350 WSM - velocities very good with IMR4895

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Whelen B

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Thought some might be interested.

358 Norma Magnum loaders have often spoken highly of IMR4895 behind a 250 grain. I thought it might work in my 350WSM. So I just fired off some more Hornady 250RNs but this time trying IMR4895 and got quite good results - 2799MV with one load (chrony reading was 2789 set out at 12' ). Pressures seemed acceptable but nearing max I think - http://35cal.com/ruger77_350wsm.html

I may (???) get the same velocity from ReL15 with 250s but have to test some more.

I'm getting the velocity that I thought was reasonably possible with IMR4895 and am happy to this point. More to loads to develop of course as I'm just getting started with this new chambering. However I feel 2800MV with 250s will be about the best I can safely consider as a usable hunting performance ceiling. I may ammend that assessment as further testing may dictate.

With 225 partitions and the like I expect to reach around 2940MV or so - we'll see if that is safely doable. I'm not sure.

Also I think a 280 @ 2500+MV is very doable. That load would make a supreme dangerous game recipe. I just gotta mortgage my house to buy a box of 280 A Frames to try them. I think the length and shape of those 280 A Frames may be perfect for the 350WSM and the COAL I'm using. I've got some 300 Barnes Originals in stock which I will try too eventually. They likewise would be among the best for a 35cal stopping load (if there is such a thing-???).

Regards
 
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Sounds like a fine big rifle you got there. Your powder charges look pretty close to those for a .358 NM, so I assume case capacity is pretty close.

I keep looking at the info on that .358 Hawk from Z-Hat and going "Hmmmmm..." But... like I need another .358 caliber rifle in yet another caliber. Mental note to self: "Spend less time cobbling together new ones and instead spend the time and money shooting the old ones".
 
...so I assume case capacity is pretty close.
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Yes - right - 84.3 (350WSM) compared with 88 grs. (358NormaMag) water capacity. Plus in my past testing with other 35cals, I find the 250gr Horn "RoundNose" requires about a 1 to 2 grain greater charge than other bullets of the same weight for comparable velocity. Probably because it's short, less bearing surface, and ogive nets a long jump to the lands. So wth other pills like the 250SpeerHC and the 250HornInterlock "spirepoint version" I'm thinking a couple of grains less will give similarly good velocities - we'll see.

Mental note to self: "Spend less time cobbling together new ones and instead spend the time and money shooting the old ones".
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Oh ya - NOTE TO SELF - follow Rick's "mental note to self".
 
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