Feed lips/Rails.... when too much is taken off....?

[Frederik]

@DWB Now your video shows in the responce

 

[DWB]

I still have to go and test it, but my head is telling me this did not happen during our last shoot as the bolt still had the case in the extractor, not allowing it to twist that far right...

Will try it a bit later.

But the main question is:
Can they be welded up? And if so, Which Method? (Sounds like Laser?)

Other than this the gun feeds surprisingly well....

 

[DWB]

Well Thankfully it seems to be working just fine when there's a dummy round or case being extracted!!!!

 

[Ontario Hunter]

Typical Mauser type action with enough wiggle to prevent it from getting stuck...

The problem is it is at that point in the movement where the bolt is forced far enough to the left at the back (The front is then obviously the furthest to the right) with the upward camming action still being forced on the bolt handle....

I cycle as fast as I can and am a big guy, so it is probably a perfect storm situation that won't happen to anyone else... And will probably not happen when cycled out of the shoulder.

Just to give you a bit of an idea....:
This is how it must perform

Interesting. Again, is the sear for trigger engagement that hangs below the cocking piece getting caught as it enters the channel in the tang? From what you are describing, I think that may be the problem. If the catch is not serious, it may be fixable by beveling the EDGE OF LEFT FRONT FACE of the sear. As long as the face proper is not touched (only the edge), the trigger pull weight should not change significantly (if at all). Mauser cocking pieces are fairly easy to come by (but are not all exactly the same). Might want to try shopping for a replacement to try bevel adjustment and keep the one you have for backup. By beveling that front face, the sear should find the tang channel easier. Sounds like that left edge of sear. is binding as it enters the channel.

 

[DWB]

Thank you, but the the bolt is way past the cocking part by the time it gets stuck.

 

[gbflyer]

Dan Armstrong in Fairbanks Alaska could weld that for you. Not sure if he would though. He’s picky about projects. Send him an email and ask. His bedside is rough but he’s as honorable as they come.

 

[DWB]

Thanks, I am.just in South Africa which is a tad far

 

[Hunter4752001]

The problem originates with using a less than highest quality gunsmith. Asking a group of people with unknown skills really isn't the way to go. Lots of people on this forum have experience but that counts for little when they can't put their hands on the rifle and examine it. Likewise recommending specialist gunsmiths in the US is useless when shipping the rifle isn't viable.

Find the best gunsmith in SA and see what they say - everything else is just delay. Between, yourself, Frederik and the various BASA members, I'm sure someone knows of of a South African gunsmith with the right skills, (including the knowledge to say it can't be fixed- should that be the case).

 

[DWB]

I fully hear and agree with your comments @Hunter4752001

However, the guy who made the initial buggerup is supposedly one of the best big bore gunsmiths in SA.

I stay far from everywhere, so I try to do my homework and then go look for someone who can offer the solution.

 

[Dewald]

Deon, find a .375 ZKK602 that some fool circumcised for a silencer, with one of those horrible Monte Carlo stocks, pay R20k, get a new action, sell the stock for R2-3k and be done with it…

 

[Ontario Hunter]

I too am remotely located ... well, re gunsmithing services anyway. I had to have my 404 barrel made in Montana because no one up here could make me one. Thanks to new US export regs, sending the barrel here was problematic. So I dropped the 30-06 barreled Czech Mauser into a stock and drove it to Montana (I'm still a US citizen and also Canadian Permanent Resident licensed to possess firearms so I can move freely across the border with a WHOLE gun). It is a thirty hour drive. Then a gunsmith there (Dennis Olsen who is well known on AH) installed the barrel. But he would not touch the feeding adjustments. Duane Wiebe, a great custom gun builder in Washinton, was very encouraging and his $25 booklet intended for gunsmiths and machinists was very helpful. On his advice I ordered new bottom metal for 416 Rem Mag from Swift-Blackburn which worked out very well. I had to carve out just enough of the bottom of receiver to make it meet up with the new bottom metal. Otherwise the follower could get hung up causing the last shell to jam. This would appear to be where your guy went wrong. After the bottom metal matched the receiver, the rifle would load shells fine without modifying the magazine box, but only off the left rail. I had to tune the right feeding rail (and of course significantly modify the feeding ramp). The bolt face was opened up by a local machinist using Weibe's booklet. Surprisingly, modifying the extractor to snap over on cartridge dropped in the chamber was perhaps the biggest challenge. Very tricky, but I seem to have finally mastered it. I would say the only possible shortcoming is the gun does not eject shells as vigorously as formerly did. Empties still seem to eject okay but not broadcast as far. Loaded cartridges almost drop at my feet when ejected. Is that a shortcoming or a benefit? Perhaps more the latter considering the scarcity of components these days. I'm sure I could "fix" the issue by modifying the ejector but I'll leave it alone for now.

The moral of this story is you should not shy away from trying to figure out a solution on your own. You say the bolt "overcams" causing the lug to jump the rail. I can't see how that is possible for a Mauser bolt. The guide ridge machined into the bolt (it tucks in between extractor and bolt when bolt is closed) keeps it in line during closing as long as the ridge is traveling through the rear ring. My rifle is not at hand so I'm working from memory. As I recall, the guide ridge on the bolt does not leave the channel in the rear ring until the end of closing when the lugs should be clear of the rails and in their socket in forward ring. So I don't think overcamming is the issue but rather sloppy sideways movement of the bolt during closing.

