Gunsmithing M70 How To !

wapiti16b

Sergeant
Full Member
Minuteman
Mar 16, 2014
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New Mexico
What is the best way to get the longest coal out of a WIN M70SA ?
What magazines and what bottom metal?
How do I get more coal over the 2.890 I'm limited to with my FNH TBM for reliable feeding ?
I'd really like to go double stack like the FN mags and the ARC mags look promising but I cannot find any information about mag BM compatability with the WIN SA .
I'd really like to do a long free bore 7SAW build off this action if it is within my budget .
Help!
 
Only option is a CDI bottom metal that takes AICS magazines. Receiver will need to be modified for the AICS magazines to work.

You'll get 2.980 or there about from an AICS type magazine w/o the front binder plate.
 
You have 2 choices:

1) CDI as stated above

2) PTG: http://pacifictoolandgauge.com/524-winchester-detach-mag-bottom-metal-dbm

With that said, I have two with the CDI and one with PTG dbm.
I prefer the CDI but that is my opinion.

The receiver mod is easily accomplished and the benefit is well worth the effort.

DO NOT listen to the M70 DBM haters as I am sure they will arrive shortly. Spewing the word about
how this mod will void your lifetime warranty, all of the structural strength in your receiver will be gone,
AICS mags aren't that good and the factory FN mags feed like melted butter etc.

Good Luck!
 
CDI offers receiver mod, need to open front of magazine cut out in receiver so the AICS mag has enough room to fit.
I left a Win 70 SA as a hinged floor plate, able to make a few mods to allow OAL of 3.030". Lets a 260 really shine with longer bullet.
 
I have a Winchester Laredo (1994 version) with the CDI bottom metal along with a Matters T5 adjustable stock. There was NO Milling done to my action only had to modify the magazines to get everything to function correctly. What I had to do was notch the front part of the magazine and also shorten the feed lips the same amount that I took off for the notch up front. By using some dummy rounds that were put together to create the OAL of the cartridge (300WM) I reload. I was able to get everything working without having to cut any metal from my action.

Currently I have another Laredo in 7MM Mag that I plane to do the same setup.
 
If 5 round AE mags work ok for you the oal is longer on them than a aics w/binder plate. PTG makes a drop in bottom metal that works with the AE MK 1 mag for stocks inletted for factory bottom metal. If you need greater than 5 rounds the CDI with aics mags w/o binder plates and with reciever modification is the ticket. 7wsm would definitely be a aics/cdi proposition.
 
CDI does the receiver and stock inlet for included in the $209 bottom metal price. You cannot go wrong with that and Jeff is great to deal with.

The non-binder plate AICS mags I have are all around 2.960-2.970 internally
 
I’m gunning CDI with alpha mags on my SPR in 260ai. The only reason I went away from the tbm was because the AI was too wide in the shoulder area. I never felt lacking on the mag internal length though