300 Grain .358??
- Thread starter B
- Start date
B. If you have a factory 1/16 barrel it may not stabilize 300 grains. 1/12 certainly does, 1/14 does in my experience. The heaviest cast bullet commonly found is the Lyman 358009 which weighs 287 grains from the alloy I use although I'm sure you could find a heavier mould some where with a bit of research. There are some heavy jacketed bullets available from a custom maker but his name slips me. Do a search on the AR forum under medium bores as I think they were discussed there.
- Location
- Somewhere on the Hudson Bay Coast
A 300 gr mono-metal .358 bullet would be very long. In this weight, even a lead core bullet should be a round nose flat base style to make the bullet as short as possible. If you intend to load for a medium capacity cartridge with a short neck, or if your rifle has a minimum length magazine or short lead, the loss of powder capacity due to seating the bullet deeply would reduce the powder capacity and might result in a significant loss in performance. However, if your cartridge can generate 2400 fps from such a bullet I am sure you would see excellent performance, if the twist of your barrel is fast enough to stabilize the bullet. I would expect a 1:12 would be the minimum twist required. If you choose a cast bullet a flat nose design with parallel sides would minimize the length although your velocity is unlikely to exceed 2000 fps.
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I was hoping to hit pretty close to 2400fps but I really think that would be pushing it. A 300 grain in sort of a semi wadcutter is what I was thinking would be ideal. It would be a strictly short range setup, under 100m and I would be using it for defense. Sounds like I have neither the proper barrel or powder capacity to make it a good choice. I guess I will have to try the various premium 250s to find a max performance bear stopper. Thanks to everyone!
