Anyone built .375 or .416 Ruger on a Model 70

[Stompbox]

I have started building a few .375 and .416 Ruger rifles for a couple of friends and myself. All of them are going to be on Model 70 classic actions that were originally .300 Win mag or .338 win mag. I got the first .416 threaded and chambered and then test fired. The belted magnum magazine box and or the follower are not working well for retaining and feeding the Ruger cartridges. Wondering if anyone has experimented with different magazine components and had success.

 

[Inline6]

Talk to Waytt, they specialize in the box and followers game. He is a nice guy and can probably help you out.

 

[RStien321]

This is one of the things that prevented me from going with a 375 Ruger when I was looking at building a mid-bore on a M70 platform was magazine - the shoulder is so far forward on the 375 Ruger and the straighter taper of the cartridge is much different than the magazine boxes currently out there are designed for.

Please keep us informed on what you learn - for me, a custom 375 Ruger on an M70 would be a perfect combo in my mind!

 

[cajunchefray]

I have started building a few .375 and .416 Ruger rifles for a couple of friends and myself. All of them are going to be on Model 70 classic actions that were originally .300 Win mag or .338 win mag. I got the first .416 threaded and chambered and then test fired. The belted magnum magazine box and or the follower are not working well for retaining and feeding the Ruger cartridges. Wondering if anyone has experimented with different magazine components and had success.

I was thinking of exactly this last night. Would really like both a 375, first then a 416 Ruger.

As I understand, the magazine box controls the feeding in the post-64 Classic. The magazine in my 7x57 Classic is formed sheet metal.
Easier to modify than forged steel.

I wonder if the Paul Mauser cosine formula would work in reforming the magazine box?

 

[Nhoro]

As I understand, the follower effects the last round feeding. Generally the feed lips of the reciever and the stack angles of the cartridge + diameter of cartridge control the rest. A bigger diameter cartridge will need a wider magazine box to stop from popping up. You can use the mauser formula to get the width. Or just take out the metal magazine box and see if the wood of the stock gives you better feeding.

 

[Muskox]

Unless you just have to have one. I think a M70 would work better in a 375 H&H.

 

[dcecil0011]

I have started building a few .375 and .416 Ruger rifles for a couple of friends and myself. All of them are going to be on Model 70 classic actions that were originally .300 Win mag or .338 win mag. I got the first .416 threaded and chambered and then test fired. The belted magnum magazine box and or the follower are not working well for retaining and feeding the Ruger cartridges. Wondering if anyone has experimented with different magazine components and had success.

Did you have any success getting this to work? If so, what parts did you use?

 

[Stompbox]

I just recently got a chance to get back on the first.416 Ruger build. I finally got my extractor cutter from PTG and got the extractor cut in and I have purchased quite a few of the different magazine boxes and followers that Winchester used in a variety of their model 70 rifles. It’s unreal how many variations are actually are. I have played around with different magazine boxes, followers, and springs and ended up also modifying the magazine box, but my latest test show that the rounds sit properly in the magazine and feed and eject perfectly. I have everything disassembled again to do some more work and I’m waiting for a barrel band and the sights. Once I get this completed, I will put together a list of the components I used and try to show the modification to the magazine. It’ll end up being fairly easy and similar to what Winchester had to do on the magazine boxes with the WSM cartridges or what they did with the .300 Remington ultra mag models.

 

[Ontario Hunter]

Am I understanding this correctly that there are essentially no feeding rails in receiver of Classic and that the magazine box controls the feeding? Unless this is true (which seems doubtful), I cannot see how changing the box alone will give reliable feeding for cartridges that are so radically different from the donor rifle's cartridge. The rails in the receiver will also need to be modified.

During my 404 build on 98 Mauser I learned the Paul Mauser 30° formulis for magazine dimensions is not carved in stone. I used 416 Rem bottom metal which is narrower at the shoulder than 404 and it worked fine without modification.

I reshaped my follower to make it work. I didn't have the option of hunting up different caliber followers and trying them. Interesting idea.

 

[Stompbox]

The model 70 has feed rails built into the receiver. But, they also have magazine boxes that have different shapes at the top that can influence the cartridges feeding. Sometimes the thickness of the material that the box is made out of can also influence how those cartridges sit in the magazine. I’m using a receiver that was designed for a belted magnum cartridge and the Ruger cartridges have the same diameter at the base as a belted magnum, so there is room in that portion of the magazine. The shoulder, however, is a larger diameter on the Ruger cartridges than most of the belted magnums, and they get jammed together towards the front of the magazine box. Removing material from the proper location in the magazine box can allow the shoulder area of the cartridges enough room for the cartridges lay properly on each other. If you look at what Winchester did on the WSM and the ultra Mag model 70 magazines, you can see the modifications they made to get those cartridges to feed. Winchester has made a lot of different magazine boxes and followers for the model 70s over the years so they work proper or specific cartridges. I’ve had seven or eight different model 70s in .375 H&H and I know there were at least four different followers among those rifles.
If you browse through Midwest gun works or Numrich, you can see all variations of magazine boxes, followers and springs that Winchester has used, and I have bought practically every variation I could get my hands on and tried several different combinations in messing with these Ruger cartridges. My current set up gets three cartridges in the magazine with enough room for the bolt to slide over them without being tight.

A couple years ago I messed around with trying to make a 375 Ruger on a large ring Mauser and just wasn’t happy with the results I was getting.

 

[Stompbox]

I found some pictures that I took about six months ago that shows some cartridges sitting in a standard model 70 magazine box that has straight walls from bottom to top and then you can see a picture of the cartridges sitting in a gun that has a modified magazine box and you can see how well the cartridges stack in comparison to the unmodified magazine box.

