I’ve got a CZ550 Safari Magnum in .375H&H that has a persistent problem that I can’t fix. I’m hoping the AR brain trust will have an idea.

The last round in the magazine often jams when pushing the bolt forward to chamber the round. It seems to happen more often the faster and harder you work the bolt. It jams so hard sometimes you need a screwdriver and hammer to get it out. Basically, it seems to come up out of the magazine at too sharp an angle too soon, and the back end of the cartridge sticks under the right side feed rail at a little in front of the middle. This only happens with the last round. It does not happen with any other round. It does not happen if you work the bolt slowly or gently.

I have had the feed rails polished—twice. The gun shop hasn’t been able to replicate the problem. But they only run a few rounds through it before calling it good and didn’t work the bolt very aggressively. I’ve also installed a new +10% follower spring from Brownells. Neither helped at all.

I don’t want to get rid of the gun for sentimental reasons. But this problem is quite irritating. Has anyone else experienced this or got a fix for it?

Thank you.

LWD

I have my bolt rifles slicked up by Griffin & Howe...not cheap (about $400), but worth it IMHO. I'm sure there's a number of experienced gunsmiths on this forum who could do the same. BTW, it always seems to be the last shell that's a problem.

Are you talking factory rounds or reloads? Which bullet? Is COL within spec? Have you tried different COL?

Try a different follower. If that doesn't fix it send it back to CZ, the cutouts on the rail may be too far back.

I owned a CZ 375 h&h that would also jam up. I ended up reshaping the feed rail and claw extractor little by little until it fed fine.
It was a real PITA. I would send it back to CZ. It's fairly common to get a CZ big bore that doesn't feed well.
Or take it back to the gunsmith that you paid to fix the problem and show them your self how it jams up.
The other option is to send it to AHR for $500 they do really good work.

Look at the follower. I had a thread on this some years back. My hunting partner is a Guild smith and he reworked my follower which completely eliminated the last round feed issue. I had the metal follower which would cock and bind when the round was running hard over the sharp lip. This would bind the last round badly. When all was said and done, he reshaped the follower along the lines of the M70 design while giving it some relief to prevent any binding. As a result, it now feeds slick regardless the bolt speed.

I was lucky in that he had a computer operated indoor range facility where I could run the rifle so he could observe the malfunction to diagnose the problem. It didn't take him 15 minutes to figure it out and we were able to test his fix right on the spot.

Good Luck

Thank you all for the quick responses.

To answer a question, this has happened with factory loads and hand loads of both Barnes TSX and 300 grain roundnose. I even loaded some dummy rounds to test with to insure that I really did have a problem before working on it some more.

Where would you get a new follower? I've searched Brownells and Midway and didn't find anything that seemed to be the replacement part. I'm reluctant to call CZ USA for one since it seems to be their following that is the problem.

Thanks again.

LWD

quote:

Originally posted by LWD:
Thank you all for the quick responses.

To answer a question, this has happened with factory loads and hand loads of both Barnes TSX and 300 grain roundnose. I even loaded some dummy rounds to test with to insure that I really did have a problem before working on it some more.

Where would you get a new follower? I've searched Brownells and Midway and didn't find anything that seemed to be the replacement part. I'm reluctant to call CZ USA for one since it seems to be their following that is the problem.

Thanks again.

LWD

Actually, it would help for you to call CZ. They've undoubtedly heard rumors of the problem and may have a fix. PLUS, it is calls from loyal customers who bring about design changes in future models. They are a business and won't want to let this be the final word in the big bore community. They are making a big push to reach that community with useable, huntable firearms. At least we got Barnes to momentarily hold on to their great flat-nose solids before throwing them all out for a 'smooth-feeding' roundnose. Moral of the story is get the flatnose solids to feed!

