if i can find a source for springs, would anyone be interested in a 40 rnd mag?

I received my test magazine the other day and have done some testing with dummy rounds to check feed angle and bolt to case head engagement.

Some background info - I have been modifying magazines to fit Valmets going back over 25 years and have spoken with Tony Rumore (Tromix) when he was doing mag modifications, and I know first hand how difficult it can be to get right.

It is all about getting the feed angle correct and making sure there is sufficient bolt to case head engagement. The feed angle needs to be such that the tip of the projectile enters the chamber directly, since there is no barrel feed ramp - get the angle wrong, ie. too low, and you run the risk of pushing the projectile back into the case as it bounces off the lower face of the barrel.

Get the locking lug engagement wrong when trying to adjust the feed angle such that the rear of the magazine is sitting too low, then you get minimal bolt to case head engagement and the result is a bolt over base malfunction.

So now onto the test magazine that I received.
1) It fits TIGHT! No side to side wobble in my mag well. It is so tight, that a fast magazine change is impossible. The front lug needs to be engaged just right and the mag needs to be inserted perfectly straight relative to the mag well or there is no way you can rock the rear of the mag into engagement. I recommend thinning out the top forward portion of the mag by a few thou - makes it easier and faster to insert the front of the mag and you should still be able to minimize any side to side play.

2) Cycled some dummy rounds. One round in the mag only was fine - feed angle was a little low, but safe. I also noted  that there wasn't much of the bolt engaging the case head.
Putting 2 rounds in the mag, I got consistent bolt over base malfunction due to very little or no bolt engagement of the cartridge. Checking the follower, there was a small amount of tilt, however, that was not the root cause.

Here is what I observed: the back of the magazine is too low, resulting in a bolt over base malfunction where the bolt misses the case head. Field stripping the M-76 and then inserting the magazine into the mag well, you could clearly see this.
I suspect the mag was made this way in order to get the feed angle correct.

However, in Valmet 223/5.56 rifles (or any 5.56 AK), the mag feed lips need to be tucked right under the rails and parallel to the rails in order to get the bolt to properly engage the cartridge.
In other words, the test magazine needs to have the locking lugs set lower so that the mag sits higher in the mag well.
How do you do this, while maintaining the feed angle?  Isn't the rifles' ejector in the way?
The answer is to add a relief cut to the left feed lip so the magazine can sit higher.
Factory Valmet mags don't have this since the lips are a single steel sheet with very thin reinforcing relative to a 7.62x39 AK mag, and are thin enough for the mag to sit high in the mag well.

On modified East German Weiger or Bulgarian Circle 10 mags, there is reinforcing metal or added polymer that adds thickness to the feed lips. If you look at a Tromix modified magazine, you will find the left feed lip relief cut to allow the mag to sit high enough for positive bolt engagement of the round.
As another example, take a look at the feed lips of a Serbian Zastava M85/M90/M95 5.56mm magazine. They have the classic AK reinforced feed lips, but they too have a relief cut from the factory on the left feed lip that is there to provide clearance to the ejector.

If you lower the lugs a little and add the left feed lip relief, then this would give a much more reliable feeding magazine.

Hope this information helps.

Mick

I could care less about the haters of TAPCO.

I use the TAPCO Sten mags and they work for mines just fine, the DLO STen, Lanchester pre may and my m11 Sten conversion.

They work and keep on working.

Not really, I like the size of the 30 round mags.

I just got home from a trip. It fits in my M71 really tight, but nice. Bolt rides over the feed lips perfectly. Ill get pics up in a bit.

xh63IJmzRCqpjqpAbzTg3A by Austin Scott, on Flickr

have loaded it up and checked function in rifle.  fits very snug, which I like.   don't like mag wobble.  should loosen up just a bit with use coming in and out.  want to get a few mags thru it to see if follower gets less sticky.  although it really barely even is at this point.

saw your message abut possibility of 40 rounders.  I think I would be more interested in a tanker 20 round mag, or even a 10 rounder.  something to help make bench shooting easier.  these look great so far and I appreciate you taking the time to do R&D and get these out to people.  perhaps even a hunting mag,  with round restrictions for your area's hunting laws, maybe 3 rounds or 5 idk if people would even hunt with their Valmets.

thanks!

Just got back from the range and I was able to put 225 rounds through the magazine before the cold got to me.  Before I started live fire, I loaded 10 live rounds and cycled them through the rifle and checked them for OAL. No change which confirmed my test run with some dummy rounds I'd loaded. I then loaded it with 5 rounds, then 10, 15, 20, 25 and 30 and then I finished the test with fully loaded mags. The rifle with the test mag ran flawlessly.

