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Tell me about the 7mm SuperMag....

2088 Views 7 Replies 4 Participants Last post by  PJ
What is the parent case ?
What velocity can you get from a 10" barrel ?
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It's not in my new book P.J.

Actually, my new book is a few years old. 2000 edition.
its from 357 max case

It is a 357 max case with a new neck formed. If I recall correctly you just run it through the 7 tcu sizing die or something. Velocities should be about the same as the 7 tcu. For more info I would check with someone like accurate arms. They have always been helpful with information seeking. :grin:
The 7SM is a 357 Maximum case necked down to 7mm and according to Sierra you can substitute 7TCU data for the 7SM......just think of the 7SM as a short necked 7TCU.

I've got a 14" factory TC Contender barrel in 7SM and really like 's a real tack driver.

I'm loading; Winch. 357 Max cases....WSR primers....Sierra #1900 120gr bullets....30.5grs of BLC-2....OAL 2.483.
Can you tell me if I can use 7 tcu dies or do I need 7sm dies ?
Is the 7sm easy to form and load ?
Monkey, I have Accurrate's new book, isnt in there...

They might have some data that isnt published though.
or 1-800-416-3006. they have always been real helpfull whenever I have called on the phone. They love their work there, and love to talk about it.
7 SM


You will need to get a set of 7SM dies, mine are Redding...... 7TCU dies won't work.

The 7SM is no more difficult to load for than the 7TCU......piece of cake.
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