bubbamauser Posted February 9, 2006 Report Share Posted February 9, 2006 If anyone has ever done this how do you modify the bolt and extractor, I'm thinking I could get a 28 or 20 ga in and have it clear the lug recesses. I have a receiver laying around I cant use for high pressure but that should be great for this. Link to comment Share on other sites More sharing options...
MorgansBoss Posted February 9, 2006 Report Share Posted February 9, 2006 I haven't actually done it... yet at least, but its one of those projects I do have on the back burner if I ever get to it. I have done some experimentation though and a 20ga. shell does seem to fit nicely. In fact I've even ground a mag. box and follower for the action I intend to use and (sans barrel) it feeds fairly well. My intention is to build a slug gun with a rifled barrel that would be essentially interchangeable with my rifles as the situation dictates. While there's not as wide a selection of 20ga. slugs as there are for 12's, the conversion appears to be much easier for the medium bore. Whitetails don't take a whole lot of killing so I don't anticipate the twenty being a disadvantage at slug ranges providing a suitable projectile can be found. Link to comment Share on other sites More sharing options...
Guest Limpid Lizard Posted February 9, 2006 Report Share Posted February 9, 2006 Conversion to 12 gauge was common in post war Germany. LL Link to comment Share on other sites More sharing options...
z1r Posted February 9, 2006 Report Share Posted February 9, 2006 Conversion to 12 gauge was common in post war Germany. LL Yes, and it required extensive mods too. Including I think a seperate bolt head. Link to comment Share on other sites More sharing options...
MorgansBoss Posted February 9, 2006 Report Share Posted February 9, 2006 It's been a while since I did the work and i don't have access to my notes right now, but I decided it would be too much work for my purposes to do the conversion to 12ga. Although the parts are sometimes available on auction. When I mentioned this project here a month or two ago several other members sent me links to such auctions. The parts didn't go cheap though! Conversely, (again, from memory) conversion to 20ga. seems pretty straight forward with existing parts. Yeah there are a bunch of those Geha and other 12ga. Mausers out there and if available, simply buying one and refurbishing it would be the recommended route if a 12 is desired, but one of these days I'm going to find out just what is involved in the twenty-bore conversion. Link to comment Share on other sites More sharing options...
roscoedoh Posted February 9, 2006 Report Share Posted February 9, 2006 FWIW, You can still find the old Geha 12 gauges pretty inexpensively is you look hard enough. Also, I think the .303 and .410's rim size are close - the Indians made up some .410 Enfields. For what, I haven't figured out yet, but they were called .410 Enfield Muskets. Link to comment Share on other sites More sharing options...
BobDole Posted February 9, 2006 Report Share Posted February 9, 2006 The .410 enfields were for police and prison guards because they were worried about over penetration. Link to comment Share on other sites More sharing options...
donmarkey Posted February 9, 2006 Report Share Posted February 9, 2006 I've got a rusted out Geha in 12ga, missing the bolt, but the other parts are they're. If you need pic or measurements I could get them for you. -Don Link to comment Share on other sites More sharing options...
usmc0332 Posted February 10, 2006 Report Share Posted February 10, 2006 My dad inherited a Geha. It is a cool old gun. The3 bolthead falls off when you remove the bolt. That is how they are. It kicks pretty well, but I have popped a few pigeons with it. It has an awesome tigerstripe stock. I would recommend one of these for us Mauser lovers. Boltheads and extractors are still available. I guess these were the 2 parts that need replacement if any. Link to comment Share on other sites More sharing options...
z1r Posted February 10, 2006 Report Share Posted February 10, 2006 The feed rails obviously need lots of work and most if not all had a piece bolted to the receiver to aid in proper feeding. Certainly worthy of a try but there is lots of work invloved to be sure. Much more required to make a magnum feed. If you have an original please post pics of the various parts, it would aid greatly in not having to reinvent the wheel. Link to comment Share on other sites More sharing options...
Guest Limpid Lizard Posted February 10, 2006 Report Share Posted February 10, 2006 E.R. Shaw has 12 and 20 gauge slug barrel blanks available. I have a Martini action that very likely will end up a 20 gauge slug gun. LL Link to comment Share on other sites More sharing options...
tinkerfive Posted February 10, 2006 Report Share Posted February 10, 2006 I've got a mag(trigger guard) bolt face, extractor, firing pin. If only you could find a bolt body, you could add the parts to Don's and have a complete gun. Tinker Link to comment Share on other sites More sharing options...
dave h Posted February 10, 2006 Report Share Posted February 10, 2006 E.R. Shaw has 12 and 20 gauge slug barrel blanks available. I have a Martini action that very likely will end up a 20 gauge slug gun. LL GREENER converted a number of Martinis over to 12g & they were'nt a bad gun ! A mate in Town owns one & it handles quite nicley ! For a slug Barrel I'd tend to lean towards the 12 g over the 20 for stopping power & range Dave Link to comment Share on other sites More sharing options...
bubbamauser Posted February 10, 2006 Author Report Share Posted February 10, 2006 I was trying to go the route of using existing parts I found a source for 20 Gauge single shot barrels I won't know what kind until it comes in but its cheap enough to work with. I was planning on picking up a box of 20 guage shells and taking the measurements of of them for the bolt face and rails. Does anyone know what will be necessary to make the face work with the rim? I am guessing (and it seems like common sense but I have been wrong as far as common sense goes in the past) in the box the shells are loaded rim in front of the one below. The .410 would be easier and the 12 more effective but I don't plan on using this for deer ( I have a 870 that does the rifled slug job well) for 150 miles around Philly you can only use slugs, no rifles. I had thought of using the .303 case for brass .410 shotshells in a .410 version but its just a little light for me. Link to comment Share on other sites More sharing options...
