How to Calculate BHN for a Mix of Alloys??

[garandsrus]

Kevin,

Thanks for improving the spreadsheet I created. I didn't know the formula to predict the BHN.

John

[Barnowl]

Kevin,

Thanks for improving the spreadsheet I created. I didn't know the formula to predict the BHN.

John

Howdy John,
That is a very nicely done spreadsheet! Hope you don't mind that I messed with it a bit. I don't think of it as improving your work. The original intent of my edits was just to customize it for my own use but then I ended up posting it here when the alloy discussion started.

I found a formula for "Estimated minimum peak pressure required for bullet obturation" on the LASC site at http://www.lasc.us/FryxellCBAlloyObturation.htm and included it in this version. See attached, ver 1.1.

I am repeating the credit for the spreadsheet again here:

Attached is an Excel spreadsheet called "Cast Bullet Alloy Mix.xls" by John T. Larson that is very flexible for tweaking the mix to achieve the desired ratio of Sn:Sb:Pb. For my own use I made a couple of edits in the text at the top of the sheet and also added the formulas for BHN (8.6+(.29x%Sn)+(.92x%Sb)=projected BHN) as found in another post on CastBoolits and "Estimated minimum peak pressure required for bullet obturation" as found on LACS. It is nicely done and provides a lot of information.

Kevin

[LouisianaMan]

Thanks for this work, guys! I've got WW, but no pure lead yet, and had been wondering what options I had to effectively alloy it to give obturation and/or possible expansion in low-velocity revolver loads, such as various weights of .32SWL/HRM/.327, .38SPL, and .45LC.

This spreadsheet gives me some ideas to work from, and should improve both accuracy & leading issues. Excellent!

[leadman]

Thanks for all your work on this.
I have litterally a ton of pure lead and, some lino, and some reclaimed shot. This should allow me to mix up a good alloy for my purposes.