Cz feeding problem

[Choupique]

I just rewatched the video.

The last round, you need to press the bolt forward SLOW and clearly show the case head to tell whats happening. The bolt hits the case exactly between frames (36 and 37 seconds IIRC) and theres no way to see what happens except the case launching out. Not bagging on you because I know you wanted to show whats happening, but it doesnt do any good for figuring out why.

The extractor is definitely pushing the round out but why its happening isnt possible to tell from the video.

 

[baxterb]

Those rails seem mighty wide to me. If you hand hold the cartridge in the “corner” of of the mag box under the rail is it in the same position as the follower holds it?

The problem will be found by starting from the ground up and comparing the dims to the stacked rounds (aka Mauser’s Rule) and working upward to the rails. The solution might not be a simple one.

Too many people start fiddling with rails to solve issues they aren’t causing and open Pandora’s box in the process.

Did this rifle start as a 458 Lott or was it converted?

 

[IvW]

Last round issue is follower issue.....does it have a 458 Lott follower or different cartridge?
On ZKK the cartridge is stamped under the follower not sure on 550...
If it was something else before(wrong follower) I would start there....

 

[Clodo Ferreira]

In the video the rounds look beat from feeding multiple times. He has to put quite a bit of force to feed all the rounds.

If it really is a Matrix rifle, can’t emphasize enough that talking to them is where I’d start.

Hi Mitch,

I see the same thing as Limb do. And the first thing I would do is, also, what Limb recommends: "If it really is a Matrix rifle, can’t emphasize enough that talking to them is where I’d start." Even if you bought the rifled second hand.

Looking, again, the video, I don´t see a weak follower spring, on the contrary I see perhaps a too strong spring, coupled with angles and polishing of the lips and of the extractor and left part of the bolt face . May be that too strong spring is the cause of the force to feed all the rounds...

Good luck!

CF

 

[AZDAVE]

@Ontario Hunter I have been looking for that booklet for a couple years. Where did you find it?

Also if anyone has one they are willing to part with I would purchase it.

 

[Ontario Hunter]

@Ontario Hunter I have been looking for that booklet for a couple years. Where did you find it?

Also if anyone has one they are willing to part with I would purchase it.

Back then Duane had a website. I think I heard he's winding down. If you can find his phone number, he's a really great guy to talk to. Gave me lots of encouragement and advice. Maybe check some of the gunsmith/machinists forums. Someone there might know how to get in touch with him. Good luck.

Let me see if there's an address on the booklet ...

 

[mitch4570]

Those rails seem mighty wide to me. If you hand hold the cartridge in the “corner” of of the mag box under the rail is it in the same position as the follower holds it?

The problem will be found by starting from the ground up and comparing the dims to the stacked rounds (aka Mauser’s Rule) and working upward to the rails. The solution might not be a simple one.

Too many people start fiddling with rails to solve issues they aren’t causing and open Pandora’s box in the process.

Did this rifle start as a 458 Lott or was it converted?

It was coverted to 458 lott. Not sure who did it.

 

[mitch4570]

Hi Mitch,

I see the same thing as Limb do. And the first thing I would do is, also, what Limb recommends: "If it really is a Matrix rifle, can’t emphasize enough that talking to them is where I’d start." Even if you bought the rifled second hand.

Looking, again, the video, I don´t see a weak follower spring, on the contrary I see perhaps a too strong spring, coupled with angles and polishing of the lips and of the extractor and left part of the bolt face . May be that too strong spring is the cause of the force to feed all the rounds...

Good luck!

CF

I am the 3rd owner of the rifle. It is really hard to get Matrix to respond.

 

[Choupique]

You could try adding layers of masking tape to the follower and see if it will alter the position of the last round favorably. At least that will give you an idea of what needs to happen. I bet adding about 1/8" of tape to the cartridge side of the follower sticky uppy part (,dont know what thats called) would change something. Modify from there.

Or, start grinding away at the extractor tip. I would want a really good look at how much would need to come off first though.

 

[mitch4570]

Good ideas. I will try this. I have springs coming in the mail. I stretched the mag spings out a bit and it feed perfect for 10 rounds. Then it was back to the same problem.

 

[spike.t]

Converted From 458 win mag?.....if so someone I know in the English gun trade....when I was asking him on behalf of a friend about rechambering a 550 to something bigger, he said do not use a 458 win mag one as the base as they are a nightmare and it will have feeding issues...he said better to use a 375 as the base to start with.....

 

[IvW]

It was coverted to 458 lott. Not sure who did it.

Mag follower check if it stamped on the bottom.....458 is the worst one.....needs to be reshaped

 

[mitch4570]

You could try adding layers of masking tape to the follower and see if it will alter the position of the last round favorably. At least that will give you an idea of what needs to happen. I bet adding about 1/8" of tape to the cartridge side of the follower sticky uppy part (,dont know what thats called) would change something. Modify from there.

Or, start grinding away at the extractor tip. I would want a really good look at how much would need to come off first though.

So if adding an 1/8 inch of tape make things work better, were to go from there can't add material to the follower. I am going to try this anyway.

 

[BlueFlyer]

I have springs coming in the mail.

Enfield M17 springs are designed for a deeper magazine, so are a good way to increase your spring rate. Little bit of Dremel work might be required to make them fit.

 

[Choupique]

were to go from there

You would know that you needed a new follower.

It could always be redneckerized. You could spot weld a 1/8 shim to it or something crazy like that. Im sure theres a commercially available follower somewhere in the world out there that would fix it though if the follower is jn fact the problem.

If nothing else with the prevalence of 3d printing, someone could print yiu a plastic one.

 

[BlueFlyer]

It could always be redneckerized.

An 1/8" strip of metal on the shoulder of the follower - could be silver soldered and screwed.
Another way is to add material to the opposite side of the of the follower, so it kicks the follower across in the magazine box.
Many ways to skin a cat! I prefer the first option, once you determine how far you need to build it up. The beauty of the tape idea is that you can just slowly build up the tape and try it with every strip of tape added until the feed is reliable.
As you move the last cartridge across in the magazine you also need to check the round above it as that relationship will be changed.

 

[Ontario Hunter]

So if adding an 1/8 inch of tape make things work better, were to go from there can't add material to the follower. I am going to try this anyway.

Now you know what width follower you need. Contact New England Custom Gun and see if their magnum followers are wide enough. Too wide is not a problem. Trim to fit. That's what I did to make one fit my 404 project. May need to shape the new follower guide to make it release the last cartridge at the right time.

 

[mitch4570]

Here is a pic of how the CZ is marked I believe this rifle was chambered in factory as a lott. I tried masking on the follower 3 layers on the bolt side back half of the follower. Loaded single round 15 time worked correctly ever time. Loaded 5 round cycled them through no problems last round fed fine

 

[mitch4570]

Oh forgot to say the 3 layers were .012.

 

[mitch4570]

Mag follower check if it stamped on the bottom.....458 is the worst one.....needs to be reshaped

No markings on the follower.