L3I CZ Mags

[USMC22]

Got (2) L3I Magazines in the mail today. Feel solid, load easily and fed properly when FULLY seated. They are a TIGHT fit which require holding the mag release and actively PULLING on the magazine itself to free it. I'm using the DIP, Inc. Magwell. When I get more time may try it with the OEM Magwell to see if its still as tight.

Anyone else get there's yet?

CZ 13 Round Billet Magazine – L3I Design Solutions

l3idesignsolutions.com

UPDATE: I installed the CZ OEM Magwell. Better fit and MUCH MUCH easier to remove.

When the magazines are loaded to capacity, 13 rounds, it is not possible to seat the magazine while the bolt is closed.

The magazine will seat with the bolt open but it is firm and first round feeding has been hit or miss.

The magazine will seat on an open or closed bolt when loaded with 12 rounds.

I did not experience any first round loading issues when the magazines were loaded to 12 rounds.

The first round feeding issues were consistent only when the magazines were loaded to 13 rounds.

Firing 225 rounds tonight I have ZERO feeding issues other than the first rounds when loaded to 13 rounds as stated earlier.

The magazines fit and finish look awesome and I like how they stack together nicely in the range box.

Overall I think these are a huge win to the CZ market as long as they are kept to 12 rounds.

 

[ARShooter91]

Mirrors my experience other than the first round feed issues. Mine have been loaded to the full 13 most every time and load perfect.

What exactly happens to yours?

 

[USMC22]

Mirrors my experience other than the first round feed issues. Mine have been loaded to the full 13 most every time and load perfect.

What exactly happens to yours?

Round doesn't chamber / gets stuck below the chamber. It pops out of the mag and doesn't ride up in to the chamber.

ETA I'll try to get a pic of it next time

 

[1911Shootist]

I got 2 as well. They fit and feed fine in my basement testing (OEM mag well & ACC chassis). They are a touch wider than OEM plastic and steel mags, I had to redesign my 3D printed mag pouches for them - added ~0.3mm in both directions. First match with them is today

 

[USMC22]

Pictures added. Got a video but fighting with the GoPro to upload it.

 

[USMC22]

1st round feeding w/ 13 rounds


1st round failure to feed with 13 rounds

 

[1911Shootist]

I got 2 as well. They fit and feed fine in my basement testing (OEM mag well & ACC chassis). They are a touch wider than OEM plastic and steel mags, I had to redesign my 3D printed mag pouches for them - added ~0.3mm in both directions. First match with them is today

Both mags ran perfectly during the match today. They feel great, spring tension is just right, and it’s slightly easier to hit the mag release tucked up in the ACC magwell. Well done L3i

 

[Thesepaperwings]

This is so awesome to hear! The first round acting up is weird so let me know if that continues

 

[ARShooter91]

Ran a few more testing a new case of SK STD+. Ammo was better than I expected with accuracy and ES/SD. Mags were flawless again from the full 13 to empty.

USMC22
Idk why but I wonder if it has anything to do with your rifle being a lefty. What ammo?

 

[USMC22]

This is so awesome to hear! The first round acting up is weird so let me know if that continues

Will do. Hoping it’ll “break in”

No issues with regular cz mags on first round.

 

[USMC22]

USMC22
Idk why but I wonder if it has anything to do with your rifle being a lefty. What ammo?

In the case of a magazine that is not left hand specific, I.e. a Ruger 10/22 custom left hand, that takes left hand specific magazines it shouldn’t matter.

As for ammo SK rifle match, long range match and lapua center x to start. I have a bunch of random lots laying around I was looking to shoot off. After that I switched to cci sv for testing the magazines and trying to diagnose the issue.

 

[USMC22]

@Thesepaperwings when testing the beta version did you find feeding issues with the first round due to spring tension / binding?

 

[Thesepaperwings]

Nope, in theory the presentation angle should be the same throughout. I have a 457 manners mtr, 457 varmint with dip magwell, 455 manners with lrp barrel and a 457 with dip magwell and grey birch chassis/barrel. All were used for testing

 

[Norman1950]

I just ran a match with my 2 L3I magazines. For the most part they ran pretty good. I did notice that with them being a longer than factory, I had a magazine pushed up against my support bag and wouldn't feed. Believe I need to get one of the gray ops barricade stop now to make sure this doesn't happen again. Overall I am very happy with the way they fed the rounds.

