View Single Post
Rotometals bismuth T
Unread 05-19-2023, 09:35 PM   #1
Member
Milton C Starr
Forum Associate

Member Info
 
Join Date: Jun 2019
Posts: 1,501
Thanks: 475
Thanked 1,001 Times in 463 Posts

Default Rotometals bismuth T

I saw rotometals was selling limited quanties of bismuth Ts, I had planned to eventually buy a mold and cast some to test. Though I dont have the time for that right now and the mold is $200 or so. I figured these small 1lb bags would be good for testing in the 8 and 10 gauge.

A lead T weighs 16grs according to my scale or about that given a little variance. The Bismuth T weighs 10grs and a steel T is 8.4grs according to Ballistic products. Looking at the math for 50 yards here are the numbers I came up with.

Steel T 50 yards - 1500 fps muzzle velocity.
746fps 10ft/lbs

Bismuth T 50 yards - 1200 fps muzzle velocity.
739fps 12ft/lbs


The difference in loading the bismuth vs lead for the 8 gauge is 2 1/4oz of bismuth takes 1/8" less felt wadding to get the same roll crimp height. I am planning on having these tested, I would like to see if I can develop a reasonable pressure bismuth load with buffer.
Milton C Starr is offline   Reply With Quote