CZ feed issue

[Neil Molendyk]

Had a hell of a time with my .458 Lott and Hornady DGS. I was told the easiest thing to do is just stay away from them. Barnes VorTx.

I had the same issue with my CZ 550 in 416 Rigby. Swift A Frame and Swift Breakaway solids worked flawlessly

 

[csmiffy]

That side cutout i reckon should be there. That is where the case starts to leave the side rails and pop up into the extractor. my personal thought is the projectile is hanging up on the side. The projectile only has a small distance to go before it starts to hit that and it's way less than the relief I just mentioned. You mentioned that spitzers don't have an issue? That will be because the ogive is further back and letting the whole case come forward more to do its thing. At the moment the projectile is hitting the side as it comes forward pushing it down.
How does it compare to the other side? If that is fine, look to see how the projectiles interact with that and see how much clearance it has
Just my thoughts of course. Some very light polishing certainly cant hurt and if that doesn't work and you arent confident about doing the rest yourself, definitely take it to a good gunsmith

 

[Scott CWO]

My Lott fed some bullets/ammo but not others.

Why mess around? Send to Matrix or someone else qualified and you guys would have rifles that feed anything.

 

[Hunter4752001]

I have a Brno 602 (predecessor of the CZ 550) which is now in 458 Lott . It always had feeding issues. I was almost resigned to it being suitable only for RN solids or ultra pointy designs. I did notice that the problem was always on feeding from the RH side of the mag, the cartridge pointed directly at the LH edge of the chamber, where it subsequently jammed. Fortunately I have two other 602's, a 300 WM and a 375 H&H. In one of those rare moments of clarity I decided to test if it was a follower problem creating the wrong geometry for feeding. I removed the followers from each of the rifles, (first marking them as to which rifle they came from). I noticed the 300 & 375 followers looked identical whereas the follower in the 458 was very different. Swapping them around, I found that the 458 cartridges now point directly down the centre of the chamber. Runs like a sewing machine irrespective of projectile shape (including very flat point 45-70 type projectiles).

Back in the day, Mauser took great care to ensure that their followers matched the cartridge for which the individual rifle was built. I doubt that many manufacturers today take that level of care, generic fit at best.

This may or may not be relevent to your rifle, but may be worth trying if you have the chance. The good thing is that no metal needs to be removed. Failing that, don't muck around, just send it to a specialist DG rifle smith such as Matrix. When talking dangerous game, gunsmith costs are way cheaper than medical/hospital costs.

 

[csmiffy]

That is a very good point, @Hunter4752001 as well as Parker Hale had something like 14 different profiles for the feed rails.
I had a minor issue with a Brno Mauser 8x57 sporter. It still had the pressed tin follower and on the very last round it would get all knotted up. After trying some stuff and other followers, i found it was the follower tipping slightly on the very last case and getting all stuck between the mag box, feed rail and case. Different pressed tin follower (from a mates rifle) with narrower sides worked fine. I did some creative metal work on mine and that worked but I had already sourced a sporter metal one and used that instead.
@VonGruff did a very informative post on here concerning ammo stacking, heights and such to work out the optimum. Wasn't really my issue but could be well worth a look in your situation

 

[Scott CWO]

I have a Brno 602 (predecessor of the CZ 550) which is now in 458 Lott . It always had feeding issues. I was almost resigned to it being suitable only for RN solids or ultra pointy designs. I did notice that the problem was always on feeding from the RH side of the mag, the cartridge pointed directly at the LH edge of the chamber, where it subsequently jammed. Fortunately I have two other 602's, a 300 WM and a 375 H&H. In one of those rare moments of clarity I decided to test if it was a follower problem creating the wrong geometry for feeding. I removed the followers from each of the rifles, (first marking them as to which rifle they came from). I noticed the 300 & 375 followers looked identical whereas the follower in the 458 was very different. Swapping them around, I found that the 458 cartridges now point directly down the centre of the chamber. Runs like a sewing machine irrespective of projectile shape (including very flat point 45-70 type projectiles).

Back in the day, Mauser took great care to ensure that their followers matched the cartridge for which the individual rifle was built. I doubt that many manufacturers today take that level of care, generic fit at best.

This may or may not be relevent to your rifle, but may be worth trying if you have the chance. The good thing is that no metal needs to be removed. Failing that, don't muck around, just send it to a specialist DG rifle smith such as Matrix. When talking dangerous game, gunsmith costs are way cheaper than medical/hospital costs.

