Re: Any advantages to increase barrel length on WSM cartidges?
The biggest factor in what efficiency you get out of your barrel is the type and speed of the powder you use which will have a lot to do with the bullet(s) you choose. RL17 is a fairly efficient powder for shorter barrels (like 24") and is a great powder in the 300 WSM for a fairly large range of bullet weights on the heavier end of the scale like 165 and up. You will surely see more efficiency and velocity with longer than a 24" barrel. How much, I'm not sure. But if I were to build another 300 WSM, I would go for at least a 26" barrel.
Now, if your priority is a good shooting short barrel (24") cartridge, the 300 WSM is a very good choice, especially with RL17.
In my factory 24 3/8ths barreled 300 WSM, I got 3200 fps with 180 E-Tips and 2930 fps with 210 LVD's using RL17. Very good velocities IMO. With another couple of inches, I could probably have got another 50 fps or so.
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