ever loaded. Anyways, I thought I'd share my little bit of weekend research with y'all and possibly save someone the trouble of trying to make velocity with these primers.
Across my chosen load spectrum, the Remington 5-1/2s shot faster than the Federal #200s. Many would say that's not unusual, however, the differences were not minor. The Rem 5-1/2s were a good 50 to as much as 90 fps faster. Whether cold bore or warm the results were consistent from 12.2gr up to 13.5 with load levels staggered .5 gr down from 13.5 to 12.5 with the 12.2gr being the starting load.
I shot 10 rounds of each after firing 3 warm up shots with PPU factory 158gr .357 rounds. They averaged around 1100fps through my TRR8. My rounds were batched at the same time, on the same equipment seated and crimped all the same way. I doubted the results so much thinking I had mislabeled them I saved one of each to pull down. My dissection tonight confirmed it.
Not only were these results significant, they were diametrically opposed to what I expected. The greatest nugget within the testing was confirmation that magnum primers are not needed with this powder which has been a long standing belief. It was also interesting to see that even at 13.5 gr, I never got over 1034fps. Obviously no pressure signs throughout that range either.
I even ran a string of a proven 9mm load to confirm proper operation of the chronograph. Also, even though I had some powder flakes regardless of charge, the only group with all 5 shots touching was 12.2gr w/rem primers. I was a bit disappointed to see the groups open up on the SW as it warmed up in addition to loosing fps moving up from 12.2-12.5 grains. Which also occurred with both primers.
I think my next test will be with the 9mm just to confirm that the Federal #200s are possibly the slowest shooting primers I've ever loaded. Anyways, I thought I'd share my little bit of weekend research with y'all and possibly save someone the trouble of trying to make velocity with these primers.