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Knightflyer
04-18-2018, 02:36 PM
Okay, I'm reading as fast as I can, wherever I can, but had a question maybe someone can answer or point me in the right direction? I'm reading Lyman's Cast Bulllet handbook 3rd Ed currently, and have MUCH to learn.

Anyway, I was using Hodgdon's reloading tool, for a 30-30 load. I'd selected 170 gr bullet, with IMR 4064, IMR 4198 and H4895 selected as powders.

IMR 4064 & H4895 both had max loads of 31.7 & 30.5 respectively, CUP of 35300/35200 and vel over 2000 fps.

The IMR 4198 though was listed as max of 22.3 grains, with CUP of 32,100. Vel was a couple of hundred fps behind the other two loads, the pressure wasn't that high... why was the charge done so low? Is 4198 fluffy and the case was full? Is there some other reason? It just made me curious.
Dave

rking22
04-18-2018, 02:49 PM
4198 is faster burning and not considered an optimal 30-30 powder for jackets loads. They probably did not do a full workup and published just some boundary loads. Also could have been spiky , or pressure rise vs velocity rise became a logical limit. Check multiple sources, not to find the max you can pour in but to understand where the reasonable load range is.
My Lyman states that they consider the max load to be at accuracy falloff, cast manual. I like to see the pressures listed, especially for cast use, more data for a better decision.

Knightflyer
04-18-2018, 04:13 PM
Okay, that would make sense. I figured that there was probably a reason to cut it where they did.
Thanks!

rancher1913
04-18-2018, 06:42 PM
max loads are not always the most accurate. I have been know to max out some loads in my 25-06 just to see how they did and it did not justify the burn out of the barrel for a few extra fps. for somebody just starting out a good rule of thumb is to stay towards the minimum side until you get some experience, just in case a slip up is made somewhere, you have a little wiggle room.

if you think understand the why of some metallic loads are weird, just wait til you start shot-shell reloading-----------you know its only a mater of time til you go there :veryconfu