by noylj on Sun Jun 25, 2017 4:15 am
>.40 S&W 180gr Flat-Point Plated bullet over Bullseye load. (Berry's to be specific...
What is wrong with the general "use lead bullet data for plated bullets?"
What is wrong with "use start to mid-range jacketed bullet data for plated bullets," IF the manufacturer says it is safe to do so?
Well, lets's see what Berry's says.
Berry's says on their web site:
"You can use published load data for lead/cast bullets or low to mid-range FMJ data, as long as it is the same weight bullet. Berry's offers our standard plate bullets which can handle velocities up to 1,250 fps and 1,500 fps for our Thick Plate (TP) versions...
We recommend a light crimp on the bullet, just enough to put pressure against the bullet without denting or deforming the plating. If you were to pull the bullet out of a case with the proper crimp you would find no more than a scratch on the surface of the plating. If you are denting or deforming the bullet, your accuracy will suffer and the bullet may start to tumble before it hits the target."
Beyond that, as part of always being as safe as possible, I always start at the lowest start load I can find. I may only fire one or two rounds (to check function and inspect fired case and such) before working up. Reloading is all about the fact that components have an effect and NO manual can tell you exactly how any bullet will perform with your mix of components (even is the manual used "the same" bullet), thus the need to start low and work up. Safety first.
A good source of compiled data would be Richard Lee's #2 manual where he separates lead, jacketed, plated, etc. In #2, he shows:
180gn jacketed with 5.0gn Bullseye start and 5.5gn Max
and
180gn lead bullet with 4.2gn Bullseye start and 4.5gn Max
(He only has plated data for AA2, AA5, AA7, and AA9, and XTP data for Accurate and Hodgdon powders).
Hornady lists 3.9gn start and 4.6gn MAX for their HP/XTP.
Speer #12 (and the Alliant site) shows 4.9gn start and 5.5gn MAX for 180gn TMJ or GD-HP, both plated bullets.
My method is to check every source I have, and I see:
Start loads in manuals for either all 180gn jacketed bullets range from 3.8-5.0gn of Bullseye, with max loads of 5.5-5.6. Since I don't know how my lot of powder or particular bullet will act, I would work up 4.0, 4.4, 4.8, 5.2gn and see how things progress.
Start loads in manuals for either all 180gn lead bullets range from 3.4-4.2, with max loads of 3.8-5.3gn. So, I would consider that one manual with a MAX load at 3.8gn as a warning NOT to assume anything, and I would work up 3.4, 3.7, 4.0, 4.3gn and see how it goes.
If I looked at both sources, I would still feel safest starting lowest, but that is me. I would rather waster a few bullets and make sure the loads are safe.