Help with 300 WSM build

[onlyfineknives]

Hey folks,

Looking for some input on barrel length and load possibilities with a 300 wsm build.

I have a Tubb ATR that allows me to load long so I am not constrained to a short action length.

Ideally, I would like to shoot the new Berger 208 or the Sierra 200gr 27 cal ogive bullet at 2950, but would be fine anywhere in the 2925 to 2975 range. I would like to use either H4350 or H1000 for powder.

Does anyone have any experience with these parameters to know if a 28" barrel throated long would put me where I need to be?

Thanks for your help!

 

[Orr89rocz]

I have seen 2800 out of my longer throated 24” wsm and 210 berger vld. i would assume with right powder 4” more should get near 20-30 more per inch. Look at the load data thread up top i think guys are in that range with 28-30” tubes

 

[ShootDots]

May I ask for the reason behind a 28" barrel? Is this going to be for F-Open, hunting or some other venture?

 

[onlyfineknives]

28" barrel is to give me as much velocity as I can get while still being short enough that I can do some long range hunting with it as well as some mid to long range shooting (1k - 2k). Just don't want it so long that it would be unwieldy in the field.

 

[rhovee]

Depends on your powder. H4350 would be a touch fast, may work. H1000 is too slow. Can't get enough in the case. H4831SC or RL23 would do it.

 

[ShootDots]

To get the velocity you need, my bet would be on N560 and RL-23. These will produce excellent accuracy as well as being true speed demons..

 

[MagnumW]

Measure mag length. Add .010 so you could load with .010 jam. Add .040 for throat erosion over life of barrel. Add .010 for clearance. That means oal of sample round should be .060 less than mag length.
So If mag is 3.990 oal is 3.930. Or assume .010 jump and allow for only .030 erosion so OAL = 3.960
Tell smith to Throat for the sample to touch the lands.

 

[DTubb]

Have done a few of 300 WSM - ATR platform
Schneider 5P 8 twist - 3.352"OAL
New TBN coated Sierra 200 gr
70.3- 4831 SC
3100 fps
28" fluted barrel
with the 5 Star brake set 2 revs out it shot nickel size 5 shot groups at 200yd.