The Accurate Reloading Forums
Mauser 98 to .375 H&H
11 April 2011, 07:45
vapodogMauser 98 to .375 H&H
for those that have done it.
I have several VZ-24 actions and want to turn them into .375 H&H rifles.
What is the preferred way to lengthen the capability of that action to feed the longer case? I'm not concerned with the bottom metal right now....just opening the action.
I'm not wanting to cut them and weld back together but to machine from the front and back if that is what is the recommended procedure.
I do plan on re heat treating the action afterward.
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"Socialism is a philosophy of failure, the creed of ignorance, and the gospel of envy, its inherent virtue is the equal sharing of misery."
Winston Churchill
11 April 2011, 08:00
Toomany ToolsAction is opened up to the front--I seem to remember it's about .300". Simple and effective it's been done for close to a hundred years.
John Farner
If you haven't, please join the NRA!
11 April 2011, 09:10
ramrod340I have not opened one. But simply looking at the MKX 375 the rear panel of the magazine is thinned down as much as possible. The rest is length increase is in the front.
As usual just my $.02
Paul K
12 April 2011, 01:39
Don MarkeyEasiest, thin the rear and open the front. Especailly if you are using original bottom metal. But if you are replacing the bottom metal, they generally are moved more towards the rear so I would get the new mag box first.
Don
13 April 2011, 04:16
vapodogquote:
Originally posted by 22WRF:
Vapodog
if you are going to use one of those actions to make a really nice one for your own personal use
(nice wood, etc.) then you should buy this Blackburn #18 bottom metal that I have. Its for the .375 H & H. What you would want to do is get it and then fit the action to the bottom metal. But then you knew that.
$380 shipped.
That thing is absolutely beautiful and it's terribly tempting.....
I just dropped $19,500 for a new shop, $9,200 for a new well and (it goes on and on) and I just have to start restraining my checkbook....
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"Socialism is a philosophy of failure, the creed of ignorance, and the gospel of envy, its inherent virtue is the equal sharing of misery."
Winston Churchill
13 April 2011, 05:13
JBrownquote:
Originally posted by vapodog:
That thing is absolutely beautiful and it's terribly tempting.....
I just dropped $19,500 for a new shop, $9,200 for a new well and (it goes on and on) and I just have to start restraining my checkbook....
So what's another +-$400?

Jason
"You're not hard-core, unless you live hard-core."
_______________________
Hunting in Africa is an adventure. The number of variables involved preclude the possibility of a perfect hunt. Some problems will arise. How you decide to handle them will determine how much you enjoy your hunt.
Just tell yourself, "it's all part of the adventure." Remember, if Robert Ruark had gotten upset every time problems with Harry
Selby's flat bed truck delayed the safari, Horn of the Hunter would have read like an indictment of Selby. But Ruark rolled with the punches, poured some gin, and enjoyed the adventure.
-Jason Brown
13 April 2011, 05:17
Joel/AKLast year John built my 375H&H on a VZ and its a tack driver. I'd say he knows what he's talking about.
Thanks John, damn thing is beautiful.
A lesson in irony
The Food Stamp Program, administered by the U.S. Department of Agriculture, is proud to be distributing this year the greatest amount of free Meals and Food Stamps ever, to 46 million people.
Meanwhile, the National Park Service, administered by the U.S. Department of the Interior, asks us... "Please Do Not Feed the Animals." Their stated reason for the policy is because "The animals will grow dependent on handouts and will not learn to take care of themselves."
Thus ends today's lesson in irony.
13 April 2011, 05:29
Rub Linequote:
Originally posted by JBrown:
quote:
Originally posted by vapodog:
That thing is absolutely beautiful and it's terribly tempting.....
I just dropped $19,500 for a new shop, $9,200 for a new well and (it goes on and on) and I just have to start restraining my checkbook....
So what's another +-$400?
Yeah, why stop now?
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Do not answer a fool according to his folly, or you yourself will be just like him. Proverbs 26-4
National Rifle Association Life Member
13 April 2011, 06:32
vapodog
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"Socialism is a philosophy of failure, the creed of ignorance, and the gospel of envy, its inherent virtue is the equal sharing of misery."
Winston Churchill
My own, buit in 1926 and it definitely did not cost $19,500 or $9,200 then or now

WJ Jeffery in 375 H&H on standard Mauser action built in 1926
Feeds and functions flawlessly, guess those old gunmakers were definitely one up on many modern gunmakers including some factory offerings that are prone to feeding flaws !