That’s exactly what my CZ Lott did until AHR fixed it.

 

[fourfive8]

^^ Yep. The easiest thing to change and try without doing something irreversible is the follower. I discovered that when lengthening a standard Win 70 action to "magnum" length so it would feed longer cartridges smoother and more reliably.

The geometry is tricky with BRNOS and CZ 550s as the cartridge has to "jump over the hump" as it negotiates the transition from the lower magazine plane to the higher plane of the chamber axis. The design seems to have more of this jump than some other actions. The bullet hits the ramp then the whole cartridge has to jump up and over the ramp as it re-aligns itself to enter the chamber with the bullet, hopefully, more or less centered in the chamber opening. All the while the cartridge is being held against the bolt face by the extractor. Really quite a chain of events! I took some slow-mo videos with my camera once just to watch all the gyrations and sequence of motions a cartridge goes through during the process. It was educational.

 

[mark-hunter]

I noticed the 300 & 375 followers looked identical whereas the follower in the 458 was very different.

Can you put photos of each follower if still available?

 

[Hall]

Had a hell of a time with my .458 Lott and Hornady DGS. I was told the easiest thing to do is just stay away from them. Barnes VorTx.

Cycle some cases through and post a picture of the head stamp afterward please. As was mentioned, it’s a good place to start.

The VorTx feeds like a dream, as do partitions, and now A frames also. I appreciate your suggestion.
Thank you to everyone who's contributed to this thread, I have learned some things and for that I'm very grateful.

 

[Nhoro]

I have a cz 550 and spent many hours getting flat nose solids to feed properly. Please check something for me- look at the end of your bolt. There is a collar that encloses the top of the case and it ends in a chamfer on the left side. Check if the end of the collar is sharp and if it is catching or pushing on the case just as it jams. The case has to come off the feed lip and up that edge to feed correctly. Secondly, polishing the feed lips with 400 and then 600 grit sandpaper will also help the cartridge come up and oit of the magazine a little earlier. Worth trying a little polishing before you send it to a smith. I will try take a pic or 2 tommorrow and post.

 

[IvW]

And then some folks say Old ZKK and CZ are the same... never had issues with any of my ZKK's...

 

[Hunter4752001]

Mine is a ZKK but I can't guarantee that some previous owner didn't f*k around with it. Its been a long time (decades) since any of us were able to put our hands on a fresh from the factory brand new ZKK! That means any bought now have been through at least one previous owner and at any time subject to tinkering or even cannibalizing.

 

[CBH Australia]

They are factory PPU 300gr round nose. Bought some dummy rounds off of Amazon and it'll unseat the bullet and push it into the case before it'll feed.

My .458wm didn't feed well if I was reloading quickly but was ok if I went slowly.
My
375H&H seems to feed well with the same ammo but it hasn't been taken out much.

I've read plenty about having the smoothed up, polishing feed rails etc.

They are a commercial action, like Remington, Tikka and others there is always room for improvement. I think they are still a good starting point for many of us.

 

[Hall]

They are a commercial action, like Remington, Tikka and others there is always room for improvement. I think they are still a good starting point for many of us.

I've yet to feel an action smoother than my tikka

 

[CBH Australia]

I've yet to feel an action smoother than my tikka

All of my Tikkas are smooth, My CZ550, smooth enough, but it could be better.

Tikka, like Remington has numerous aftermarket parts available. Some I consider upgrades or others are just changing the form or functionality.

Tikkas are modular allowing a lot of changes in configuration.

Tikka are accurate. The Tikkas that I had rebarrelled are more accurate than they were with factory barrels.

 

[Nhoro]

Make sure this edge on the bolt is radiused and polished.For feeding problems i recommend you use dummy rounds. You should be abke to look back into the action and see if this little edge is causing a problem. And then if your feed lips are rough, it will prevent the round popping out- similar to what you describe. Very fine grit sandpaper from 400 to 600 are safe to just polish the underside and edges by hand. Lastly, look at the front of the magazine- where your bullet is hitting and sticking- that area can be gently polished to make it slightly rounder. The CZ's often have some sharp edges and rough corners which dig into brass. A little work polishing and they clean up well. If you are worried then get a smith to polish it up for you.

 

[Nhoro]

You can check out my post on the work i did or pm me if you want more info. I have some hard earned info on the mauser feed system . My brain still aches ! https://www.africahunting.com/threads/mauser-action-feeding-work-cz-550.47094/