How much effort is involved on making a .375 H&H on an 03A3? Any easier than a 98 mauser? The bolt stop sure seems easier to extend.

And, on a large ring small thread Turk mauser, has anybody built a belted magnum? I was thinking 338 WM. I do not care for any wildcats. My hunting partner has a 35 whelen, so I don't want that otherwise fine caliber, and shaw does not list a 9.3mm barrel on their website.

Thanks

Never done an 03 in 375 but it could certainly be done; done many 98s though. Yes, making a 338 win on a 38 Turk would be easy.

The 338 should be easy enough, my concerns is over the small thread barrel. There is much internet hand-wringing over the idea of a belted magnum, small thread barrel, but I am curious if it actually has been done safely?

Husqvarna did it all the time. 308 and 358 Normas in a small ring Mauser. I have re-barreled a dozen or more.
I once lengthened a Turk to hold an 8MM Rem Mag and it worked out OK. I would not do it again.
Although it is and has been common practice, I don't like to open up a Mauser for the 375 and will no longer do it. I have seen too many which set back from firing. Regards, Bill.

The M70 and M77 Ruger both have a 1" thread shank only a few thousandths larger than the small ring Mauser thread.

quote:

Originally posted by delloro:
The 338 should be easy enough, my concerns is over the small thread barrel. There is much internet hand-wringing over the idea of a belted magnum, small thread barrel, but I am curious if it actually has been done safely?

Thank you all for your replies.

4140 Chrome Moly steel; a .980 thread diameter is plenty. Don't re-chamber a military barrel for a mag, though. As for receiver strength; the A3s are made from 8620, low carbon, chrome moly nickel, usually, and deeply cased; they never set back. Mausers are made from low carbon steel, cased; and sometimes can.

I have done my share of 03 conversions (my favorite rifle) and I will say both the 03 and 03a3 are plenty strong for the .375 H&H. I hate taking off metal in the ramp area, though and always try to talk folks out of 3.6" cartriges (.375 H&H, 458 Lott, 470 Capstick, etc.) and try to steer them to the 3.3" standard length (30-06, the win mags, 416 taylor, etc.)

I would try to steer you towards a .375 Ruger, 9.3x62, .35 Whelen or .416 Taylor. These work fine in an 03a3 with minimal feed rail work and only a bolt face mod if you go to the Taylor.

The round nose .375 fodder in H&H lengths tend to hang up a bit in the feed ramp area unless you take out more metal than "I am comfortable with." (Lest someone accuses me of acting like an expert, I want to qualify that last statement)

I have been using slow powders for a bit on my Taylor and am getting 400gr pills to leave my 24" barrel at a touch shy of 2475fps. That will do anything the 375H&H was intended for (ducking!).

If you will remove the metal from the rear of the receiver and move your mag box wall back, and cut the bolt stop down, the amount of metal that has to be removed from the feed ramp is not much. Everyone wants to remove all of it from the feed ramp, which makes me uncomfortable as well. But since I discovered the 9.3x62 I don't need to build any more 375s for myself. Most of the energy with less than most of the recoil.

I'm interested in your not wanting a 35 Whelen because your hunting partner has one. Strange things can happen when you go hunting and being near someone with the same ammo would be an advantage IMHO.

Don't want to hear my partner accusing me of copying him. That's all. ;-)

Build a 9.3 on the Mauser and a Whelen on the 03 Springfield!.
You can do a 338/06, 35 Whelen, 375/06 or 400 Whelen all very good choices without going to a magnum.

I have had a .375 Taylor (.375/.338) on a 1903 Springfield action for over 50 years now and have never had the slightest problem with it. It can duplicate the full power .375 H&H with no pressure problems or be down loaded as a suitable deer/black bear cartridge. It also does well with cast bullets.

quote:

Originally posted by delloro:
Don't want to hear my partner accusing me of copying him. That's all. ;-)

One up him with a 9,3x62.

The .338-06 is very nice too is you want to be able to use 06 brass.

quote:

Originally posted by delloro:
Don't want to hear my partner accusing me of copying him. That's all. ;-)

You've got to talk about something around the campfire. I look in amazement at the modern world's reliance on stuff that runs on batteries etc and, faced with survival decisions, ask how our ancestors the cavemen and war veterans survived. Eliminating the wrong, unnecessary crap to carry and knowing where to find stuff in emergencies loom large. As with standardised military calibres, having an alternative source for ammo in a hunting camp has to be a plus.

That one of my mates copied my choice of the 338WM is a real boon to me, though we already had two 35 Whelen and two 9.3x62 users in our sambar-hunting group. Those other calibres possibly make more sense these days but my new mate does not reload and he gives me all his cases

quote:

Originally posted by SR4759:
The M70 and M77 Ruger both have a 1" thread shank only a few thousandths larger than the small ring Mauser thread.

quote:

Originally posted by delloro:
The 338 should be easy enough, my concerns is over the small thread barrel. There is much internet hand-wringing over the idea of a belted magnum, small thread barrel, but I am curious if it actually has been done safely?

Major diameter. But with the coarse thread of a Mauser the minor is what concerns me.
Don

If you want a .375 or even .338 mag for use in Africa or Alaska, I would not get one custom-made, even on an action that suited it.

The Zimbabwe PH training courses have found the problems in adapting magazines to other calibres may constitute fatal errors. This is another reason why the 35 Whelen is the most sensible conversion for a Springfield - the case body is exactly the same as the .30/06.

PS: I've altered the text in my post above to make it read better.