The cartridge is a genuine Cordite Loaded Kynoch of the time with a 300 gr bullet...... guess where Winchester got their Silvertips idea from this one just has a copper cap.
13 April 2011, 07:25
Toomany Toolsquote:
Originally posted by Joel/AK:
Last year John built my 375H&H on a VZ and its a tack driver. I'd say he knows what he's talking about.
Thanks John, damn thing is beautiful.
Shhhhh! Keep it a secret; I have too much work as it is.

John Farner
If you haven't, please join the NRA!
13 April 2011, 14:40
vapodogquote:
I'll post one here for inspiration.
Inspiration to bankruptcy I'd say.....more beautiful stuff......
I think Tiger Woods thought the same thing!

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"Socialism is a philosophy of failure, the creed of ignorance, and the gospel of envy, its inherent virtue is the equal sharing of misery."
Winston Churchill
13 April 2011, 19:14
ForrestBVDog,
Think long and hard about getting the bottom metal first and opening the action to fit the mag box. Opening actions without having the bottom metal is a surefire way to build paperweights.
There's not enough room forward of the bolt stop to open only (or even mostly) to the rear. I don't know where or how that old wives' tale got started. Take the bolt out of your action and drop in a loaded 375 H&H cartridge. Slide it around and you'll see what I'm talking about.
______________________________
"Truth is the daughter of time."
Francis Bacon
13 April 2011, 21:41
JBrownquote:
Originally posted by ForrestB:
There's not enough room forward of the bolt stop to open only (or even mostly) to the rear. I don't know where or how that old wives' tale got started. Take the bolt out of your action and drop in a loaded 375 H&H cartridge. Slide it around and you'll see what I'm talking about.
Ray Atkinson used to talk about "opening them to the rear only" for 375 conversions, and I think this has just taken on a life of its own.
I have measured Blackburn, Wisner and Wiebe long magnum bottom-metal and all require about twice as much metal to be removed from the front than from the rear. Going from memory, they all require about .125" to be removed from the front and about .60" to be removed from the rear. Keep in mind my measurements are not exact and will vary for different M98 actions(I think I used an FN commercial action in 30-06 as a baseline).
Jason
"You're not hard-core, unless you live hard-core."
_______________________
Hunting in Africa is an adventure. The number of variables involved preclude the possibility of a perfect hunt. Some problems will arise. How you decide to handle them will determine how much you enjoy your hunt.
Just tell yourself, "it's all part of the adventure." Remember, if Robert Ruark had gotten upset every time problems with Harry
Selby's flat bed truck delayed the safari, Horn of the Hunter would have read like an indictment of Selby. But Ruark rolled with the punches, poured some gin, and enjoyed the adventure.
-Jason Brown
13 April 2011, 22:26
vapodogquote:
Originally posted by ForrestB:
VDog,
Think long and hard about getting the bottom metal first and opening the action to fit the mag box. Opening actions without having the bottom metal is a surefire way to build paperweights.
Thank you for that as it instantly is recognized as excellent advice!
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"Socialism is a philosophy of failure, the creed of ignorance, and the gospel of envy, its inherent virtue is the equal sharing of misery."
Winston Churchill
13 April 2011, 22:26
ramrod340quote:
about .60"
I think your number is off.

As usual just my $.02
Paul K
13 April 2011, 22:28
vapodogquote:
Originally posted by ramrod340:
quote:
about .60"
I think your number if off.
I'm sure it was meant to be .060 or a 1/16" inch!
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"Socialism is a philosophy of failure, the creed of ignorance, and the gospel of envy, its inherent virtue is the equal sharing of misery."
Winston Churchill
13 April 2011, 22:29
Duane WiebeThat .060 is pretty optomistic,,,anything over .040 will reguire a new bolt stop and ejector modifications
13 April 2011, 22:50
vapodogquote:
Originally posted by Duane Wiebe:
That .060 is pretty optomistic,,,anything over .040 will reguire a new bolt stop and ejector modifications
Thanks for the further advice....It's appreciated.
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"Socialism is a philosophy of failure, the creed of ignorance, and the gospel of envy, its inherent virtue is the equal sharing of misery."
Winston Churchill
14 April 2011, 03:43
JBrownquote:
Originally posted by Duane Wiebe:
That .060 is pretty optomistic,,,anything over .040 will reguire a new bolt stop and ejector modifications
Yes guys, I did mean .060"(not .60").