 

[Ontario Hunter]

To be clear, building my 404 on 98 Mauser 8mm required modifying the feeding rails, loading ramp, follower, bolt face, and extractor. No shortcuts. I had Paul Mauser's cosine 30° formula in hand before approaching the project so I knew what the correct magazine dimensions  should be when ordering bottom metal (trigger guard/magazine box assembly). Since no one had the bottom metal for 404 on hand, I knew I would have to find something available that I could modify. Blackburn kindly sent me blueprints of several caliber bottom metal they were set up to make and I selected 416 Rem as closest to the formula specs. Like your project, I knew going in the shoulder of 404 was wider than 416 Rem, but not much wider. Figured there would be enough metal in the sides of the box to allow me to carve out what was needed to comply with Paul Mauser. Turns out I didn't have to make any modification ... to the box. But the rails and ramp still required significant modification. A very laborious process!

I am concerned that you somehow were able to avoid modifying the receiver rails for a cartridge significantly different from the donor rifle, especially in the shoulder region. You say it is cycling the rounds. What does the brass look like after cycling? Any scratches or dents?

If you had used Mauser's formula, you could have calculated what you needed for dimensions before purchasing a bunch of boxes for trial and error. Not practical for me because the cost of custom bottom metal was +$400.

Why was your attempted 375 build on 98 Mauser unsatisfactory? What problems?

 

[Stompbox]

Please Don’t Hijack!
Before this turns into another AH 19 page back-and-forth, I’m going to politely as I can, and with as little humor and sarcasm as I’m capable of, ask you to not hijack this thread. This thread is for .375 and .416 Ruger cartridges in a model 70 action. I’ve been on this forum awhile and read enough threads to know that I can’t hardly find one that you haven’t commented on, you seem to have a deep seated need to be heard. Maybe you are full of that much knowledge, I don’t know.

What I do know is that I’m getting old, and short on patience. I graduated from high school in the mid 80s and did a two year technical school for machining and have worked in the machining trades as a tool maker for most of the time since then, mostly in the computer and medical fields . I also went back to a technical college and have a two year associates degree in gunsmithing and have spent time as an adjunct instructor for advanced machining and barreling and chambering classes.

This is far from being my first rifle build, I’ve built rifles using pre-64 model 70 actions, model 70 classics and model 70 push feeds. Large ring and small ring mausers, both commercial and military. Remington 700, Tikka’s, CZ’s, savages and Ruger’s.

This is specifically about issues with model 70s in those two calibers, only.
I didn’t go to your 404 Jeffrey thread and talk about the 1/7” twist .22–250 Ackley that I built on a long action 700 and what I had to go through to get everything to work, because it doesn’t apply. While there are similarities between all both action rifles, a model 70 and model 98 are not the same, parts are not interchangeable.

I know about the Mauser calculation, and I even had something laid out in solid works, but I didn’t have all the different dimensions of the various magazine boxes and followers that Winchester made, so I bought as many as I could. Why, because I can, and because I like to put together different combinations of parts and see how they actually work, not how the theoretically work.

I don’t know why you would be overly concerned that I didn’t have to machine the feed rails? The combination I have at this time feeds smoothly both while working the bolt slow or working it fast and when I get everything back together, I can post a video so that you’ll be able to sleep at night.

Sorry everybody, but I don’t like condescending questions from someone without experience doing specifically what I’m trying to accomplish and taking things off track from what the thread is supposed to be about.

I know if things aren’t kept on track, they go wild. You sometimes have to get through 6 pages of GLWS in the classifieds to get the info you want.

 

[Ontario Hunter]

Take it easy. Read back through your posts. It didn't appear that you were very knowledgeable. And I was not the only one misled. The questions and info supplied were sufficiently vague for us to make incorrect assumptions. I felt it might be helpful to pass along a few things I learned the hard way during my build even if it was not the same caliber. Principles and technique are the same. You're welcome. Did not intend to be condescending.

Glad you have resolved the issue. Just curious, was the box machined or stamped metal?

 

[Grumpy gumpy]

Not being that familiar with the internals of a m70, how wide did the mag box end up being, and are you using a composite or wood stock. I’m trying to decide whether to remove mag walls and rebuild them on a Mauser and I’m looking at various options in design of mag wells and I’d had m70 mag box suggested to me so your build is of interest. I’m also using a wood stock
Hope this is ok question and not meant as a thread drift
Gumpy

 

[Stompbox]

I am using one of the factory Winchester magazine boxes, that I have modified to provide more room for the shoulder of the cartridges. At this time, it seems to work well, but it is still in development/prototyping stages. If you look at what Winchester did For the WSM and the ultra mag magazine boxes, where they cut a window into each side of the magazine box,I am doing a similar thing. You have to remove material so that there’s room for the shoulder. I am using woods stocks currently.

I am gone from home a lot for work, so the time I have to work on this is limited and when I’m gone, I don’t have access to the parts that are sitting at home. When I get some more work done on the barrel and receiver and get my sights brazed on I will put it back together and compile a list of what I used. I wish I could remember offhand which magazine box and follower gave the best results, but I don’t remember at this time. I know that I got on a couple of sites and bought a half a dozen more of each for future builds while they were available. I ended up modifying the magazine box a little at a time until I got the results that I needed and once I’m completely satisfied, I’m gonna check with having them modified with either laser cutting or possibly wire EDM , the one I have right now looks a little crude
because it’s been cut and filed and Dremeled a little at a time to make the proper clearance.