Home Forums Hunting & Shooting Hunting Rifles Winchester SA Magazine Box Length

Does anyone know the max OAL for a cartridge using a Winchester M70 SA? There are some cheap M70 Ultimate Shadow rifles with CRF actions and I figure I might use one for a build. New barrel and stock and it should be good to go. Just don't know if I need to go LA or if I can use a SA. Thinking x57 case of some type. Maybe 257 Bob, maybe 7x57.

This isn't precise because I measured these quickly with the rifle assembled and I can't get the caliper perfectly positioned. I measure about 2.83 to 2.86 inch. Ought to be OK for Roberts and for some bullets in the 7mm Mauser but not much room to spare.

Hmmm....LA I guess.

They will take about 3.1". Most have the mag blocked to 2.8'ish, but it's easy to get them to run at 3.05" or so. Perfect for the rounds you mention.

Concur with this Rick. I have a late model NH built M-70 SA CRF that had a "spacer" or block that had to be ground off - not that big a deal. This increased the box length to 3.1" and the follower works just fine. This is a perfect sized action for my 284 win and would be excellent for any x57 cartridge IMO.

I'd sure like to convert my 7mm-08 NH built M-70 SA CRF to 7X57.

I have one rebarreled to 257R. The magazine has a spacer that would be easy to remove. But there is also a bolt stop that would have to be modified to allow the bolt to travelfarther to the rear. How hard is that to "fix". thanks

Not hard. Just measure how much needs to go away, then remove the piece, grind off the amount you need (while keeping the same profile), polish off the burrs and reassemble.. The ejector will have to be shortened as well..

You can do good things with a short M70. This classic stainless 22-250 was turned into a beautiful custom 284Win by Greydog. Bansner stock, PN 23" #1 barrel. The mag was modified, and my loads were around 3.05". One of the many nice rifles I USED to own!

Wow Rick, that's exactly what I'm talking about! At first, I wanted to do a build on a military Mauser. It looked like modifications to the action are going to run me way over budget. So, my next choice is a Winchester M70.

There are Ultimate Shadows for $574 locally in 243 and 308. Figured I could part it out and re-barrel with new stock and williams bottom metal. I even though about buying a featherweight and keeping the factory stock and just re-barreling. That would be spiffy. Those are going about $100 more locally and would save me money in a stock.

Swampman,
I know a guy who could do it for you. My 284 win started out as exactly what you have. Basically, all he had to do was remove the spacer and ream the barrel. I have since added a McEdge to it I got from here. She weighs 6-6 and shoots 140 TTSX right at MOA in the 3050-3100 fps range. Couldn't be happier with how mine turned out. PM me if you are interested.
bludog

I've got a SC M70 S/A that was built into a 6.5x284. Just swap the mag box and follower out for a WSM box and follower and you're good to go. Or do as others have suggested and remover the spacer.

Can a 7mm-08 be reamed out to 7x57? Seems like the 7x57 has more of a tapered case than the 7mm-08?