Recomendations for BRNO 602 conversion to 404 Jeff

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I was fortunate to acquire a BRNO 602 in 375 H&H(Thanks again to all that held off bidding on the auction rifle) and am now in the process of finding a quality gunsmith that has the time and experience to work on this rifle and convert to 404 Jeffery. I will be doing a full package gunsmith package with new stock and adding safety, trigger, flip up peep sight and other needed upgrades. Whom do you all recommend?

HH
 
I've heard of the name but did not know of anyone having had his work on here. I will put him on the list .
Thanks,

HH
 

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Steve Bertram (http://www.bertramandco.com/) helped me with a Mauser sporter oringinally in .375 H&H, which had been rebarreled to .404 with no other alterations. This ignored the fact that the magazine dimensions for a .404 are different from those for a .375, and as a result, the rifle would not feed correctly. Steve located the correct bottom metal and installed it and also replaced the extractor, which had been opened up too far to accomodate the larger cartridge. It is now all I had hoped for.
.404 Jeffery 002 (2).jpg
 
Dennis Olsen, Plains Montana did a great job on my Winchester 70 375 to 404 conversion, plus stock etc. I am very happy with it. Quite a few here on AH have also used him. It will take a while to finish it. Not sure about a Bruno but he is worth a call.
Olson will tentively be putting a Lilja barrel on my BRNO Mauser 98 this month. Surprisingly, he agreed to thread and ream the barrel but absolutely refuses to do the feeding changes. I bought a 416 Rem bottom metal from Swift and it appears to work with no modification. A little narrow at shoulder but shouldn't be a problem. I widened the 8mm receiver to match the bottom metal width and modified the loading ramp (quite a bit). The left feeding rail should require no modification and only slight more work to right one once the new barrel is installed. I bought a magnum follower from New England Custom Gun and it only required very minor modification (smoothing a couple of corners). Probably could have got by with standard length follower. I just finished installing a 3-position Model 70 style safety from Parkwest. It didn't like my Timney trigger. Also a bit of poor machining on the safety took a while to diagnose and fix. The cocking piece on this gun was buggered by previous owner which was also causing problems with new safety. Replacement cocking piece will be delivered tomorrow. This week a local machinist will open the bolt. Overall, I am pleased with progress so far. Things I expected to be problematic weren't but there were other surprises. No gunsmiths left in town (or within a day's drive) so I'm doing most of the work. It's not rocket science ... but pretty close to it.
 
Dennis Olson did my Win Mod 70 conversion from 300 RUM to 404J. I got a Krieger barrel made and shipped directly to Dennis. He did a great job and very reasonably priced.
 
Interesting that Dennis will not do the feeding changes on a BRNO, I wonder what the difference is between it and a Win Mod 70?
It may be for just my situation. Possibly he's too busy right now? Modifying standard Mauser bottom metal to feed 404 is a bit taller order. It is doable but a lot more work. Perhaps he didn't understand I was changing bottom metal. Perhaps at that point I didn't know I'd be changing bottom metal. Adjusting the feeding is definitely the tricky part. I recall one fella on another forum saying it took him sixteen hours of careful carving to finally get the ramp and rails feeding correctly.
 
Wayne Jakobson at AHR used to do these conversions. However, he stopped doing so several years ago. Now work on CZ 550(s) and the BRNO ZKK 602(s) is being handled by https://www.matrixgunsmithing.com/

Wayne taught the gunsmiths at Matrix how to do this . You might try giving them a call.
 
I would contact Wayne at AHR. He is still doing custom builds on either his actions or yours. Talked to him last week about using one of my CZs to do a 404 build.
 
It may be for just my situation. Possibly he's too busy right now? Modifying standard Mauser bottom metal to feed 404 is a bit taller order. It is doable but a lot more work. Perhaps he didn't understand I was changing bottom metal. Perhaps at that point I didn't know I'd be changing bottom metal. Adjusting the feeding is definitely the tricky part. I recall one fella on another forum saying it took him sixteen hours of careful carving to finally get the ramp and rails feeding correctly.
Adjusting feeding is difficult- i did my own. 3 variables- magazine width, feed ramp angle and magazine lips. And all vary differently along the feed cycle. And your follower needs the right profile to start the process. And then changing feed ramp impacts where the case touches the feed lips so many hours of fun. Probably not profitable or at least too expensive for the customer so best avoided.
 