 

[USMC22]

I want to preface these videos by saying I’m not an engineer. The majority of folks having received these magazines are not experiencing the same issues which means it could be ammo, my cz a combination of the above etc. I’ve had issues with CZ magazines in the past and just tossed them in to parts bins. I do not have the same failure to feeds with my working CZ magazines. That said I don’t have the time to go film every one of them along side these.

The magazines look great and when they word are awesome. They are not 100% for me, but in rimfire 100% is usually cherry picked or an outlier.

Mag would not load to 13 rounds. Rattling when shook. Similar to CZ mags in the past which have had a faulty spring or follower. Usually this was remedied by inserting a pin when loading the magazine, trapping the spring and releasing it when the magazine was empty so it could "slam" into place.


Magazine issue maybe rounds locked by rims? Failure to feeds.


CCI SV feeding, no issues this magazine?


possibly isolated to one magazine now


“Offending mag” ran with CCI SV


SK Match in “problem mag” runs flawless


SK Match in “offending mag” jams

 

[ARShooter91]

Is your bolt interfering with the mag of the mag/top of the feed lips? Or vise versa.

L3I can be inserted deeper than factory. Hasn't caused me any issues though. It might be exaggerated in these pics as when loaded in the rifle they look pretty flush.

L3I

CZ poly

 

[Thesepaperwings]

I'm going to bet that one of your followers got tweaked.

 

[USMC22]

I'm going to bet that one of your followers got tweaked.

Have you got a reference of a good one to compare? Able to be remedied?

 

[Thesepaperwings]

It actually uses a version of the factory follower that we recreated so if you toss in a factory follower and it runs well then that's the answer. You can tweak the follower by bending it slightly but not sure how comfortable you are with that since it's kind of a weird art form of troubleshooting that guys used to have to do with steel magazines lol.

 

[USMC22]

It actually uses a version of the factory follower that we recreated so if you toss in a factory follower and it runs well then that's the answer. You can tweak the follower by bending it slightly but not sure how comfortable you are with that since it's kind of a weird art form of troubleshooting that guys used to have to do with steel magazines lol.

that sounds like a project. Other than the follower do you have any ideas?

I don't mind running it for now and its marked but, if it keeps being a problem or gets worse would you mind swapping it out?

 

[Thesepaperwings]

We stand by our products. Send [email protected] an email. Depending how you marked it I'll swap it with a new one (I'll even video it running) or I'll tune it and ship it back if the body is marked up

 

[USMC22]

We stand by our products. Send [email protected] an email. Depending how you marked it I'll swap it with a new one (I'll even video it running) or I'll tune it and ship it back if the body is marked up

thanks, sent an e-mail and marked the mag with tape so I could remove it

 

[USMC22]

@Thesepaperwings I put another 300 rounds through them this afternoon. I'll say my CZ and / or mags hate Lapua Biathlon. It did not want to feed them until a lower round count was obtained; each getting stuck the way I photographed above.

SK Match was about 95% with the top 1-3 rounds being 100% of the problem.

CCI SV similar results.

I won't have any more time until Thursday to shoot but I'll try Lapua Center X, CCI Mini Mags, some Aguila.

Edited: thanks @Thesepaperwings

 

[Thesepaperwings]

April added it to our tasks so you'll be good to go soon. I'm going to disassemble it as well to make sure there's feedback here on things that can happen in mags.

 

[mikeshaw2]

on a happier note: both my L3i mags ran flawlessly yesterday, 10 rounds, 12rounds, 13 rounds all worked.

457 with a DIP magwell, AoD extended mag catch, in a KRG Bravo.

I haven't met a 13 round stage yet, so I'll probably just load to 12 and call it good

M

 

[USMC22]

April added it to our tasks so you'll be good to go soon. I'm going to disassemble it as well to make sure there's feedback here on things that can happen in mags.

Awesome! Thanks again!

 

[AR15-SBR]

Any word on the availability of the10 round mags?

 

[USMC22]

Sent one of my mags back, looks like it arrived yesterday. Hopefully it’ll help diagnose what the issue was and I’ll have another mag on the way soon.

 

[TrevK]

Neither of mine will grab with 13 rounds loaded on a closed bolt, but they run fine and can be loaded into the gun with less than 13 on closed or open bolt. Have to start a stage with an open bolt anyways, so not a huge deal.

 

[USMC22]

@TrevK I hear you on the rules, it was just an observation. My old mag made it back to L3I and @Thesepaperwings and a new one is en route. Would like to know what was going on with the mag after they check it out.

unfortunately I haven't had a chance to send some rounds since.

