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View Full Version : The search for an accurate 50 caliber cast boolit.



Tnfalconer
07-05-2017, 10:52 AM
So as some of you know I have been working on this for a while. The thread on the rifle build has become all about the boolit instead of the rifle so I thought I would start this thread to separate the two.

I have been searching for a match grade, cast boolit to use in my 50-90 custom build. It has not been easy. I have researched to the "enth" degree and only been marginally successful in finding anything useful. There are many castings out there but I really wasn't satisfied with any of them. I felt like there was room to run in the area of 50 cal. Boolits and started in to design my own.

So a little background on the rifle. It's a custom build on a ruger no.1 action. The barrel is a Military contract run 50 BMG 1-15 twist chrome lined from a very well known manufacturer. We have used these barrels in the past and they have performed EXTREMELY well. I am building it specifically to shoot cast boolits over black powder as accurately as possible.

The first evolution was a casting from RockRat. The .510 rockrat that some of you are familiar with. It's a big guy.... 850grn, round nose with a wide meplat. Not ballistically all that great but a nice boolit for the 50 BMG. I started shaping this bullet on the lathe and did ballistic modeling based on the results. The results were pretty good. Next I lathe turned some lead bar to a desirable shape and modeled those into the program and really like what I saw so I moved forward to having a mold made to get as close as I could to that shape. I went to a couple of the custom mold makers and came up with some good ideas, having constraints, we weren't able to get exactly what I was looking for but we did get close. One of them is the Accurate molds 51-645Z. Tom made this mold up for me in a diameter of .508 to be powder coated. It has an overall length of 1.375, boat tailed with a .260 meplat.


I have a couple other molds on the way as well. Those designs are still a little experimental. All were designed by me with a good amount of help from others. There will be more to come. I have also written a few CNC programs to shape lead bar stock for the final shape if needed. Casting has limitations for sure. There is only so much you can do in that space. I plan to keep going back and forth with R/D then casting to get to my goal. I know it's a lofty one but I am looking for a cast, match grade bullet approaching a BC of 1.0..... We will see what it takes to be successful.

Tnfalconer
07-05-2017, 11:06 AM
This is the mold from Tom at Accurate molds. I should have one in hand shortly for testing, as well as a couple more new mold designs.