So, I recently ran onto a loading data tool from midwayusa. Called Loadmap. It's new to me but was probably something they included with reloading components or something like that.
The data in loadmap is all in PSI. NOT cpu. I was looking over all the loads,. and see that they've derated 2400 wayyyyyyy down from the original 357 mag load. Seems like a 158 gr. gas check load is down in the range of 12 grains of 2400. The original 357 load is common knowledge,...I believe it was 15.3 or 15.5 of 2400 under a 158 gc. (It's still in lyman data as far as I know). So, I looked up the loadmap data on 44 magnum 240 grain,.. and the 2400 data is extremely anemic as well. Coming in around 20 grains (I believe even Elmer keith was running specials at over that amount). In both cases the current data was listed in psi.
So,.. I am wondering if they 1) got a fast batch of 2400???? or 2) 2400 has a weird pressure curve with a spike in it somewhere. I'm not terribly worried about a spike,..I'm sure when those guns for those cartriges were made originally, they tested them to the point of blowing up and then scaled back to a safe amount. If they were using cpu at the time, a pressure spike "that hasn't changed unless the powder has changed" means little except they now know it is there. Obviously, if it did mean something,...then their safety margin accounted for it.
Does anybody have a take on this.???? I generally do not use 2400 for 44 mag, just H110. So the 44 mag data doesn't matter much in my case,.. HOWEVER,..I have been loading 357 158 gr. gas checks @ 15.+ grains 2400 for many years,.. And this caught my attention. I do intend to keep doing it, but that particular data is unsettling. My 357 wheelguns are all ruger. I also have a rossi 92 lever in 357.
If this has already been discussed just point me in that direction.
One more thing,.. I have NEVER been able to find an "original" 44 mag. load, other than it was remington 240 gc, and stated velocity was 1570,..also 2nd year of 44 mag production, winchester started making 44 mag ammo and was over 1600 fps.? Since it's really just the 2400 that has me perplexed, and not all loads in general,..I'm not sure whether I can just chalk this up to CYA,..? Maybe that's the only explanation.
....Oh, 2400 is usually my go to powder for my 454,.. But I didn't mention it because the cylinder walls are so thick I do not think it would even be possible to blow up a 454. (Not that I would pack one full of bullseye).