Winchester M70 .338 to .416RM... possible?

Badboymelvin

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Hey guys,

I'm at home bored so I got thinking...

Could my Winchester M70 control round feed .338Win Mag be made into a .416 Remington Magnum?
I know the .338 is shorter than the .416RM but can the action and magazine be opened up, lengthened etc...?
I understand that the .416 Taylor would be easier but I've always had a thing for the .416RM...

What do you think guys... could it be done?
Has anyone here done it?

Cheers,

Russ
 
Hey guys,

I'm at home bored so I got thinking...

Could my Winchester M70 control round feed .338Win Mag be made into a .416 Remington Magnum?
I know the .338 is shorter than the .416RM but can the action and magazine be opened up, lengthened etc...?
I understand that the .416 Taylor would be easier but I've always had a thing for the .416RM...

What do you think guys... could it be done?
Has anyone here done it?

Cheers,

Russ
I’m sure it could be done as I’ve seen M70 Lott rifles for sale, but it may require quite a bit of action/magazine tuning to get the .416 Rem cartridge to feed and function reliably? My Whitworth .416 Taylor is a great shooting rifle and I can form the cases from either my .338WM or .458WM brass. But, if you must have .416 Rem go for it and I’m sure one of the experts here will have the answers your looking for. Good luck!
 
Theoretically not difficult at all. 3.34” to 3.6”. If magazine has spacer, remove spacer to accommodate 3.6” cartridge. If follower is shorter than full magnum length, best to replace with long mag follower. Winchester regular long action (30-06 length) is same length as what they use for their 3.6” magnums. Might or might not? need to tweak bolt stop and ejector for best function ( slightly shorten, reshape).
 
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Depends on the vintage of model 70. It’s a fair amount of work on a pre-64. Not worth it unless it’s butchered up to start with. On a New Haven Classic, it’s some work. I got an H&H length mag box. One could remove the spot welds that hold the spacer in the standard mag box. I had to replace the follower with a Sunny Hill to get mine to feed and use a Remington spring. I also had to machine the area behind the magazine as there is a little square of steel there that I had to remove. I had to reshape and lengthen the feed ramp. Also had to open up the back .250 of the feed rails to make room for the belt. You’ll need a H&H bolt stop and ejector and Williams extractor.
IMG_2459.jpg
The port will work as is without machining about 99% of the time on empty’s if the action is cycled smartly, 100% on loaded rounds. I would not trust it fully for DG, mine is currently a 300 H&H. I would not do it to a complete stock rifle, at least in the case of my project. It is a SS lefty (scarce) but I bought it action only from someone who was thinking of doing the same thing. I cannot speak to the new Model 70.
 
BBM,
WHY?
What animal is there in Australia that a .338 Win Mag will not kill?
 
I’m sure it could be done as I’ve seen M70 Lott rifles for sale, but it may require quite a bit of action/magazine tuning to get the .416 Rem cartridge to feed and function reliably? My Whitworth .416 Taylor is a great shooting rifle and I can form the cases from either my .338WM or .458WM brass. But, if you must have .416 Rem go for it and I’m sure one of the experts here will have the answers your looking for. Good luck!

Hey mate,

It's funny you mention that, as the .416 Taylor is the direction I think I'm going to go now.
It'll just be the easiest and cheapest route. (y)

What velocity are you getting?
Can you get 2350fps with a 400gn projectile in the Taylor?
What barrel length do you have?
I'd love to fit a 20" but not sure I'll get the desired velocity...

I've had some feedback and although I can fit a .416RM in my action, theres a bit more involved than I first thought. And there's a bit more expense than I first thought...

Cheers,

Russ
 
Depends on the vintage of model 70. It’s a fair amount of work on a pre-64. Not worth it unless it’s butchered up to start with. On a New Haven Classic, it’s some work. I got an H&H length mag box. One could remove the spot welds that hold the spacer in the standard mag box. I had to replace the follower with a Sunny Hill to get mine to feed and use a Remington spring. I also had to machine the area behind the magazine as there is a little square of steel there that I had to remove. I had to reshape and lengthen the feed ramp. Also had to open up the back .250 of the feed rails to make room for the belt. You’ll need a H&H bolt stop and ejector and Williams extractor.View attachment 415797The port will work as is without machining about 99% of the time on empty’s if the action is cycled smartly, 100% on loaded rounds. I would not trust it fully for DG, mine is currently a 300 H&H. I would not do it to a complete stock rifle, at least in the case of my project. It is a SS lefty (scarce) but I bought it action only from someone who was thinking of doing the same thing. I cannot speak to the new Model 70.

Thanks for your reply. It was very helpful (y)

Cheers,

Russ
 
Theoretically not difficult at all. 3.34” to 3.6”. If magazine has spacer, remove spacer to accommodate 3.6” cartridge. If follower is shorter than full magnum length, best to replace with long mag follower. Winchester regular long action (30-06 length) is same length as what they use for their 3.6” magnums. Might or might not? need to tweak bolt stop and ejector for best function ( slightly shorten, reshape).