Also, Jim Wisner also told me that his bottom-metal was designed to open things to the rear and would require about .040 to be removed form the bolt stop.
Jason
"You're not hard-core, unless you live hard-core."
_______________________
Hunting in Africa is an adventure. The number of variables involved preclude the possibility of a perfect hunt. Some problems will arise. How you decide to handle them will determine how much you enjoy your hunt.
Just tell yourself, "it's all part of the adventure." Remember, if Robert Ruark had gotten upset every time problems with Harry
Selby's flat bed truck delayed the safari, Horn of the Hunter would have read like an indictment of Selby. But Ruark rolled with the punches, poured some gin, and enjoyed the adventure.
-Jason Brown
14 April 2011, 04:37
Don MarkeyVapodog, I think I still have a fn 375 guard (not hinged) around here somewere. If you are interested in borrowing for dimension to convert your one, let me know and I'll dig it out.
Don
14 April 2011, 06:28
vapodogThanks Don....that's a very generous offer and I just might accept.....
In retrospect now I'm actually thinking about a blind magazine and that isn't at all a tough one to figure out after the comments about no more than .040 additional clearance to the rear.....The rest is finding the COAL (apparently 3.600) and removing the balance from the front.
I'm not into drop boxes as this is not to be a DG gun....more a big game rifle and dedicated to shooting something in the 250 to 260 grain range.
///////////////////////////////////////////////////////////////////////////
"Socialism is a philosophy of failure, the creed of ignorance, and the gospel of envy, its inherent virtue is the equal sharing of misery."
Winston Churchill
quote:
Action is opened up to the front--I seem to remember it's about .300". Simple and effective it's been done for close to a hundred years.
and long before that 100yrs transpired , some realised the good sense in creating an true dedicated magnum length M98 receiver for the long magnums.
The earliest dated Oberndorf magnum mauser action im aware of is 1904, ..with the .375h&h being released 1912.
Mauser did things correctly, creating receivers dedicated to the length of cartridge; Kurz,Intermediate, Std. and Magnum lengths.
14 April 2011, 19:51
22WRFquote:
Originally posted by Joel/AK:
Last year John built my 375H&H on a VZ and its a tack driver. I'd say he knows what he's talking about.
Thanks John, damn thing is beautiful.
Do you have any photos of it to show?
14 April 2011, 22:07
Jim KobeYeah...we need pictures for our files. Yeah..
Jim Kobe
10841 Oxborough Ave So
Bloomington MN 55437
952.884.6031
Professional member American Custom Gunmakers Guild
15 April 2011, 05:22
BarstoolerMust want an H&H awful bad. Why not open the bolt face and rebarrel to a 375 Ruger. Much simpler, no belt, and 100 to 150 fps velocity advantage (if you want it).
Barstooler
quote:
Originally posted by Barstooler:
Must want an H&H awful bad. Why not open the bolt face and rebarrel to a 375 Ruger. Much simpler, no belt, and 100 to 150 fps velocity advantage (if you want it).
Barstooler
Why, when you can build what you want? I'm sure if he wanted a .375 Ruger he'd buy a Ruger.
Aut vincere aut mori
17 April 2011, 09:59
Joel/AKI was looking for a utilitarian 375H&H. Nothing fancy but something that works.
John put this together for me. with the irons I shot a .8" 3 shot group at 50 yards (off the bench). I had it black nitrided and it currently sits in a plastic stock. to some it maybe ugly but I like it.
A lesson in irony
The Food Stamp Program, administered by the U.S. Department of Agriculture, is proud to be distributing this year the greatest amount of free Meals and Food Stamps ever, to 46 million people.
Meanwhile, the National Park Service, administered by the U.S. Department of the Interior, asks us... "Please Do Not Feed the Animals." Their stated reason for the policy is because "The animals will grow dependent on handouts and will not learn to take care of themselves."
Thus ends today's lesson in irony.
17 April 2011, 11:25
vapodogquote:
if he wanted a .375 Ruger he'd buy a Ruger.
Ain't gonna happen!

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"Socialism is a philosophy of failure, the creed of ignorance, and the gospel of envy, its inherent virtue is the equal sharing of misery."
Winston Churchill
quote:
Originally posted by vapodog:
quote:
if he wanted a .375 Ruger he'd buy a Ruger.
Ain't gonna happen!
And there you have the reason he is building an H&H on a Mauser. Simple, ain't it?
