norma 270/300 WSM to 7mm WSM

[twoodard]

so the Win brass is just not lasting past a second firing in my 7mm WSM. thinking of going the norma route. due to shoulder dimensions being different the brass will need sized and fire formed. of the two would the 270 be better? neck it up past, form a false shoulder then back down to 7mm. or run the 300 with the false shoulder? Ive used this method before but for 6BR to BRX.
either way will need formed so without burning up the barrel I would like to use the cream of wheat method as its worked well in the past. question here is how much pistol/shotgun powder to use? thats a big case. thanks guys

 

[expiper]

skip the cream-0-wheat....use aprox. 55% of case volume of Universal Clays.....a lil 1/4 square of toilet paper....and pull the trigger.....after a few you will see if u need more or less powder....very simple and no gunk or mess in the bbl or action.....Roger

 

[RDavies]

How about, neck turn as a 30 cal, then neck down to 7mm with a false shoulder, no chance of donuts then?
As for fireforming, how about Trail Boss, can you get that? Just load cheap 7mm bullets behind 2/3rd case (maybe 16 gns) and fireform with it. Your barrel will still be cool after 20 shots.