Winchester m70 feed issues

[Hammockhead]

So ai bought a customized m70 from a friend. The barrel was chambered to fit very long 7mag bullets. Well the box mag was modified to fit said bullets. Now the bolt doesn't actually slide back far enough to clear the rim of the case, so it won't feed the bullets. Also (and not sure it was the original box mag), the mag won't hold more than 2 cases with spitting them all out. So, I have heard that you can modify the bolt or something to function with the longer rounds. Something about what is done for those that shoot a 300h&h. So I need to fix the bolt issue. But I also need advice on how to fix the mag issue. Does anyone know the markings on an original 7mag box mag insert?

 

[swehrman]

Is the action a push feed or controlled round feed (CRF)? The magazines are different for the two action styles.

-- Scott

 

[Hammockhead]

It's a push feed. Hinged floor plate. If that matters

 

[ODB]

If you look in your mag box, you probably won’t see a block at the back. If that’s the case, the bolt stop is probably too long because it’s for a standard magnum, not a 300/375 length, which is what it will be if you remove the block. Then there are the feed lips of the box...did those get tweaked? If the rifle does not retain the rounds, it sounds like there is not enough round tucked up under the rails. That’s a much harder issue to fix.

feeding is never a single-answer problem. I spent 3 days with my friend Darcy Echols working on a Mauser. There is an awful lot going on in what seems to be a simple operation. And most of it you can’t see...

 

[Hammockhead]

So how does one fix the bolt stop issue? We actually tried 4 different mag boxes that he had laying around. Some with the spacer box in the back, some without. Tried loaded rounds, empty casings. It will hold 2 rounds, more than that and it just spits them out. Some of the boxes had the lips tweaked from times past, some did not.

 

[Wrench]

Cycle the bolt all the way back. You can tell a lot by the relationship of the bolt face to the rear if the mag.

The very last thing you want to do is start removing metal from the bolt or feed rails.

You will most likely have some reshaping of the mag box lips, spring and follower.

Here is a link to Wyatts box for the m70 which explains some of the work required to make the mag box sit closer to the rear.

MBE-08 Magazine Box - Wyatt's Outdoors

This box is designed for the Win. M-70 Long Action. It incorporates windows for the larger diameter cases, or may also be used for the std. cases. This box allows for an O.A.L. of approx. 3.825″. The receiver, bolt stop, and ejector, must be altered to use this box. Outside length is 3.910″...

wyattsoutdoor.com

You have a response in your thread from a person who has watched Echols work.....that's valuable. If you are not familiar with Darcy's work....it's worth reading about.

 

[ODB]

Cycle the bolt all the way back. You can tell a lot by the relationship of the bolt face to the rear if the mag.

The very last thing you want to do is start removing metal from the bolt or feed rails.

You will most likely have some reshaping of the mag box lips, spring and follower.

Here is a link to Wyatts box for the m70 which explains some of the work required to make the mag box sit closer to the rear.

MBE-08 Magazine Box - Wyatt's Outdoors

This box is designed for the Win. M-70 Long Action. It incorporates windows for the larger diameter cases, or may also be used for the std. cases. This box allows for an O.A.L. of approx. 3.825″. The receiver, bolt stop, and ejector, must be altered to use this box. Outside length is 3.910″...

wyattsoutdoor.com

You have a response in your thread from a person who has watched Echols work.....that's valuable. If you are not familiar with Darcy's work....it's worth reading about.

if you’ve got some time, you can read all about my Mauser feeding lesson from Darcy right here:

(Complete Report and Pics 3/11!) Two Days with D'Arcy Echols - Making a Mauser Feed - Topic

forums.accuratereloading.com

 

[swehrman]

So how does one fix the bolt stop issue? We actually tried 4 different mag boxes that he had laying around. Some with the spacer box in the back, some without. Tried loaded rounds, empty casings. It will hold 2 rounds, more than that and it just spits them out. Some of the boxes had the lips tweaked from times past, some did not.

What are the four markings on the magazines that you did try? It turns out Winchester used quite a few different markings over the years. I found C, BR, BF, H, and K.

