270 wsm brass in a 300 wsm

[wcat]

Hi,
I'd like to know if it's possible to run new 270wsm brass in a 300wsm resizing die to load them for my 300wsm.
I have 270wsm brass unused on the shelf.
Thanks

 

[jeff270]

I'll say yes because I've done it.

 

[Eagleye]

Not a problem. The one that is different is the 7mm WSM. [different headspace dimension] Dave.

 

[wcat]

Thanks! !

 

[c-fbmi]

Yep, or you can just shoot factory 270 WSM in your 300 WSM and presto, you have 300 WSM brass..........and no it doesn't hurt your bore in the slightest.

 

[Cleftwynd]

Not a problem. The one that is different is the 7mm WSM. [different headspace dimension] Dave.

This is one that puzzles me, what was Winchester thinking by making the 7WSM 0.040 longer headspace than all the other WSM offerings. Makes no sense. The 7-300 wildcats make much more sense.

 

[Therion]

This is one that puzzles me, what was Winchester thinking by making the 7WSM 0.040 longer headspace than all the other WSM offerings. Makes no sense. The 7-300 wildcats make much more sense.

The distance from the base of the case to the shoulder is 1.664 in both the 270 WSM and 300 WSM, whereas it's 1.7018 in the 7 mm WSM; I believe that is so you do not put a 7 WSM cartridge into a 270 WSM rifle. Similarly, the same distance is 1.948 for the .270 Win but it's 1.999 for the .280 Rem, again so you don't put the cartridge with the .284 bullet into the rifle with a .277 bore.