Thanks for the reply mate, very helpful (y)

Cheers,

Russ
 
BBM,
WHY?
What animal is there in Australia that a .338 Win Mag will not kill?

Good question crs...

There's nothing in Australia that the .338 won't kill - but I have a Water Buffalo hunt planned next year (fingers crossed) and I would really like to use a .416 on this trip along with my .458.
I've always had a thing for the various .416's and have never owned one. As this trip will likely be the only one I can afford for a long time, I'd love to be able to use a .416 on this trip along side my .458.

It's just a bucket list thing really...

But let it be known that I love the .338WM

Cheers,

Russ
 
Are M70s in 416 hard to find?

They pop up occasionally, but I was just thinking that I already have a M70 and was wondering if I could shoehorn a .416RM into mine...
It can be done but it was a bit more expensive than I first thought...

I'd love a M70 in .416RM, it's one of my dream rifles... just unfortunately out of my price range at the moment...:cry:

Cheers,

Russ
 
Hey mate,

It's funny you mention that, as the .416 Taylor is the direction I think I'm going to go now.
It'll just be the easiest and cheapest route. (y)

What velocity are you getting?
Can you get 2350fps with a 400gn projectile in the Taylor?
What barrel length do you have?
I'd love to fit a 20" but not sure I'll get the desired velocity...

I've had some feedback and although I can fit a .416RM in my action, theres a bit more involved than I first thought. And there's a bit more expense than I first thought...

Cheers,

Russ
So far I’ve only reloaded 400gr Barnes original bullets behind 70gr of RL 15. I don’t have a chronograph but the recoil feels like a moderate load and very manageable. According to various reloading data I’ve seen, the Taylor will achieve 2400fps muzzle velocity with different powders pushing a 400gr bullet. My rifle has a 22” barrel.
 
So far I’ve only reloaded 400gr Barnes original bullets behind 70gr of RL 15. I don’t have a chronograph but the recoil feels like a moderate load and very manageable. According to various reloading data I’ve seen, the Taylor will achieve 2400fps muzzle velocity with different powders pushing a 400gr bullet. My rifle has a 22” barrel.

Thanks mate.
Yeah, I'm tossing between the .416 Taylor or the .416 Ruger. With the Ruger I can get factory ammo for it (expensive and hard to find but is available), but with the Taylor I can get components a bit cheaper - in Australia anyway...
I really like the .416 Rem Mag the most, but someone who's modified a M70 like mine to suit it has messaged me and the cost of doing it is more than I was expecting...

Cheers,

Russ
 
Hey guys,

I'm at home bored so I got thinking...

Could my Winchester M70 control round feed .338Win Mag be made into a .416 Remington Magnum?
I know the .338 is shorter than the .416RM but can the action and magazine be opened up, lengthened etc...?
I understand that the .416 Taylor would be easier but I've always had a thing for the .416RM...

What do you think guys... could it be done?
Has anyone here done it?

Cheers,

Russ
If yours is pre 64 leave it alone. Get a 416 remington. You do get 300gr woodleigh bullets for. 338.
Krish
 
Thanks mate.
Yeah, I'm tossing between the .416 Taylor or the .416 Ruger. With the Ruger I can get factory ammo for it (expensive and hard to find but is available), but with the Taylor I can get components a bit cheaper - in Australia anyway...
I really like the .416 Rem Mag the most, but someone who's modified a M70 like mine to suit it has messaged me and the cost of doing it is more than I was expecting...

Cheers,

Russ
I think the .416 Ruger is a fantastic cartridge too. The only down side is maybe the scarcity of brass and finding reloading dies? Maybe you could trade for a .416 Remington if you have your heart set on that cartridge?
 
Except for reaming, milling the extractor slot and threading the barrel which is a gunsmith job, the rest it is pretty much a DIY type project if you have minimal skills and a few shop tools. The 338 WM base and body are the same dimensions as the 416 Rem. I don’t know where the notion comes from about messing with feed rails and the ramp?? It’s 3.34” length cart to 3.6” length cart conversion. You didn’t mention pre-64, so assuming it’s not. I’d leave a pre-64 alone. The 416 Rem is a heck of a cartridge- IMO the best of the 416s. If your gunsmith can change out a Winchester barrel, I’d sure hope he could remove the spacer in the magazine box and install a long mag length follower!!
 
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BBM,
Thanks for the response.
BTW, I have taken water buff with my WINCHESTER m1895 .405 WITH 300 GRAIN North Fork cup point solid BULLETS at 2250 fps MV - my hand loads. One shot through shoulder, heart and out the off side.
Hit the ground so hard, the head bounced.
PS I HAVE WITNESSES! :)

Same rifle and ammo loaned to this hunter took this beauty after his 30-06 ran out of bullets:
55231_600x400.jpg
 
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