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testing results will be posted
bpost
Member Posts: 32,669 ✭✭✭✭
As weather permits I will post the results of testing with pistol and some rifle loads comparing the MV between magnum and standard primers. I will also include any differences I can find in case head expansion, primer appearance and case length growth.
I loaded some test rounds this evening in 8MM Mauser, 15 each with mag primers and 15 each with std primers. The loads used were Unique and IMR 4198 with a gas checked cast lead bullet. If the rains stay away tomorrow I will get the chronograph out and see what real world difference we can see.
I will also test the same primer comparison in the 45ACP, 357 mag and 44 mag. Those results will be posted as I can get the tests completed.
Hope it helps build understanding in the real world results are when comparing the standard vs mag primer.
I loaded some test rounds this evening in 8MM Mauser, 15 each with mag primers and 15 each with std primers. The loads used were Unique and IMR 4198 with a gas checked cast lead bullet. If the rains stay away tomorrow I will get the chronograph out and see what real world difference we can see.
I will also test the same primer comparison in the 45ACP, 357 mag and 44 mag. Those results will be posted as I can get the tests completed.
Hope it helps build understanding in the real world results are when comparing the standard vs mag primer.
Comments
Reloading for pistols is new to me and you may save me some time (maybe money, too) with the .45 portion of your testing.
The Lyman Cast Bullet handbook had an asterisk beside a load of 27 Grains of IMR-4198 as potentially the most accurate load. The book claimed 1925 FPS from a 323470 160 grain bullet. I am using a Lee 90274 (C324-175-R) instead.
I loaded reformed 30-06 brass with Federal magnum primers and a load of 27.0 grains of IMR-4198. The book claimed 1925 FPS, I got 1920 average with a 48.4 ES and a SD of 14.03. That is not too bad for a old military rifle.
Today I was able to test the standard primer loads over the chronograph. The results I got were astounding to me and quite unexplainable.
The same load as above, EXCEPT for the primer. This test used a standard primer. The primer used was Remington. This load produced an average velocity of 1977 FPS with a ES of 44.8 and a SD of 14.17. How on earth a standard primer could result in a higher MV than the mag primers is no computing to me.
The big difference in the testing was the full sun was out today and my previous test was on a cloudy day. Could differences in the chronograph from sunny to cloudy cause misreadings?
This load proved to be every bit as accurate on paper as before.
Time ran out for more extensive testing with the N133 loads but the five shots across the chronograph gave 1992, 2057, 2036, 2096 and 2026 FPS. That load was 31.5 grains. At that speed I am still not seeing signs of leading, but I am going to reduce the load by .3 grains to keep the MV as close to 2,000 as I can with out going over it.. I hope to get more time to test some pistol rounds later this week.
Whoda thunk a standard primer would give a higher MV with lead bullets? I even went and double checked the box to make sure they were Remington LR standard primers, they were.
do you intend to test the primers themselves any further? I can't bring myself to imagine a Standard LR primer giving a HOTTER spark than a Magnum, but in this application it appears to give a BETTER spark.
AND, thanx for the info
bpost,
do you intend to test the primers themselves any further? I can't bring myself to imagine a Standard LR primer giving a HOTTER spark than a Magnum, but in this application it appears to give a BETTER spark.
AND, thanx for the info
I plan on retesting both primers with that load. I will then make sure both get shot on the same day so sunlight differences can't mess up the numbers.
You may be on to something about a better spark, getting the powder lit better and producing a different pressure curve thereby increasing MV.
I checked my primer stock this evening. I have both Winchester Mag large rifle and Winchester standard large rifle primers available. I will re-test using those primers so the manufacturing differences won't unduly influence the results.
This is FUN!