When I obtained my opened up Oberndorf Mauser from Rhodesia as it was called way back then, it feed shockingly from the mag, scratched the hell out of the cases and was just a dog. I don't think it had been used in its .404 guise. Anyway having done a lot of 'remedial' gunsmithing I carefully observed the cartridge feed from the mag before attempting any work on the rails or feed ramp. A few seconds of work to stone off the sharp heel on the claw extractor (cut back and round off the heel), and I had the beast feeding like a hot knife through butter. Not a mark on a case and oh so slick and never a fail to feed every round from that mag.
Would have been easy to start opening up the guide rails or stuffing up the feed ramp but these were not the problem and I suspect the factory full extractor heel shape causes more feed problems in Mausers than anything else.

quote:

Originally posted by LWD:
Thank you all for the quick responses.

To answer a question, this has happened with factory loads and hand loads of both Barnes TSX and 300 grain roundnose. I even loaded some dummy rounds to test with to insure that I really did have a problem before working on it some more.

Where would you get a new follower? I've searched Brownells and Midway and didn't find anything that seemed to be the replacement part. I'm reluctant to call CZ USA for one since it seems to be their following that is the problem.

Thanks again.

LWD

A new follower might be one they use for the Rigby or the Lott or whatever follower they have that is different than for your 375.

Probably won't work but it might be a quick fix.

It's fixable, just gotta figure out how!

It's really a 10 minute job with a flexible shaft grinder and small stone. You grind away the left side of the rib down the center of the follower. You start about 1/3 from the rear and grind pretty heavily tapering to the front. What you are doing is letting the last round move to the left sooner that it normally does allowing it to come up under the extractor. I learned the trick from David Miller and it works EVERY time. I posted the tip way back.

Again, thank you all for the insights and suggestions.

quote:

It's really a 10 minute job with a flexible shaft grinder and small stone. You grind away the left side of the rib down the center of the follower. You start about 1/3 from the rear and grind pretty heavily tapering to the front. What you are doing is letting the last round move to the left sooner that it normally does allowing it to come up under the extractor. I learned the trick from David Miller and it works EVERY time. I posted the tip way back.

On this, is this closer to bubba-smithing or gun-smithing? My skills are not much beyond the bubba-smithing level. It sounds pretty straightforward but......

LWD

It just depends on how well you work with hand tools. You know if you own a flexible shaft grinder you are most probably able to use it. It's not a particularly difficult procedure but does require a staedy hand and some skill with the grinder. I will have to admit I attended gunsmith school and have been tinkering for over 50 years. I don't know the cost of a new follower from CZ but can't be terribly expensive. That is if you really mess it up.

change the spring

quote:

Originally posted by zimbabwe:
It's really a 10 minute job with a flexible shaft grinder and small stone. You grind away the left side of the rib down the center of the follower. You start about 1/3 from the rear and grind pretty heavily tapering to the front. What you are doing is letting the last round move to the left sooner that it normally does allowing it to come up under the extractor. I learned the trick from David Miller and it works EVERY time. I posted the tip way back.

Here's a picture of a FN follower modified as described above.

The JC Higgins started life as a .270 Win and became a .375 Ruger with a McGowan barrel. Among the modifications made so the action would function properly with the larger case where those made to the follower. As it stands, this rifle functions perfectly. Bill Leeper of Elko, B.C. was the gunsmith.

As an experiment, I substituted an unmodufied follower to see if I could see/feel a difference in feeding. While the round fed ok, there was a definate resistance when pushing the round foreward that isn't there with the modified follower.

Don't worry about confidence in your rifle, just keep sending it back. Or you could actually
buy something that works all the time. If your going on one safari, buy the best rifle you can, or if your going back time and again
buy the best damn rifle on the planet. Short of your income. Memories and firearms last forever.
Think and choose right.
Good Luck

This is my CZ 550 416Rigby with the follower modified

Well, it seems that a little grinding has fixed the problem. I had to grind it down further forward than I guessed. But I keep taking more off further down the follower. This morning I could get no jams of the last round. It seems the problem has been solved with some assistance from the AR brain trust.

Thank you all for the insights and suggestions.

Best regards,

LWD

Excellent. You should give special thanks to 'Zimbabwe'.

Excellent thread.

Love to learn about these tweaks to improve a rifles performance.

A Big THANKS(!) to Zimbabwe for taking the time to post pics and pass the knowledge along!


Best,
Dave

Yes, extra thanks to Mauser98 and Zimbabwe.

LWD