 

[TrevK]

@TrevK I hear you on the rules, it was just an observation. My old mag made it back to L3I and @Thesepaperwings and a new one is en route. Would like to know what was going on with the mag after they check it out.

unfortunately I haven't had a chance to send some rounds since.

Hopefully they get you sorted out. I neglected to mention I’m running a box stock 457, so no custom barrel or bottom metal affecting mine.

 

[USMC22]

Hopefully they get you sorted out. I neglected to mention I’m running a box stock 457, so no custom barrel or bottom metal affecting mine.

mines stock too minus bolt knob and action screws. I swapped the aftermarket Magwell out, that only alleviated the tight fit, too tight.

 

[USMC22]

Anyone else get some more time in with their mags? I got 300 rounds in today with some center x banging steel. . . the magazine I didn't send back is not cooperating when loaded to 13 rounds (ETA: of Center X). It's basically a 10 round magazine for me with the same issue each time of the round not being sprung up into the chamber. 4 other CZ mags, no issues (2) 5 rounders and (2) 10 rounders.

 

[ARShooter91]

I have about another 100rds through each still with no issues.

 

[TrevK]

I’m going to put a few hundred through mine this weekend to further test

 

[USMC22]

Got the new mag, same issues, worse with Lapua Center X which is what I primarily shoot. Ok at 10 rounds or less. Tried other ammo, CCI SV, Norma Tac, Aguila = same.

 

[ARShooter91]

Message sent with an idea USMC22

 

[USMC22]

@ARShooter91 is going to try the magazines out. Shipping them out to him tomorrow after I get the address. Interested to see where his mags are running clean.

 

[ARShooter91]

I can try CCI SV, Norma, Aguila, and Lapua LR. I'll start with SK STD+ as that's what I usually shoot in the 457

 

[USMC22]

perfect, thanks

 

[ARShooter91]

Bought a second CZ 457 with dip magwell and block. Mags work fine, a lot more play than with my new DIP parts. They appear to be an older design on the CZ I just picked up. So the new DIP parts are what is causing the L3I mags to be super tight.

 

[USMC22]

Bought a second CZ 457 with dip magwell and block. Mags work fine, a lot more play than with my new DIP parts. They appear to be an older design on the CZ I just picked up. So the new DIP parts are what is causing the L3I mags to be super tight.

Those CZ's seem to multiply

 

[TrevK]

Put a couple hundred rounds down range in the CZ yesterday. The new mags were inconsistently backflipping a spent case into the chamber. They work fine and I’m not upset about anything, but I won’t run one in a comp.

 

[ARShooter91]

Those CZ's seem to multiply

Well it was a smokin deal and he was local, what choice did I have lol

I should get your mags tomorrow so I'll have another gun to try them if I have issues or if not.

 

[USMC22]

@ARShooter91 its hard to pass on a good deal for sure, local at that.

Sounds good on the mags. Will be nice to see if they run clean or not!

 

[ARShooter91]

Alright. Preliminary results are good. Loaded both to 13 with Norma tac. Slowly pushed the first one in and on the second mag harder and faster. All 13rds cycled perfectly.

Next I loaded them to 13 again with my preferred SK+ and shot these to check zero and go after some spinners at 100. Again slow and soft on the first then fast and hard. I alternated back and forth while shooting. 100% again. No snagging or chipping of the bullet.

I'll cycle some CCI and Aguila through it. Then I can shoot some Lapua although pretty sure if SK went fine it will as well.

Edit: laying one of mine and USMC22s on top of each other they look identical. Feed lips, follower shape and angle the same.

 

[USMC22]

@ARShooter91 looking like it might be my rifle / magazine combo.

 

[ARShooter91]

Aguila SV 100% and I did get one CCI SV to catch. It was the first round of 13, no issues with the other 12 or trying 13 a half dozen more times. I think it has something to do with the nose of the CCI. It's not as round as the SK, Norma, or Aguila.

 

[ARShooter91]

@USMC22
How much vertical play did you have with a mag inserted?

 

[Thesepaperwings]

If anyone happens to take their rifle apart can you measure the opening width of your ejector plate and the width if your mag opening on the action body itself? I've got 5 rifles in house that we use for testing and so far the smallest opening has been the ejector plate. Well, the smallest is if someone tightens the barrel without the ejector plate being centered since it has play before you tighten it down.