OntarioHunter
Well-known member
- Joined
- Sep 11, 2020
- Messages
- 5,980
I started this project back in April. I'm building a 404 Jeffery on a standard Mauser 98 action (BRNO vz.24). Mostly did it for the challenge ... and the history. Jeffery designed this cartridge in 1905 to be the first elephant gun rimless cartridge specifically for the relatively new Mauser repeating rifles. Up to this time essentially all the dangerous game cartidges/guns were double rifles. Besides the disadvantage of only having two rounds loaded, double rifles were exceedingly difficult to manufacture and therefore exceedingly expensive. Jeffery designed a big bore to fit in existing Mauser 98 design actions. He did this by cutting away the sides of the 8mm magazine box, opening the wood to hold three wider 404 cartridges, moving the feeding ramp forward into the front ring, opening the bolt face (to accept wider 404 rim), and modifying the feeding rails. It worked. Jeffery was able to produce big bore rifles relatively cheaply that were plenty powerful enough to kill dangerous game effectively. Initially Jeffery offered ammo in both 300 gr and 400 gr, the latter screaming along at 2130 fps. An added bonus was (and still is) relatively mild felt recoil (relative to typical 500 to 700 Nitro Express double rifle elephant guns). Jeffery's main competitor Rigby was keen to capitalize but was wary of building anything bigger on a standard length action. So he requested that Mauser build him something larger and stronger for his new 416 cartridge (which he originally did fit into a standard Mauser 98). And thus the magnum action was born in 1913.
I chose a different path than Jeffery. I ordered bottom metal (trigger guard, floor plate, magazine box) for 416 Remington magnum from Blackburn-Swift (of Swift Ammunition). I planned to widen the box slightly to meet Paul Mauser's cosine of 30 degrees formula but it appears I can get by with it as is. I used a Dremel tool to grind open the belly of receiver to match the shape of Swift box. Then the feeding ramp needed to be moved forward into the front ring, again using a Dremel grinder. A Timney trigger was installed easily but getting it to match up to Model 70 style 3-position safety and shroud from Parkwest proved to be a challenge. I think most of the problem was due to modifications to cocking piece done by previous owner, presumably to make the trigger with safety he installed work (the military safety and trigger was back in the action when I bought it but cut out on bolt shroud ring indicates a side mount trigger block safety must have been in the gun at some point). On close examination I discovered a crack in military bolt shroud so I decided to go with expensive new 3-position safety. Turns out previous owner slightly warped the back end of the bolt when he welded on a new scope relief bolt handle. I fought the installation of new shroud and safety for several days before discovering the source of the problem. I was finally able to cure it by very slightly reshaping/polishing the striker which was binding in the new shroud. I bought an old new stock that had never been installed. It has a side safety cutout that I'll have to fill. Got a good deal on the stock, it's a good stout design/wood, and the old fella could use the money (we made the deal in parking lot of hospital where he was getting treatment). A good piece of wood to use as a learning tool. I'm right now waiting for Lidja of Plains, MT to finish the barrel. Owens, also of Plains, will thread, ream, head space, and crown it. I will finish bedding the action and tuning the feeding rails (Owens resolutely refuses to do that). I will also attach the Winchester Model 70 Express iron sights exactly the same as on my Springfield. The rail is also nearly a duplicate of the one on the Springfield. This gun will wear the Sprinfield's 1970s retired 3x Weaver scope, also with Warne QD rings. Then the 404 should be ready for Africa. I may have time to get it blued before leaving in August but I doubt it. If not, everything will be in the white except receiver, scope, rings, and iron sights. Yesterday I added the zebrawood fore end cap. Made it from a blank. Today I plan to make a grip cap to match. The lightning bolt pattern in the grip cap has given me the idea of naming this gun Thor's Hammer. Naah! New England Custom Gun furnished the magnum length follower, although standard length one that was in it worked fine. I also ordered a Cape buffalo ammo wallet to hold five rounds on my belt. Very nice quality and a good price. No flap on this one as I don't want to deal with that if I have to load quickly before getting stomped to death. I will probably also start applying Linspeed oil finish to the stock today. It should require at least a dozen coats.
I chose a different path than Jeffery. I ordered bottom metal (trigger guard, floor plate, magazine box) for 416 Remington magnum from Blackburn-Swift (of Swift Ammunition). I planned to widen the box slightly to meet Paul Mauser's cosine of 30 degrees formula but it appears I can get by with it as is. I used a Dremel tool to grind open the belly of receiver to match the shape of Swift box. Then the feeding ramp needed to be moved forward into the front ring, again using a Dremel grinder. A Timney trigger was installed easily but getting it to match up to Model 70 style 3-position safety and shroud from Parkwest proved to be a challenge. I think most of the problem was due to modifications to cocking piece done by previous owner, presumably to make the trigger with safety he installed work (the military safety and trigger was back in the action when I bought it but cut out on bolt shroud ring indicates a side mount trigger block safety must have been in the gun at some point). On close examination I discovered a crack in military bolt shroud so I decided to go with expensive new 3-position safety. Turns out previous owner slightly warped the back end of the bolt when he welded on a new scope relief bolt handle. I fought the installation of new shroud and safety for several days before discovering the source of the problem. I was finally able to cure it by very slightly reshaping/polishing the striker which was binding in the new shroud. I bought an old new stock that had never been installed. It has a side safety cutout that I'll have to fill. Got a good deal on the stock, it's a good stout design/wood, and the old fella could use the money (we made the deal in parking lot of hospital where he was getting treatment). A good piece of wood to use as a learning tool. I'm right now waiting for Lidja of Plains, MT to finish the barrel. Owens, also of Plains, will thread, ream, head space, and crown it. I will finish bedding the action and tuning the feeding rails (Owens resolutely refuses to do that). I will also attach the Winchester Model 70 Express iron sights exactly the same as on my Springfield. The rail is also nearly a duplicate of the one on the Springfield. This gun will wear the Sprinfield's 1970s retired 3x Weaver scope, also with Warne QD rings. Then the 404 should be ready for Africa. I may have time to get it blued before leaving in August but I doubt it. If not, everything will be in the white except receiver, scope, rings, and iron sights. Yesterday I added the zebrawood fore end cap. Made it from a blank. Today I plan to make a grip cap to match. The lightning bolt pattern in the grip cap has given me the idea of naming this gun Thor's Hammer. Naah! New England Custom Gun furnished the magnum length follower, although standard length one that was in it worked fine. I also ordered a Cape buffalo ammo wallet to hold five rounds on my belt. Very nice quality and a good price. No flap on this one as I don't want to deal with that if I have to load quickly before getting stomped to death. I will probably also start applying Linspeed oil finish to the stock today. It should require at least a dozen coats.
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