StuBeef302

Last but not least... (in hindsight the primers don't look bad)

I just noticed I had an excel error (an fixed it, my Std Dev was a tiny bit better with the larges too. Probably not enough to be reliable. with only five shots, and a 2 fps std dev improvement, it could easily go the other way with more shots.

Velocity Data... LOAD DATA: 300BLK, 150gr Hornady FMJ, COAL 2.098", Hodgdon CFE-BLK v1 v2 v3 v4 v5 Avg std dev Group 1 (sm primers) 1633 1646 1652 1657 1674 1652 13 Powder 19.5 19.5 19.5 19.5 19.5 LOAD DATA: 300BLK, 150gr Hornady FMJ, COAL 2.098", Hodgdon CFE-BLK v1 v2 v3 v4 v5 v6 v7 v8 v9 Group 2 (lg primers) 1581 1613 1620 1640 1674 1679 1685 1691 1718 Powder 18.8 19.0 19.2 19.4 19.6 19.8 20.0 20.2 20.4 LOAD DATA: 300BLK, 150gr Hornady FMJ, COAL 2.098", Hodgdon CFE-BLK v1 v2 v3 v4 v5 Avg std dev Group 3 (lg primers) 1642 1657 1660 1666 1674 1660 11 Powder 19.5 19.5 19.5 19.5 19.5

wouldn't you expect faster and more consistent speed with a light target load and more primer? The greater amount of priming compound ignition getting into that loose powder more thoroughly. Just a thought. Doesn't loose powder in a target load generally result in a worse Std Dev? More priming compound should make that better I'd think. (I'm no expert though)

I forgot to mention, the Small primers were Remington 7 1/2, and the Large primers were CCI 200.

Back from the range, no blown-off face. Hooray! My reloading disclaimer: don't do what I do, you'll shoot your eye out, also you may blow your face off, also you may die. I loaded 3 sets of 300BLK rounds, all using the same bullets: 150 gr Hornady FMJ-BT and same powder: CFE-BLK All tests were done with a 10" AR upper loading only one round at a time using a single shot filler block in place of a meg. Set one: 5 rounds of plain small primer, 19.5 gr of powder as a benchmark. (this has been my most consistent load with this bullet and powder.) Set two: 9 rounds of ladder test with cases modified for lg rifle primers, starting with 18.8 gr of powder and ending with 20.4 gr in 0.2 gr increments. Set three: (presuming I didn't see too much pressure sign in the ladder) 5 rounds of large primer modified cases, 19.5 gr of powder to compare to the benchmark. The benchmark (Set One) yielded an Average Velocity of 1652 fps, and a Std Dev of 13 fps The comparative large primer set (Set Three) yielded an Average Velocity of 1660 fps and a Std Dev of 11 It was o-kay overall. The ladder set was also a very nice curve. BUT, lots of pretty flat large primers. Only the slowest two had no pressure sign, with nice curved primers. An interesting thing is that there was no pressure sign at all other than the flat primers, all the way to max charge. No sign of a crater into the firing pin relief, no sign of ejector wipe, no sign of extractor wipe or tearing. Nothing. Just flat primers. I won't bother with this experiment again, the primers seemed too flat to me. I have to say I am a bit surprised, The load data that refences case pressure for the CFE-BLK loads (Hodgdon and Lee) both say that case pressures in this load are expected to be about 10,000-15,000 less than other powders for a similar velocity. So whatever the heck you do, don't try this test with any higher pressure powders (which is everything else) I'll post pics of the fired cases soon and the velocity data too. Adios

I agree, I’m happy about all the new gun owners too. If their demand is the reason for the shortage, it’s worth it. More gun owners = more 2A voters. It might not be 1 to 1 but I’ll take any percentage. More 2A voters = more freedom baby!

I'm going to use Hodgdon CFEBLK because the pressures are significantly lower than anything else for this cartridge. 150gr FMJBT. I'll let y'all know...

Finally primed...

Compare the batch of large pockets to the small pockets...

Here's where I'm at folks... First, setup in lathe with carbide tool:

My Bad, you are correct Danny, it definitely weakens the case head. My only point was that thicker head brass with a large primer pocket will not be as weak as thin headed brass with a small pocket. I’ll post some info.

Hi p226, I did mention above that I analyzed that already But! It’s been the pit of winter for a couple months where I live, but we should have a few above freezing days in a row, I’ll get out and post some pics.

Oops, saw all the shavings on the right tool, didn’t notice the depth ring on the left tool. Nice.