How touchy is N570 with jump/jam

hemiford

Well-Known Member
Joined
Oct 7, 2013
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423
Also, with solid copper bullets, if they are touching lands, can pressure build that much quicker
than a cup-n-core that is touching lands ?
I will be eventually loading for 7stw and 338-378, heavier bullets.
 
IME, N570 is certainly a powder that warrants slowly working the loads into "corners" like jamming a solid into the lands might become.
I shoot it in a 28N with 195s and N570, does very well.

Also the 169 Hammers, but they are a little hotter. I am actually thinking of pulling all of those bullets and starting over. Too near max load for my liking but very accurate. Very hot here in TX already this year, over 100 actual and index close to 110, temp variations are magnified in weather like this. I try to err on the side of caution when reloading and find an accurate load somewhere less than max.
 
IME, N570 is certainly a powder that warrants slowly working the loads into "corners" like jamming a solid into the lands might become.
I shoot it in a 28N with 195s and N570, does very well.

Also the 169 Hammers, but they are a little hotter. I am actually thinking of pulling all of those bullets and starting over. Too near max load for my liking but very accurate. Very hot here in TX already this year, over 100 actual and index close to 110, temp variations are magnified in weather like this. I try to err on the side of caution when reloading and find an accurate load somewhere less than max.
Thanks RB, I read that some of the double base powders, particularly N570, like to burn under pressure
giving higher bullet speeds with more pressure. But boy, NOT TOO MUCH PRESSURE, whatever that may be.
 
IME, N570 is certainly a powder that warrants slowly working the loads into "corners" like jamming a solid into the lands might become.
I shoot it in a 28N with 195s and N570, does very well.

Also the 169 Hammers, but they are a little hotter. I am actually thinking of pulling all of those bullets and starting over. Too near max load for my liking but very accurate. Very hot here in TX already this year, over 100 actual and index close to 110, temp variations are magnified in weather like this. I try to err on the side of caution when reloading and find an accurate load somewhere less than max.
I use H1000 in my 28N with the 169gr HH, very accurate and temp stable in our climate.
 
I use H1000 in my 28N with the 169gr HH, very accurate and temp stable in our climate.
I also have a load for the 195s using H1000. Will probably do the same for the HHs, just load what I will shoot in the near future with the appropriate load. H1000 works very well in the 28N albeit a little slower. Hard to not take the speed when it comes with accuracy, but there were pressure signs when I loaded the HHs, but not enough to drop the load until now and its 110 outside
and I want to go shoot it. LOL.

I am not really that stupid, I just look that way!!!
 
If I read this correctly, the pressure testing done on hammer bullets indicated very low initial starting pressure,
about half what one would normally expect. I dont remember if any of these were jammed but it will tell you.


 
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