AzRednek Posted February 10, 2006 Report Share Posted February 10, 2006 The .410 enfields were for police and prison guards because they were worried about over penetration. According to what I recall reading in the book Military Arms of the 20th Century, the Brits armed the Indian and other colonial guards and police with the 410 conversion often with a bayonet with an un-removable sheath in case of a revolt by the native populace. If the armed native guards joined in the revolt they were limited with a short range single shot weapon. Some colonial guards in more hostile areas of the empire were armed with a short harmless stub inside a full length sword sheath or a deliberately imbalanced spear that couldn’t be thrown with any accuracy. Link to comment Share on other sites More sharing options...
Horsefly Posted February 10, 2006 Report Share Posted February 10, 2006 I've read what AZ has,that the British were worried the guns they furnished the natives would be turned on them,and I'm thinking even the .410 they issued India had an odd-ball firing pin to make ammo hard to find.During the Zulu Wars in South Africa,the Zulu's picked up all the guns after battles and used them with terrible results against the British.I'd love to have a '98 20 ga.Jerry Link to comment Share on other sites More sharing options...
Guest Guest Posted February 10, 2006 Report Share Posted February 10, 2006 USMC and Don, could you guys post some pictures of the bolt face , magazine , extracror and ejector. Would give me a good point to start from I'll just do it smaller for the 20. Thanks, Roy Link to comment Share on other sites More sharing options...
Guest Limpid Lizard Posted February 10, 2006 Report Share Posted February 10, 2006 The Greeners were converted to 14 gauge. This was another attempt to limit unauthorized use by the natives. Some may have been converted to 12 by Greener, however I have never seen information that would lead me to believe so. LL Link to comment Share on other sites More sharing options...
AzRednek Posted February 10, 2006 Report Share Posted February 10, 2006 I'd love to have a '98 20 ga.Jerry There is one that has been showing up off and on at an Arizona gunshow table along with a few other Mauser oddities. The seller claims and it appears the shotgun is a factory job. His asking price is over a grand. I believe this is the same seller that has what he claims is a protype 98 chambered in the 7.35 Italian. Link to comment Share on other sites More sharing options...
MorgansBoss Posted February 10, 2006 Report Share Posted February 10, 2006 M98 Bolt diameter is 0.692" 20ga. Shell head diameter is 0.693" 20ga. shell rim diameter is 0.755" Simply turning the bolt face to remove the recess and shortening the firing pin accordingly should provide adequate case-head support and enable use of the standard (though modified) extractor. Of course this will reduce the gun to "push-feed" though. With the magazine properly blocked and the feed rails and follower modified, the 20ga. shell is retained beautifully by the bridge and slight "curl-over" of the receiver's left side. As the shell is moved forward by the bolt the front ring captures the front of the cartridge almost as the rim exists the rear "bridge" - not exactly, but close enough that I think it will be reliable so long as the gun is not completely inverted while working the bolt. The action I "toyed with" holds two shells in the mag + one in the tube. The bolt (without barrel) closes all but about an eighth turn on the shell - the shell rim barley lodging on the inner torque shoulder. Opening this or shortening the bolt a few thou. more should address the issue. My experiment hasn't progressed to the point where I can say these things with absolute authority but I do feel confident it CAN be done simply enough. Link to comment Share on other sites More sharing options...
bubbamauser Posted February 10, 2006 Author Report Share Posted February 10, 2006 MorgansBoss, You answered my next question before I asked it. I set the 20 up against the bolt and saw the overhang, but it is all rim. so far it looks like I will need to open up the inner shoulder of the action for the rim to fit through and it looks like everything else would be repeating what you wrote, as this is too, Thanks kinda puts me at ease with it being doable,I'll probably be posting a lot of stupid questions on this one. Thanks, Roy Link to comment Share on other sites More sharing options...
UniversalFrost Posted February 18, 2006 Report Share Posted February 18, 2006 Why would you want to go and turn a good mauser action into a shotgun? If you want a bolt action shotgun get an old stevens or marlin. I have a stevens in 20 gauge and a Marlin in 12 gauge (they made everything from .410 to 10 gauge). Link to comment Share on other sites More sharing options...
Guest Guest_MorgansBoss_* Posted February 18, 2006 Report Share Posted February 18, 2006 Can't speak for anyone but myself, but to that end my purpose is #1 because I can... just one of those things I'd like to do. #2 I live in an area where some deer hunting is with rifles and some is shotgun only. By making a Mauser slug gun I can build it so as to be completely compatable with the rifle I use. Thus I avoid any confusion or fumbling that could (and does) result from using different guns. That safety is in the same place and works the same. The sights / scope can be the same. The trigger can be made to feel and work the same. Even the shape and (general) weight can be matched. Number two is the practical reason but number one is the fun reason. Most decissions in life are one or the other, when faced with an oportunity to do something fun and practical how can you pass it up? Link to comment Share on other sites More sharing options...
riceone Posted February 18, 2006 Report Share Posted February 18, 2006 never a mauser, but have made 410 shotgun out of T99 Jap and a M95 Steyr. Link to comment Share on other sites More sharing options...
bubbamauser Posted February 18, 2006 Author Report Share Posted February 18, 2006 I want to do just to see if I can, no reason other than that, well maybe just to say that it can be done and I did it. Theres a lot of satisfaction in that Link to comment Share on other sites More sharing options...
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