338 WSM Loads

[LeMay]

I'm looking at getting my 300WSM rebarrel to 338MSW and was looking for some starting loads for the 250gr and 300gr SMK for it.

Thanks LeMay OUT

 

[James Jones]

I load the 180 , 225 accubond out of my dads 338WSM , with a stiff load of N550 I can get the 225 Accubond to 2900fps. , we tried some 250gr SMK's but the barrel is a bit short and the twist i think was a little slow for those speeds.
I think that the WSM case may be a bit small for the 300gr SMK's , but I think that with at least a 26" barrel you could get them to 2500fps out of the WSM

 

[LeMay]

I was looking at putting a Mike Rock 5R barrel on it. I see makes a 27 inch barrel and was thinking about it being 27 inch. Do you think you could get 2650 with the 250 SMK? Who make a good set of dies for it. And what would be the best brass to get.

Thanks LeMay OUT

 

[James Jones]

Well the 300WSM (338WSM Parent) holds abit less powder than the 338 Winchester mag and I now that the old 338 winchester can get the 250's up to 2700+fps with a 26" barrel and the 300WSM can get the 220gr bullets up to 2700fps with a 26" barrel.


I'd say that with the 27" barrel and the 5R rifleing that you should be able to get to 2650fps or **** close to it , you may even get a bit over it.

the 338 WSM is a bit more powder effecient than both the 338 win mag and the 300 WSM , and the 5R rifle egneraly does help with increased velocity.

As for brass , Winchester is good stuff if you go throught he trouble of sorting and case work , the Norma is the best for accuracy sake but its coslty and soft so if your running high pressures it won't last.

I had to make a set of dies , I'm not sure how big Redding goes up with their neck bushing but if they go big enough you could use their 300WSM dies with a bigger bushing.

 

[LeMay]

I've ben doing a little more reading on it James Jones. I'm thinking about going with the 250 gr SMK Fed 215m primers and Norma brass. Now I just have to get a powder for it and a starting load. Id like to get about 2600fps with at bullet and a 3/4 MOA. Maybe 1/2 moa would be great. Maybe N550?

Thanks LeMay OUT

 

[James Jones]

The N-550 is close to the same burn rate as H-4350 but offers a little better load density and it meters very well ,the N-560 may be a better choice if you have a , little longer barrel as its burn rate is a bit slower ,about like 4831 and R-22