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Total Safety
09-12-2016, 08:23 PM
Hello

I purchased some cast bullets from a local gun shop and have a question about load data. They are .45 ACP 200 gr RNFP and the store/manufacture come highly recommended. My Lee, Lyman and Spear manuals address only their specific bullets.

What powder adjustment, other than starting minimum load, do you make for cast versus jacketed bullets? How about minimum over all length?

Thanks for any help.

DocSavage
09-12-2016, 08:29 PM
You can use the data for cast 200 gr swc the only thing you'll need to do is adjust your oal.

pjames32
09-12-2016, 08:30 PM
The Lyman cast bullet handbook will be your friend.
PJ

Total Safety
09-12-2016, 08:51 PM
The Lyman cast bullet handbook will be your friend.
PJ

Thanks for the advice. I was told that all molds are not the same. I refer to books listing cast bullets by mold numbers. Since the ones I purchased are made by a local shop and they use their own designed molds, is their a general rule of thumb to approximately compare one cast bullet from another? Also, how do you adjust for cast versus jacketed since that is what most manuals list?

OS OK
09-12-2016, 09:05 PM
On odd casts that are not in the book I try to match as close to the profile and weight as possible. I pay attention to the total bearing surface area of the drive bands. I figure that the more surface/contact area makes a pressure difference that would increase, so if my unknown cast looks to have more, I'll start off a little lower, 2 or 3/10's than where I might have if all was the same. I generally start in the middle of the load stats.
At this point I'll watch the Chrono and pay close attention to the primer flatness as I work the load up, especially if I'm trying to speed them up a bit.
The more load manuals/books that you have, the better off you are in trying to extrapolate. I avoid load calcs on the web if at all possible.

Joe K
09-12-2016, 09:11 PM
The three manuals that you list show data for 200 gr swc and would begin using those starting loads. I would make some dummy rounds with your boolits to make sure they fit your magazine and chamber. In my experience I hade to adjust the crimp also. I was shaving lead until this was corrected. Also clean out the copper. As far as comparing I try to use one that is close if not then by weight and use starting load data. Hope this helps. There is a lot of information here.

Total Safety
09-12-2016, 09:54 PM
Thank you all for your advice. I was concerned because the OAL was less than the minimum listed for some powder loads. I'm guessing it's because it is not a round nose.

gwpercle
09-13-2016, 01:20 PM
Get a manual or two that has cast boolit data. Trying to extrapolate data from jacketed to cast can get the inexperienced into trouble. After gaining some experience you can safely do it , but I find it best to use cast boolit data for cast boolit loads.
There are enough ways to go wrong in the handloading game. This is where guessing can get you in a fix!
Load safe,
Gary