A little fix for a big problem

[Ontario Hunter]

Heading to the range today to check my rifles for upcoming safari. As always, I cycle newly loaded ammo after closing up the bench. To my surprise I found the last round in my 404J 98 Mauser's magazine was jamming but only when box was filled. Single in the box loaded properly. Bullets on last cartridges were nose diving into ramp. I rechecked several times with different cartridges and same thing. This was curious because I have four dummy rounds I have cycled hundreds of times with box fully loaded and no problem. The dummy rounds are RWS brass and the sticky ones are Hornady. I'm not loading the RWS brass because cases are too short and rim thickness inconsistent. So this must be a problem with magazine spring or follower. Tried adding some tension to the spring and that didn't help. After careful examination, I found the cartridge was hanging up below the feeding rail (a huge relief that it wasn't a problem with rails!). The follower was getting caught sometimes where the bottom of receiver meets the magazine box. This is my build on a standard action Czech vs.24 8mm action. The obvious fix would appear to be remove the action and clean up or modify the bottom throat of receiver. Hmmm. Looking at the removed aftermarket NECG magnum follower I noticed the bolt side edge was rather abrupt and sharp. I used emery cloth to smooth it and very slightly bevel the top edge. And that's all it needed. I cycled the entire box twice and no issues. At some point I'll pull the action to do maintenance and I'll maybe smooth the edge of receiver throat a bit.

The gouge in the guide is a modification during final tuning for proper cycling. Modify left feeding rail with fully loaded magazine, then right (bolt side) rail for two in the box, and then modify follower to cycle with just one in the box. The bevel on edge of follower is barely noticable ... but it was enough.

 

[Ontario Hunter]

When check cycling new loads for my Springfield 03A3 30-06 I noticed it was picking up cartridges from the magazine a bit rough. I removed the bolt and pushed a cartridge onto the bolt face. Yep, the rim was catching on the claw as I pushed it up. Catching more than it should anyway per Duane Wiebe's booklet. So I used a cylinder carbide tip in Dremel tool to remove just a bit of lower corner of the claw. Wow, what a difference! The bolt picks up cartridges from magazine smooth as glass.

 

[MTJumbo]

It is good that you found the problem before you needed that last cartridge for the charging buffalo. I had a similar problem with a .375 H&H built on an early Montana Rifle action. If the follower spring is not lined up properly or the follower edge becomes caught under a rail the last cartridge fails to feed. IMO, maybe you should take a small file with you in your gun care bag. Just saying, it might be worth a man's life. I'm glad you found and corrected the problem. Good luck wiith your hunt.

 

[AZDAVE]

Good catch. have a good hunt

 

[Nhoro]

I had a similar problem with a CZ 550 in 458 lott. The cartridge rides up that corner and up the claw. It is good to round or even angle that corner and then polish the edge of the claw.mine fed fine but was hard and gritty. I also polished the flat face of the bolt. The back of the brass case slides up the face as well.