-- Scott

 

[Hammockhead]

Thank you guys. It will be a short bit before I get to reading that and checking mag markings. But appreciate the quick responses.

 

[fraz01]

Midwest Gun Works has a good schematic on the model 70, as well all the different parts used for different calibers. Think the magnum mag box (375H&H / 300 WBY) is 3.6 inch coal.

 

[Marble]

This wont fix your current issue without the barrel being pulled, rebored and installed. Or maybe not at all. But when I had my barrel done, I asked them to set the throat shallow enough so I could seat a berger 180 up to the lands, without having to do the box. It worked, barely, but they succeeded.

 

[ODB]

Forgetting the retention issue for a sec, when you have the bolt all the way back, depress the bolt release and scoot the bolt back a little more (but don’t remove it)to catch the rim. Does it pick Up the rim properly and feed, or is the ass-end of the round still too low? If the rounds are not stacked properly in the box, they will not travel up the box smoothly. If the ass-end is low, it could be the spring too. Take the spring and follower out and with the follower level, push down slowly On a table. Does the ass end or front end dip? It could be an uneven spring.

unlike the pre-64s, newer Winchesters rely on the mag box lips to feed,
not really the rails. Did anyone goof with the rails?

in my long story above the lesson is at the very end of the video - we just followed the rules. If you’ve got a hodgepodge of parts, the very first thing I would do is forget about the long OAL 7mag for a minute, put in the proper box/ follower ( if they used a 375 length box, they may have tossed in a 375 length model70 follow, which is a skosh longer)for a standard 7mag and see what happens. In the case of my 9.3, we didn’t actually change anything away from standard, we used Mausers rules and applied them. The same can be said in your case, you just have to find where you are and where you need to be. keep this in mind, when I handed my rifle to Darcy, before he even ran a single round to check feeding, we took the rifle apart to find out “ where it was” geometrically.

then again, if you bought this from a friend, he Must have also had these problems, no?. else what changed between him having it and you?

undertand here too, my advice isn’t really to provide a solution, just to help you identify what is really going on. And I’m not trying to over complicate this, but as a dude who has spent an awful lot of time and money on getting a rifle to feed, it has changed the way I even start to look at these issues.

 

[Wrench]

Exactly. You'll be very surprised how little movement in one of the box lips can make a mess.

What part of the country do you live in? I'm no Echols but I have built enough rifles that feed odd cartridges to help you get the problem solved.

 

[Hammockhead]

I am in Billings Montana

 

[Wrench]

Sorry....I'm 496 miles west.

 

[Hammockhead]

So, finally able to get some photos. The mag that's in it is marked KF(its not modified). I have a bag of other mags, different markings, some modified, some had lips messed with all from other rifles. So I dont know which one is made to fit a 7 mag. None seemed to feed right though.
Does anyone know what the original markings are for a push feed 7mag model 70 box mag?

 

[Hammockhead]

Other mags tried were K, B and modified ML. What's weird is they seem to stack fine in my m70 280. I swapped the B mag from my 280 and also tried it with the follower from my 280 with no success.

 

[Hammockhead]

Baxterb, thanks for your responses. No, no one has goofed with the rails, the look untouched. Also, the spring seems to compress evenly. Also, the butt end does not seem low, the bolt will pick up the brass. And yeah, I have set aside the idea of the long OAL, and am using empty brass to test them. Once they stack right all have to find dummie round to test feeding of course.

 

[Hammockhead]

Sorry, I know I am rambling now. So, even though the rails (assuming that's the right term for what I am seeing) show no signs of been altered, or filed, when I compared them to my 280, they definitely aren't as wide, so the gap between the two is larger, and I am guessing that must be the issue, as that's the only variable from me taking my working box and follower from my 280 and having not work in the 7mag action. Even though I know it was stated earlier that post 64 was ran of the follower not the rail?

 

[ODB]

KF is for 270/30-06.

pretty sure you’ll need an H or ML. That’s provided nothing else is goofy.