Currently available way to get a 4 round magazine Winchester 70 375 H&H

[MaxM25]

I have read about the Duane Weibe XRM magazine box that was available for the Winchester 70 in 375 H&H. Unfortunately, it does not seem to be available anymore. Is there anyway that is currently available to increase the magazine capacity? I read something about changing the magazine spring to one without a hump using Winchester P/N U356420930 Magazine Spring L/A; does that work? It really seems a shame that the XRM stopped being available.

 

[MaxM25]

On another forum in post 5112441 they mention specifically that there is a Winchester mag box and follower that enable 4 rounds of 375 H&H. I cannot find the thread in the Gunsmithing section of that forum.

For some reason I am not able to type the name of that forum in a post on this forum. To my surprise I just get a “Not Permitted” word replacement. I have never seen that happen on a forum before.

 

[MaxM25]

Interesting, I found a mention in post #4 on another forum of the same point. The guys say they always change the follower and spring so they can load a 4th 375 H&H round in a Winchester 70 Classic.

https://forums.**NOT**PERMITTED**.com/threads/made-some-changes-to-my-winchester-70.163158/

 

[nomspc]

I have read about the Duane Weibe XRM magazine box that was available for the Winchester 70 in 375 H&H. Unfortunately, it does not seem to be available anymore. Is there anyway that is currently available to increase the magazine capacity? I read something about changing the magazine spring to one without a hump using Winchester P/N U356420930 Magazine Spring L/A; does that work? It really seems a shame that the XRM stopped being available.

Jim Brockman, http://www.brockmansrifles.com/index.php has made a few extended Model 70 magazine floor plates for me.

 

[odonata]

I know nothing about this company or the product. I'm just sharing a link:

Sunny Hill Enterprises - 70 Winchester

 

[MaxM25]

I thought it was interesting that there is mention of a spring and follower change that can get a 4th round of 375 H&H in the magazine.

It looks like that bottom metal had an Oberndorf release. Is there anyway pro/con to that style compared to the push button on the Winchester from the factory?

 

[Philip Glass]

Whatever you decide to do just make sure that it works very well before going on a DG hunt with it. These kind of modifications scare me so just be careful.

 

[MaxM25]

Jim Brockman, http://www.brockmansrifles.com/index.php has made a few extended Model 70 magazine floor plates for me.

View attachment 647766

That is great.

 

[Ontario Hunter]

When I ordered bottom metal for my 404 build on 98 Mauser, Swift-Blackburn offered both 3+1 and "extended" 4+1. But it is my understanding that 4+1 requires custom stock. It will not drop into a standard 98 Mauser stock. I went with 3+1 because I didn't want to wait for a custom stock to be made. If I can't stop a buffalo with four rounds of 400 gr 404 Jeffery, perhaps I deserve to get stomped. Anyway, I modified the extractor to snap over on a round dropped in an empty chamber so fifth round can still be loaded quickly if needed.

 

[MaxM25]

I know nothing about this company or the product. I'm just sharing a link:

Sunny Hill Enterprises - 70 Winchester

View attachment 647768

That Model 640 bottom metal looks interesting. It seems to have an Oberndorf release. Is the Oberndorf release for the magazine an OK thing to have on a dangerous game rifle?

 

[Ontario Hunter]

That Model 640 bottom metal looks interesting. It seems to have an Oberndorf release. Is the Oberndorf release for the magazine an OK thing to have on a dangerous game rifle?

The Oberndorf style was all I could find when I was shopping for 416 Rem bottom metal when building my 404J (Sunny Hill would make 404J bottom metal for me but $700 pricetag was too much). I don't think it's that big an issue if the release is stiff enough. Some makers sell them with adjustable release. Mine from Swift-Blackburn required some fine tuning. Any hunter holding a 375 so loosely that his finger hits the release during firing will probably have other issues to worry about. Like scope or thumb hitting him in the face. I don't see accidentally releasing the floorplate being much concern if you spend some time learning to shoot your gun.

Again, note that the magazine box is deeper on NECG Model 640. It will hang below your current stock. If the floorplate is wider than the magazine, and most are to conceal the contact area around the magazine box, then that would be a problem for you. Besides being unsightly, the exposed floorplate overhang could get caught on stuff. It is hard to tell from the photo if the edge of floorplate is flush to the sides of magazine but I seriously doubt it. If not, then a custom stock with deeper mag well would be required.

