+*updated*

No it wont, It does with a 150 or 165gr. bullet but step up to the heavier longer bullets were the B.C. is optimal, it has to be seated farther in the case because of the short action. You loose case capacity, which in turns means lower velocity. The bigger case will always come out on top. If you built it on a long action with a longer throat, so you could seat the bullets out farther, but you cant do that with a short action unless you have a single shot bolt gun.

Great comparison Ridge Runner! LMAO!!!

And chambering a WSM in a long action makes as much sense as Obamalamadingdong getting the Nobel Peace Prize!!

Haha...that's assuming either one will even start!!

Depending on the powder used. You can get 6 to 8 grains more powder in a 300 Win Mag case than you can a 300 WSM. So there is a bit of difference in reloading. Using the exact same powder in both cases the 300 Win Mag wins that argument hands down. Shoulder design may have the advantage to the short mag but if it out gains the Win Mag using the same powder charge then it also means it wins the pressure category too and that's not a good thing. I've studied both and the amount of difference isn't worth arguing about until you hit the reloading bench.

i have 2 short mags one chambered 243 and a 300.my buddy is a competition shooter and has put these 2 guns together for me thet both have kreiger barrels and bat actions and hs precision stocks with 8 twist barrels and i had him make barrels short for easier hunting with out 200 yards the 300 punches holes at .750 for the 300 and the 243 is .675 thats good enough reason to own a short mag in my opion.

What .243? A WSSM or is it based on a WSM?

Now, I have reloaded for one WSM and two 300win mags. And I have to say the WSM didn't seem quite as finicky as the win mags. But for me and my style of hunting. I could throw either in the air and hunt with either.

my hart rifle in 300 hart doesnt shoot that well which to me really aint no difference than a 300 win mag,