Aut vincere aut mori
18 April 2011, 22:20
Barstoolerquote:
Originally posted by z1r:
quote:
Originally posted by vapodog:
quote:
if he wanted a .375 Ruger he'd buy a Ruger.
Ain't gonna happen!
And there you have the reason he is building an H&H on a Mauser. Simple, ain't it?
I did not say "buy a Ruger" I said why not chamber to a 375 Ruger and save all the grinding required to fit a magnum length cartridge into a standard mauser action. I personally don't care if that is the route you want to go.
Barstooler
quote:
Originally posted by Barstooler:
quote:
Originally posted by z1r:
quote:
Originally posted by vapodog:
quote:
if he wanted a .375 Ruger he'd buy a Ruger.
Ain't gonna happen!
And there you have the reason he is building an H&H on a Mauser. Simple, ain't it?
I did not say "buy a Ruger" I said why not chamber to a 375 Ruger and save all the grinding required to fit a magnum length cartridge into a standard mauser action. I personally don't care if that is the route you want to go.
Barstooler
Again, probably because he wanted an H&H not the Ruger version. But I'll let Vapodog answer.
Aut vincere aut mori
19 April 2011, 03:41
NakihunterI want to build a 404 Jefferey & I have been corresponding with some of you.
Now I have some basics in my head
1. Get action - 1909 Argentine or 1908 Brazilian
2. Get Blackburn or Dwane's bottom metal
3. Grind out the back of the magazine (filler) and the front of the mag recess in the action
The question is - does the action need to heat treated after the grinding?
Thanks for the good thread.
"When the wind stops....start rowing. When the wind starts, get the sail up quick."
I do not have actions heat treated because I am not cutting anywhere that needs heat treatment. I actually mill out the front end, on the feed ramp; even though they may be case hardened, it is not to deep and they mill out fine. That is with 1909s, 1908s, VZ24s, and one byf 41. I can't afford new bottom metal, however and have to alter what I have by welding new fronts and rears in them. Yes, they are actually too narrow for a .404, but they work for 2 down.
19 April 2011, 05:30
Toomany Toolsquote:
The question is - does the action need to heat treated after the grinding?
What are you going to grind? You do not use a grinder to open a Mauser for any cartridge. You use end mills in a vertical milling machine. And then, if you want to you have it re-hardened do it, but it is not necessarily needed.
John Farner
If you haven't, please join the NRA!
19 April 2011, 05:55
vapodogquote:
The question is - does the action need to heat treated after the grinding?
If it's mine.....YES!!!!!
Others may disagree as this subject has left sore egos all over the gunsmithing forum.....
quote:
quote:
Originally posted by Barstooler:
quote:
Originally posted by z1r:
quote:
Originally posted by vapodog:
quote:
if he wanted a .375 Ruger he'd buy a Ruger.
Ain't gonna happen! thumbdown
And there you have the reason he is building an H&H on a Mauser. Simple, ain't it?
I did not say "buy a Ruger" I said why not chamber to a 375 Ruger and save all the grinding required to fit a magnum length cartridge into a standard mauser action. I personally don't care if that is the route you want to go.
Barstooler
Again, probably because he wanted an H&H not the Ruger version. But I'll let Vapodog answer.
Having built a .416 Ruger on a M-98 action two years prior to the .416 Ruger became a SAAMI specked cartridge, I'm quite aware of the .375 Ruger and it's advantages.....
That said, practical is one of many reasons for our decisions.....nostalgia and tradition play a role as well anbd since I do the lion's share of work to my rifles, I'm now looking for a greater challenge than before.....Therefore the H&H version gets the nod over the .375 Ruger!
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"Socialism is a philosophy of failure, the creed of ignorance, and the gospel of envy, its inherent virtue is the equal sharing of misery."
Winston Churchill
20 April 2011, 02:22
AtkinsonHmmm, I have been quoted here and got a call from an AR guy..
It was sorta overstated as to what I have done with the .375. only partially correct, in that I do remove a tad from the rear and some from the front and use a thin piece of steel on a modified magazine. Dennis Olson has been doing this for me for some time now, and I have never had a problem with the 375 or 416 Rem. and I know it has been done by WR and perhaps H&H and even with the 404 and 416 Rigby comm. rifles.
However, IMO the 404 and 416 Rigbys are judicated to Rem. mod. 30, 30-S, and 720s or the big magnum mod. 20 action of yesteryear. Also some of the special made action on the market today, but they are very expensive and not much of an improvement over a well worked Enfield, or particularly a Rem fac. 30-S.