 

[odonata]

I cannot give you an opinion based on in-field experience because I've never been DG hunting. Any reply I give will be based totally on intuition.

Whenever I look at classic African rifles at places like Griffin & Howe or Westley Richards, this type of release is often seen on the bottom metal. There is currently an active thread on building a large 50 caliber rifle where pictures of the Weibe bottom metal shows that it uses this type of release as well. The main thing you would want the release to do is not move under heavy recoil and spill all of your backup rounds of ammo all over the dirt while you have something big & irritated heading directly for you. As mentioned above, the strength of the spring release being stiff enough is the main factor.

Compared to other "inside the bow" releases I've seen, this one looks similar & pretty substantial. But how it works & fits is unknown to me:

My expertise is mainly on how to use Google well to find stuff not rifle building.

 

[MaxM25]

The Oberndorf style was all I could find when I was shopping for 416 Rem bottom metal when building my 404J (Sunny Hill would make 404J bottom metal for me but $700 pricetag was too much). I don't think it's that big an issue if the release is stiff enough. Some makers sell them with adjustable release. Mine from Swift-Blackburn required some fine tuning. Any hunter holding a 375 so loosely that his finger hits the release during firing will probably have other issues to worry about. Like scope or thumb hitting him in the face. I don't see accidentally releasing the floorplate being much concern if you spend some time learning to shoot your gun.

Again, note that the magazine box is deeper on NECG Model 640. It will hang below your current stock. If the floorplate is wider than the magazine, and most are to conceal the contact area around the magazine box, then that would be a problem for you. Besides being unsightly, the exposed floorplate overhang could get caught on stuff. It is hard to tell from the photo if the edge of floorplate is flush to the sides of magazine but I seriously doubt it. If not, then a custom stock with deeper mag well would be required.

Yes, it seems the McMillan Safari stock is setup for this dropped magazine Sunnyhill.

https://mcmillanusa.com/shop/browse-mcmillan-rifle-stock-models/flat-top-only-stock-models/winchester-safari-flat-top/

 

[MaxM25]

It would be perfect to get a Duane Weibe XRM magazine box that allows an extra round in a Winchester. It is unfortunate that he stopped making them.

 

[Challer]

I used the Sunny Hill model 70 McMillan setup with great success

 

[Ontario Hunter]

You should explore the modified follower and spring method further. Very intriguing. Sounds like something a good machinist would be able to tackle.

 

[Ontario Hunter]

I used the Sunny Hill model 70 McMillan setup with great success

Can you supply a photo? I'm curious, does the magazine extend below the stock?

 

[Jack Stevens]

The magazine of my old BRNO 602, a Lon Paul custom, can hold six (6) .375 rounds, although typically I run it 5+1 so as not to stress the mag spring.

 

[cajunchefray]

That Model 640 bottom metal looks interesting. It seems to have an Oberndorf release. Is the Oberndorf release for the magazine an OK thing to have on a dangerous game rifle?

Do you have a Pre-64 made Model 70, or a post 1994 Model 70?

The Sunny Hill model 640 is for the Models 70s built prior to 1964, and the bottom metal, as pictured, is one piece magazine box and floorplate, a la Mauser 98.

The post 1994 made guns (marked "Classic" on the barrel), utilize a separate magazine box from the floorplate.

The Sunny Hill model 740 is correct for this. Personally, I prefer the classic look of the Oberndorf floorplate release. I have a Williams made floorplate on my M70 Classic 30-06, Oberndorf release and have had no problems.

Personally, I would not just change the follower and magazine spring to get a 4th round. The geometry of the follower, spring and mag box are designed to insure proper feeding. Not a chance I am willing to take.

I bought a recent production, used M70 Alaskan, 375 H&H for an (almost) too good to be true price on GB. It would not feed the 2nd and 3rd round worth a damn. I removed the bottom metal and found that the magazine spring was slightly kinked, out of alignment. A new spring from Winchester, of proper dimension, and it feeds perfectly.

 

[Challer]

Can you supply a photo? I'm curious, does the magazine extend below the stock?

Slightly. Now sold I went to the dark side of the R8