What would be the feasability of a .30-40 Krag on a Siamese Mauser action?

It was thirtysome years ago I bought my first copy of Bolt Action Rifles by Frank DeHaas. In his evaluation of the Siamese mauser he mentioned the 30/40 Krag as being an ideal choice for the action. About eight years later i was able to pick up a complete siamese rifle for twenty bucks and figured to build a 30/40. It can work but it is NOT an ideal choice. The magazine has to be lengthened and narrowed to get the cartridge to fit and feed. In the end it made a not bad rifle but not so good that it bothered me when I turned it into a 45/70 (this isn't a perfect fit either!)I think it is just as easy to alter a standard mauser 98 to feed the rimmed cartridge and it is likely to be a better quality action. I ended up making my 30/40 hunting rifle on a Lee Enfield which is a little plain but is reliable, rugged and very accurate. My next 303 or 30/40 project will be on a heavily altered P14. Regards, Bill.

Thanks for the feedback. My Siamese is currently wearing a .45-70 barrel-and it doesn't feed well... I thought perhaps the .30-40 might be a better fit. (Besides just wanting a .30-40!)

My Siamese is currently wearing a .45-70 barrel-and it doesn't feed well... I thought perhaps the .30-40 might be a better fit. (Besides just wanting a .30-40

The rails and box need to tailored to the cartridge. You can make it feed most anything if you want to put the work in it. The problem I envision is that is was originally made for a fat rimmed 8mm. To make a 45-70 you need to change the rails and probably the box dimensions. I have not done a Siamese, just P14s in 45-70. On the rails, you need to understand why you are cutting and what will happen when you do. That brings us back to your Siamese. Did anyone alter the rails and box? If not it needs to be done properly for it to feed with 45-70. If you want to go back to the 30-40, you have a problem. The metal is already gone. It is unlikely to work properly as a 30-40. If it does feed in the living room
(with dummies) the sholder in the rails is changed for the 45-70 and the 30-40 will slide foreward under recoil. Even if it has not been touched, the rails may be to wide for the 30-40, since the 8mm Siamese is fat, First guy said it didn't work too well. I would straighten out the 45-70 feeding. One hint is that you need clearance under the extractor so that the rim can slip up in there. Get a P-14 drill rifle to make your 30-40?

[ 05-28-2003, 01:55: Message edited by: scot ]

The Mauser was designed to feed the 8x57 and some others the 7x57.. Although they are basically the same cartridge and action there are suttle difference in the two actions...Changing a Mauser can be done but you would be surprised how few gunsmiths truly understand a Mauser action and what makes it work....

It was never designed to feed rimmed cartridges and it cannot be converted to fee rimmed cartridges 100% of the time...however I have heard some wild claims by suedo smiths and their self claimed abilities.

The Mauser factory made actions specifically for the .303 British and these had a slanted magazine box to put the rim of each cartridge ahead of the one below it in the box. No doubt this action would work fine with .30-40. But they are all on pricey and rare Brit rifles. A similar action but longer box was made for the .400-.350. Also it is possible to alter a Winchester 54 in .30-30 to handle the Krag cartridge, I have seen at least one, stupidly failed to buy it, and there was an article in the American Rifleman about it in the 1940s.

I have encountered at least 5 Winchester Model 54s
rechambered to .30-40 Krag, I also wish I would
have picked one of them up, the prices werent
bad, the last one was less than 300. There was
also an FN Mauser in .30-40 caliber in the GUNLIST
for along time but I think its been sold. I believe it was a single shot though. I myself would rather have the M54 than the hassle of having one built on a Siamese Mauser. It would be
interesting though.

Mr Atkinson;

You need to remember that the early Mausers, M71 and M71/84 where designed for large rimmed bottleneck cartidges. It was not untill the model 1888 that they started to use rimmless cases.

The Mauser plant made M 98 actions for many rimmed bottleneck cartidges. The magazine box was called the slant box, because the rim of the upper case MUST be in front of lower case so they will feed. The shape of the box and rails for the rimmed cartidges are alltogether different than what you would expect.

I have been toying with making rifle for a large rimmed cartidge up on a standard M98 for some time. So I have been studing the Siamese action and guard. Might get some spare time yet to do it.

[ 05-31-2003, 08:29: Message edited by: J Wisner ]