Adjusting feeding is difficult- i did my own. 3 variables- magazine width, feed ramp angle and magazine lips. And all vary differently along the feed cycle. And your follower needs the right profile to start the process. And then changing feed ramp impacts where the case touches the feed lips so many hours of fun. Probably not profitable or at least too expensive for the customer so best avoided.
I did my own as well. Turned out it wasn't as difficult as anticipated. I bought 416 Rem Mag bottom metal from Swift and then started by making the bottom of receiver match up to it. I used a Dremel tool with grinding wheel for most of that work. I also picked up a magnum follower from New England Custom Gun (though the standard follower works okay I'm told). Opened up the end of the receiver till the longer follower came up freely. Then I started working on angling the feeding ramp, removing a little metal and trying a dud shell until I had it right and tip of bullet moved up without bumping into the receiver. Surprised that the left feeding rail required no modification. Very little was needed to reshape the shoulder area of right rail to get top two STACKED loads to cycle. The problem was third shell was hanging up under the right rail. Rather than alter the rail and risk taking too much I decided to change the follower. If I took too much metal from the receiver, I could always fall back on the standard length one or order another magnum follower. Take too much metal from rail and receiver is no good. End of project. So I carved away some of the upright feeding ridge in the follower. Started about quarter inch ahead of the back end of follower and took out enough metal to allow the shell to jump sideways at the point where it was binding on receiver rail. Left the quarter inch untouched at back to ensure the last cartridge didn't roll out prematurely when loading. It works perfectly! Last issue I finally resolved last night was snap over wasn't consistent loading shells dropped in the magazine. Kinda important to fix that as this dangerous game rifle only holds three in the box. I relieved some spring tension on the extractor and that did the trick. Removed the extractor and reshaped it by bending the bow slightly. That did it. Also seems to make the action cycle smoother for some reason. Probably allowing shells to pop up into bolt face easier. It is now very slick! I never did a thing to the 416 bottom metal. Worked fine as is. I actually anticipated opening it up a bit to satisfy Paul Mauser's cosine 30 degree formula for stacking in the box but it wasn't necessary.
 
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I have seen a few approaches and i am not sure which is best. My brothers 416 slide the cartridge forward a bit and then it pops up under the claw and feeds straight into the chamber. I set mine so that it slides into the chamber in the centre and then comes off the rails under the claw. I thoight a lot about it. I think you get the magazine correct with follower and then set the incoming bullet nose height with the ramp and lastly fix the rails. Like a good golf swing, lots of things happening to make it work.
 
I did my own as well. Turned out it wasn't as difficult as anticipated. I bought 416 Rem Mag bottom metal from Swift and then started by making the bottom of receiver match up to it. I used a Dremel tool with grinding wheel for most of that work. I also picked up a magnum follower from New England Custom Gun (though the standard follower works okay I'm told). Opened up the end of the receiver till the longer follower came up freely. Then I started working on angling the feeding ramp, removing a little metal and trying a dud shell until I had it right and tip of bullet moved up without bumping into the receiver. Surprised that the left feeding rail required no modification. Very little was needed to reshape the shoulder area of right rail to get top two STACKED loads to cycle. The problem was third shell was hanging up under the right rail. Rather than alter the rail and risk taking too much I decided to change the follower. If I took too much metal from the receiver, I could always fall back on the standard length one or order another magnum follower. Take too much metal from rail and receiver is no good. End of project. So I carved away some of the upright feeding ridge in the follower. Started about quarter inch ahead of the back end of follower and took out enough metal to allow the shell to jump sideways at the point where it was binding on receiver rail. Left the quarter inch untouched at back to ensure the last cartridge didn't roll out prematurely when loading. It works perfectly! Last issue I finally resolved last night was snap over wasn't consistent loading shells dropped in the magazine. Kinda important to fix that as this dangerous game rifle only holds three in the box. I relieved some spring tension on the extractor and that did the trick. Removed the extractor and reshaped it by bending the bow slightly. That did it. Also seems to make the action cycle smoother for some reason. Probably allowing shells to pop up into bolt face easier. It is now very slick! I never did a thing to the 416 bottom metal. Worked fine as is. I actually anticipated opening it up a bit to satisfy Paul Mauser's cosine 30 degree formula for stacking in the box but it wasn't necessary.
Didn't have my coffee when I wrote this. Carving on the follower instead of receiver to make the last shell in magazine feed is less risky than carving on receiver. If the stacked shells feed through the rails, then don't mess with changing the receiver. Last shell not feeding was the problem and it was clearly a problem caused by the follower underneath it. Follower can be replaced if too much is carved away. Carve off too much on the feeding rails and shells won't stay stacked in the magazine. Then the action is toast. My follower isn't very pretty now but I don't care. The gun works.
 

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