7WSM conversion

skipglo

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I've got a full custom rifle in 7WSM. It has a 25" Bartlein 3b with an 8.5" twist. The Borden action is (I believe) a magnum face short action. Never having the option of quality brass (without converting from other WSM cartridges) has grown tiresome. What can I rechamber the barrel to that would have high quality brass available?
How much do you plan to shoot this gun! 100 brass of any make will give you 5-600 rounds. Seems a shame to go thru the expense of rebarreling a good custom before its time....just me!
 

phorwath

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I know Hornady is not ADG or Lapua but they’re making some pretty darn good 7WSM brass now. Requires some prepping and annealing but seems to be pretty darn good stuff.

Hornady brass has good strength in the case head, and the primer pockets hold tight under pressure?
 

phorwath

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Good to know. Hornady's PRC cartridge brass is supposedly toughened up also. Compared to some of the casings they've sold in years past.
 

jgs8163

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Here’s a pic of the Hornady 7WSM brass after prepped and annealed. Chamfered, flash holes uniformed, necks expanded and sized. The 300WSM was done the same and is performing very well. Have not shot the 7 yet, rifle is at the smith getting some upgrades done.
image.jpg
image.jpg
 

JuddL

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Lots of good info posted. One rule of thumb I’ve had after setting a barrel back only to see minimal barrel life gains. If you have a lathe and can do it yourself (meaning not paying a gunsmith) then set backs or changes are worth it.

But a gunsmith is going to charge the same to do a new barrel versus a setback…just get a new barrel.

Good luck…I’m biased, but building a 300wsm and 6.5 saum…both good options with brass available. This will be my second 6.5 saum as a buddy wanted my first one worse than I wanted to keep it.
 

grouse

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7 WSM is a good cartridge. I shoot one using Norma .300 WSM brass and neck down to 7mm. A little bit of case prep and you will get 4 - 5 reloadings each.

The 7 wsm is longer than the 300 wsm. How do you account for that?
 

-WARDOG-

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More like the .30 shoulder is shorter than the 7mm - just slightly. Better than the other way around.
When you chamber the shorter .30 into the longer 7mm chamber and fireform, Bada-Bing!
The case length is the same.
I use bushing dies to neck down in two stages.
I internal ream to remove the donut build-up, then neck turn.
My neck TIR is .003 - .005"
I have not annealed yet after two firings of 250 cases I spent all winter prepping. I have the tools to anneal, just haven't done it yet.
I am not pushing the bullet hard, a 180 Berger VLD-H @ 2780 fps with RL-25 in a Surgeon Scalpel 26" Krieger.
Accuracy is superb at .2 MOA.
I just got my hands on RL-26 and will be working a load that will get my FPS up about 130 fps.
 

Varmint Hunter

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I've been using fully prepped Win brass and have had good results but it seems to vary. Different brass lots are often inconsistent. The 7WSM is the only cartridge that I shoot where high quality brass isn't available. Since the cartridge is drifting into obscurity I'd prefer to move in another direction.

It looks like all three of the Sherman 7mm cartridges will work with a minor setback of the barrel.
 
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