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Absolute Hammer load data

When I was testing the AH I got primer leaks on a couple powders pretty quickly before hitting much for other pressure signs.
Okay so it's a thing. I didn't know whether to blame the powder, the pill, or my prep. Great. Did you loosen pockets? I've heard of rl26 doing that as it's only pressure sign.
 
Okay so it's a thing. I didn't know whether to blame the powder, the pill, or my prep. Great. Did you loosen pockets? I've heard of rl26 doing that as it's only pressure sign.

On at least one powder I blew a primer on the exact same load that leaked the outing prior, so in my case I was definitely hitting enough pressure to loosen the pocket!
 
When I was testing the AH I got primer leaks on a couple powders pretty quickly before hitting much for other pressure signs.
Okay that's super interesting…im forming some experienc based opinion/theory about internal ballistics based on findings.

The secret to hammer bullets being able to achieve higher vel before hitting pressure is entirely in the reduced total bearing surface because of their geometry. That's not theory that's just plainly so.

But I've observed that light weight monos of non hammer geometry can also be loaded to significantly higher foot pounds of muzzle energy than heavier pills before hitting any signs. I don't fully understand why but suspect it's all about bearing surface and pressure spikes.

I have a .300 win mag load featuring a hbn coated 120 Barnes tac at 4050 fps. That's basically 4400 foot pounds. Hot. Easy one finger bolt lift. Case dribbles oit, no extractor mark, no cratering, no loosening of the pocket, no excessive case growth or web expansion as deduced via micrometer. 2.5 grains above this load I had a sooty case head! No other pressure signs even then.

I have loads with the 225 eld m that are abojt 2800 fps and 3800 foot pounds. Very safe. But big extractor spot on those.

Interesting. The trick is the hammers can have the minimal bearing surface of a lightweight even with long heavy bullets too.
 
Okay that's super interesting…im forming some experienc based opinion/theory about internal ballistics based on findings.

The secret to hammer bullets being able to achieve higher vel before hitting pressure is entirely in the reduced total bearing surface because of their geometry. That's not theory that's just plainly so.

But I've observed that light weight monos of non hammer geometry can also be loaded to significantly higher foot pounds of muzzle energy than heavier pills before hitting any signs. I don't fully understand why but suspect it's all about bearing surface and pressure spikes.

I have a .300 win mag load featuring a hbn coated 120 Barnes tac at 4050 fps. That's basically 4400 foot pounds. Hot. Easy one finger bolt lift. Case dribbles oit, no extractor mark, no cratering, no loosening of the pocket, no excessive case growth or web expansion as deduced via micrometer. 2.5 grains above this load I had a sooty case head! No other pressure signs even then.

I have loads with the 225 eld m that are abojt 2800 fps and 3800 foot pounds. Very safe. But big extractor spot on those.

Interesting. The trick is the hammers can have the minimal bearing surface of a lightweight even with long heavy bullets too.
Interesting. How sooty is too sooty btw? I had a small amount from the getgo and I know I was totally safe then.
 
I don't mean sooty on the case, that's fine. Like black leakage around the primer. You get that from the beginning?
No, the last one was definitely wisping out the primer sides. It took a second to tell it was coming from there but it was definitely black around the primer once you got the right angle. That's where I quit.

The rest of the shots just had a gray film on the case head with no clear source. Maybe a streak around the lettering, maybe just a film all over the head. I've never seen it before without a primer actually coming out and I've developed a decent number of loads. It showed up on loads that would be below max for anybody's conventional 140g data.

I put scotch pad to the cases which I've never done before to overcompensate for leaving some too slippery last time, which gave me crazy ejector readings. My thought was maybe the case was grippy didn't slide back as fast, leaving the pocket less supported. I don't know if that stands up to scrutiny, just a thought.
 
No, the last one was definitely wisping out the primer sides. It took a second to tell it was coming from there but it was definitely black around the primer once you got the right angle. That's where I quit.

The rest of the shots just had a gray film on the case head with no clear source. Maybe a streak around the lettering, maybe just a film all over the head. I've never seen it before without a primer actually coming out and I've developed a decent number of loads. It showed up on loads that would be below max for anybody's conventional 140g data.

I put scotch pad to the cases which I've never done before to overcompensate for leaving some too slippery last time, which gave me crazy ejector readings. My thought was maybe the case was grippy didn't slide back as fast, leaving the pocket less supported. I don't know if that stands up to scrutiny, just a thought.
I just resized and primed the leaky case and there may have been a very, very slight loosening of the pocket. Maybe. Most likely not. It's tough to tell, but it definitely wasn't trashed. I'm the second owner of the cases, some were less tight rom the start.

Either way after looking at the brass again I'm calling it, going to load for 3400. That's what my gut is telling me, and it's what my goal was. I matched Steve's 280ai/h100v results with low volume brass and temp stable powder, and I think I remember him saying somewhere that was a barnburner for the 280. Open to correction.

If someone wants to send me some RP and nosler Saum brass and some bolt head component springs I'll happily put it back on the data grill.
 
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