The only way your first gunsmith could add an extra round to magazine is to expand its capacity. How did he attempt this? Did he widen the box or lengthen it or both?

One quick and harmless potential solution to try: remove the follower from floorplate and expand the spring by pulling it apart, then reinstall. This will increase the pressure of shells in the magazine on the bolt during its cycling travels. May be sufficient added pressure to hold the bolt lugs in place against the top feeding rails during cycling. Depending on what if anything has been done to modify those top feeding fingers (seems no modification since you say there are no feeding issues), shells in the magazine may jump out of the box prematurely, but I doubt that will happen since it seems the gunsmith's fiddling was with forward portion of rails. Most of the receiver's critical gripping of cartridges in the magazine is at the back end of the box. If the spring pressure is too much and shells jump prematurely, just bend the spring back to where it was. If this cures the problem of bolt lugs being out of alignment during cycling, you could probably expect the gun may still jamb when closing on an empty magazine or when dropping a round in the chamber to snap over for fast follow up shot with an empty magazine (maybe this model does not allow snap over anyway). But you'll still have a gun that almost works most of the time. Try it. You have nothing to lose. However, staggered cartridges in the box pushing up on the bolt from below are not centered underneath so increased follower spring pressure may not have any effect because pressure is placed only on one side of the round bolt. The lug on opposite side might still be able to jump the rail. Indeed, it may be forced to jump the rail.

 

[Tokoloshe Safaris]

Did that guy push open the sides of magazine box too? My guess is yes.

Hi, I am not disputing what you say, but could any gunsmith be that stupid?

 

[Ontario Hunter]

Hi, I am not disputing what you say, but could any gunsmith be that stupid?

Look at the photo. The sides of my original Mauser 98 magazine box are straight back to front, and the matching contour on the receiver is also straight. My new bottom metal from Swift has straight sided box end to end. The outside edges of this receiver do not appear straight. The sides appear to be bulged. The gunsmith was supposed to increase magazine capacity one more cartridge, not change to a larger caliber (my challenge converting 8mm Mauser to 404 Jeffery). How did he do that? Sensible way would be to lengthen the box. There would be no reason for him to touch the rails or receiver if he simply made the box deeper. But making the box longer requires changing the depth of bottom metal = changing the stock = custom made stock and bottom metal = $$$!. Perhaps he thought he could avoid that by widening the box instead. Maybe that would work, maybe not. Remember that Jeffery built their original 404 on standard Mausers by cutting away the sides of the magazine box and opening up the stock to handle much thicker and longer cartridges. Of course, they also had to significantly modify the feeding ramp and rails to match the new dimensions of the magazine. I think that may be where this guy screwed up. Obviously, if he widened the box (and I'm betting that's the option he chose over lengthening it), then the follower for sure is not going to make it past edge of the receiver where it meets the magazine. Depending on how much he widened the box, perhaps even round cartridges would not roll past that edge. The first cartridge might cycle into the chamber but following cartridges would hang up in the box. Not good for a dangerous game rifle! At that point he should have abandoned the scheme. Instead, he opted to follow Jeffery's lead and attempted to make the receiver bottom match the new much wider dimensions of the box. My choice would have been to simply bevel the edges of the receiver bottom and bevel the keepers on left side of follower (follower is tipped to that side against magazine/receiver wall when shell is loaded on it). See if that works (and it might work depending on how much wider he made the box). If the shells in the box still wouldn't slip over the edge where receiver meets the box, then throw in the towel with this idea. Tell the client there's only one way to add an extra round capacity, and that's to extend the bottom metal (= custom made bottom metal = $$$) and make a new stock ( = more $$$). Instead of quitting he went ahead and carved into the bottom bolt rails too far in an attempt to make the receiver match a magazine that was expanded way too wide.

So how stupid was this gunsmith? Presuming he did try to widen the box rather than make it deeper, not smart enough to give up on the idea before wrecking the gun.

 

[IvW]

TIG or Oxygen and Acetelyne with a 5% nickel rod. You can protect the ends of the action from getting hot. You wil need a specialist welder.
I had rails welded on one of my ZKK 602 actions many moons ago which was also butchered by a smith. The guy who fixed it is no longer with us.

What caliber is it?

 

[IvW]

I have 3 x ZKK602 actions we can use for comparison and measurements.
Relatively easy fix but it will be a slow process as after welding it will have to be re shaped

 

[DWB]

TIG or Oxygen and Acetelyne with a 5% nickel rod. You can protect the ends of the action from getting hot. You wil need a specialist welder.
I had rails welded on one of my ZKK 602 actions many moons ago which was also butchered by a smith. The guy who fixed it is no longer with us.

What caliber is it?

450 Rigby.

Dropping it with a reliable smith this afternoon.

 

[DWB]

I have 3 x ZKK602 actions we can use for comparison and measurements.
Relatively easy fix but it will be a slow process as after welding it will have to be re shaped

Thank you!

Will definitely speak to you if getting stuck.

I think even rebuilding 5mm of that feed lip will solve the problem