31 August 2002, 16:26
<giladad>7WSM
Just picked up my A-Bolt 7mmWSM. How can I find some reloading info on this new caliber?? Hunt season starts soon, want to be ready!!!! Anybody know a good starting load w/ nosler bt's?? Can you use 7mm Rem Mag reload info??
01 September 2002, 05:53
<Don Martin29>I am looking for data also but my rifle is not here yet. Don't use 7mm Rem Mag data as the case is much larger.
You can use data for the 270 WSM or 7mm SAUM I would think and that is in the Nosler #5. I loaded up some test rounds using the Ladder Technique, the Powley Formula and looking at the various loading books and similar cartridges.
I think data will be out soon. Tell me what powders and bullets you have and I will work up a load for you.
01 September 2002, 12:58
<CAL9 from planet Fargo>YOu could contact Sierra and see if they have any data available yet. I purchased a 260 Rem shortly after it came out and they sent me all the data they had at that point.
CAL9
01 September 2002, 13:49
Marsh MuleGo to nosler.com and I think it's Accurate powder's web site for data on the new Magpro powder.
MM
![[Big Grin]](images/icons/grin.gif)
01 September 2002, 15:05
<MontanaMarine>As a last resort,
Refer to .280 Ackley Improved data, find the slower powders for bullet weight, reduce by 10%, and start working up 1 grain at a time.
MM
02 September 2002, 07:53
monteroa bit out of topic, but is the 7WSM case body longer than the 270WSM and 300WSM?
montero
02 September 2002, 13:37
Marsh MuleI believe they are all Identical except neck size.
MM
02 September 2002, 13:49
<Don Martin29>I heard the 7mm WSM was redesigned to be longer from base to shoulder so as not to chamber in a .270 WSM. But I have no dimensions.
02 September 2002, 14:10
Mauser98There is an article by Jon Sundra in the March/April 2002 issue of Rifle Shooter that describes the differences(besides bore) between the .270 WSM and the 7mm WSM. Apparently they were both to be simply necked down versions of the .300 WSM. However, someone discovered that a 7mm WSM cartridge could be chambered in a .270 WSM rifle. This was in pre-production versions. So a decision was made to lengthen the headspace dimension of the 7mm. According to Sundra, the headspace dimension for the 7mm is 1.769"(+/- .005") and the headspace dimension for the .270 WSM is 1.731". A difference of .038". There is no change in the overall length of the cartridges so the neck on the 7mm is shorter.
The same treatment was done to the .280 Rem in 1956 when it was discovered that the proposed 280 would fit into a .270 Win chamber.