No arguement with who does what on the subject. I suppose there are many ways to skin a cat. I also know that Interarms opens them up fully in front, and some say that weakens the action, but I have never seen a Whitworth blow up because of that. Much to do is made about nothing on the these blogs.
Ray Atkinson
Atkinson Hunting Adventures
10 Ward Lane,
Filer, Idaho, 83328
208-731-4120
rayatkinsonhunting@gmail.com
20 April 2011, 13:45
JBrownquote:
Originally posted by Atkinson:
Hmmm, I have been quoted here and got a call from an AR guy..
It was sorta overstated as to what I have done with the .375. only partially correct, in that I do remove a tad from the rear and some from the front and use a thin piece of steel on a modified magazine. Dennis Olson has been doing this for me for some time now
Ray, I'm sure it was overstated as far as what you have done.
I should have posted the quotes themselves, as I believe they were what started the "open them to the rear only" myth.
Here are the actual quotes I was referring to:
quote:
Originally posted by Atkinson:
It's a simple matter to to open the 24 up to 30-06 or for that matter 375 H&H..and rebarrel one....open them up in the rear.
Mark X 30-06 will it work as a 375?
quote:
Originally posted by Atkinson:
soc,
Yes you can do that but be sure your smith opens the action in the rear, not the front and you will have a nice rifle indeed.
quote:
Originally posted by Atkinson:
Most 404's are converted M-98 std. lenth actions...
They must be openned up completely in the rear and this requires new bottom metal of 375 lenth....
quote:
Originally posted by Atkinson:
GAnyana,<br />I have never seen a Lott that was not on a standard length action, FN, Mauser 98, or Win M-70...<br /><br />Properly openned in the rear with the addition of a Blackburn magazine box, with rails opened they work all great..the Lott is shorter than a 375 H&H, so it works great with any action that will take a 375 H&H...and yes the side of the rear ring should be scolloped and a slot cut in the top of the front ring is acceptable..IF I understand your post properly??
quote:
Originally posted by Atkinson:
Good idea, open it in the rear, change the bolt stop, open the bolt face, do some rail work and chamber and install either a 375 or 416 Rem barrel..All early FN's were opened up to 375's and 404's....
quote:
Originally posted by Atkinson:
It is normally only a matter of rebarreling and it will work most of the time for a 375 and a 416...
The std. FN action action was never intended for a 300 Wby, 7 STW and such ilk, it was not designed for those cartridges and many developed headspace. they don't handle the 300 Wby and hi intensity actions very well, however if they are totally openned up in the rear then one can get by with it but only if properly done and loaded with a degree of intelligence...
I would consider that conversion a move in the right direction and the action will handle the 375 H&H pressures from now on...
Jason
"You're not hard-core, unless you live hard-core."
_______________________
Hunting in Africa is an adventure. The number of variables involved preclude the possibility of a perfect hunt. Some problems will arise. How you decide to handle them will determine how much you enjoy your hunt.
Just tell yourself, "it's all part of the adventure." Remember, if Robert Ruark had gotten upset every time problems with Harry
Selby's flat bed truck delayed the safari, Horn of the Hunter would have read like an indictment of Selby. But Ruark rolled with the punches, poured some gin, and enjoyed the adventure.
-Jason Brown
20 April 2011, 20:07
AtkinsonTaken in full content, my meaning was and always has been to open them in the rear, but you still MUST open them up a tad in the front, but by openning them up in the rear you save a lot of metal in the front where it is supposedly a plus. I simply thought that was understood and I suspect it was by some and not others who take such things to task, and I agree I should have been more precise in my reporting and should have known you can't leave anything unsaid in these forums..
The only guns I know of that are solely opened in front are the Whitworths and I suspect they are of more modern steel and its working.
I apoligize if my intent was not understood or that I thought everyone knew what I was saying.
Ray Atkinson
Atkinson Hunting Adventures
10 Ward Lane,
Filer, Idaho, 83328
208-731-4120
rayatkinsonhunting@gmail.com
20 April 2011, 22:24
Westpacquote:
Originally posted by Atkinson:
The only guns I know of that are solely opened in front are the Whitworths and I suspect they are of more modern steel and its working.
Just to clear this up for you Ray, ALL Mark X Zastava actions, the standard and the Whitworths, are manufactured of modern alloy steels and therefore heat treated like any modern action. And yes, they are opened to the front.
_______________________________________________________________________________
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