Hi,
Last year with help from fellows including Arnie, I designed a DDPP bullet for my Browning BPCR, .45-70. It was designed to be patched with BACO .0020” paper and the belted portion to be a slip fit in a fired unsized case. Brooks made the mold and it was very close, within a thousandths, of the print and the bullet drops easy from the mold. Alloy is 16:1, 83gns Swiss 1 1/2 , .065 LDPE wad, and patched to the base. BACO paper is used and the bullet is a very light slip fit in the case. Seating depth is .075” . You can carefully lift the case up by the bullet but a little shake and the case will drop away. Accuracy is sub MOA at 100 yards and opens up to 1.7 MOA at 200. Not what I would call great but not bad.
Below are photos of the bullet along with the bullet dimensions along with the wrapped dimensions. The bore of the rifle is spot on at .450” measured by slugging at the breech end. Star brass and wall thickness at neck is .0095”. The bullet marked with a W was patched Hyde style and you can see the imprint of the folded patch in the bullet base. Both bullets fired into my swimming pool. They show a lot of base deformation, how much this affects accuracy is a guess but it can’t help. With the thin paper the base diameter is still over groove diameter by .0012” but the bore diameter size is so small I can about hear the bullet rattling down the barrel...the accuracy is minute of barn door. Loading was fiddle with this thin paper as the bullet was loose in the case.
Thoughts?
Cheers Richard
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