Attached are a couple of pictures of the mag. The first shows powder accumulation on the front and the second picture shows some very light wear on the right hand feed lip that it picked up during shooting. It might have had a slightly rougher finish at that spot. I didn't notice any wear there during dry testing. My only minor complaint is that the body could stand to be about .004" to .006" thinner. That would make it easier to insert and extract from the rifle.

I'll take it out again when the weather gets a little warmer and put at least another 300 rounds through it. Looks good so far.
Instead of 40's in the future, I'd like to see 10's and 20's.

Seriously, and the price point of the Tapco magazines are fantastic.
The feed angle is fantastic
the only draw back is a little wobble, but not like the steel galil mags

Hello all. I made the mistake of volunteering to be a mag tester but will not be able to test the mag I received for some time to come (long story). If someone would like to receive this mag for testing please email or PM me your address and I will forward it on immediately. You can then give your results to the OP as intended. His instruction to me was to shoot it until it fails. He also mentioned this mag is the last mag he sent out, and as such it was one of the fuglier ones, made using a different "print head". I am sure Regal_T-type can fill you in on this mag, but it looks great to me.

My sincere apologies to Regal_T-type and the community for jumping the gun on this.
Thanks,
Tall

I'll give it a good thrashing!  IM sent with shipping info.
Thanks!

the fugly one used a larger print head, to attempt to speed production. it has some melt damage but should function fine

Thanks AllAlphas! Mag is shipping today priority mail, you should get it Friday. Check your PM for tracking.
Sorry again for this mishap Regal_T-type, hope this mag gets fully tested and you get the feedback you deserve. Thanks again for making these. This one may have a few marks on it but it looks damn good to me, very impressed.
Tall

Thanks for passing it along TallPine.  
There's a very good chance it will be getting a test to failure at Cola Warrior West 5!  Cola Bros regularly break anvils and have plenty of 5.56mm to shoot up before heading home...

after you're done shooting, I'd like some drop tests done please.  fully loaded mag, dropped from chest height onto concrete.  I need to make sure the baseplate can handle the impact.  Also running it over with a truck would be a good test :)

In other news I am making final alterations and the mag should be available for sale this summer.  Thank you everyone for your interest and input!

Good luck with it.  The only thing that's kept me from Valmet is mag availability. If you solved that, I might rethink getting one.

I need a volunteer with a full auto to test an improved prototype.

I'd be happy to...but it's gotta feed better than your first prototype I got and it needs to have better locking lugs as well.
Went to get some pics of the mag with one of my Valmets...
Attached File

and when I went to insert the new mag for a pic this happened...
Attached File


Those locking lugs have got to be solid, or preferably made with steel inserts...especially with the somewhat brittle plastic you used in this one.

As far as feeding goes it was refusing to feed reliably from the right side, repeatedly sending the round high and to the left of the chamber when I hand cycled 3 or 4 partially loaded mags thru it.  You can also see in the second pic that rounds on the left side were hitting the front of the mag and quickly wore a U shaped groove in it.
Mag was also tighter in my mag well than necessary...it could stand to lose a few thousandths.
It's a good start but still needs some refining...

Test magazine locks up nicely, no issues empty cycling the bolt.

I then proceeded to hand cycle some dummy rounds. I was only able to get the bolt to grab a fresh round off of the top once. The remaining attempts either completely passed over the round or resulted in a failure to feed jam. I then switched to a factory mag to ensure that it was not my rifle. I think the feed lips might need a tad less material at the back in order to present the rear of the case to the bolt, but this modification could lead to issues with the bullet being aimed directly into the chamber.

Thank you all for the feedback!

I apologize for the delay as I had to build a new pc.

The mag has undergone several changes to address issues that arose in testing:

Feed lips redesigned to stiffen them and prevent rounds flying out the top.
Front and rear lugs improved to strengthen them.
Feed angle corrected.
Top of mag narrowed to ease insertion.
Over-insertion shelves added, this should cut down on wobble as well.



If you are interested in taking the plunge, I am ready to start taking orders for these mags.  Limit 1 per person for the time being.  75$ per unit.  Email me at [email protected]

Any update on this project?  I've got an M76 inbound

I would be interested.

I have one mag for my M76.

This is exciting.

What’s the status of this project? Did we ever get to production?

Any update? Very interested in this project

Any mags yet?  I would love to have one when they are ready.

I'd be in as well and will toss some good cash at this.

email sent just waiting for reply

Any updates?

Is this product dead or?

I know I'm a few years late here, just wondering how this worked out

With Tapco out of business, it would be nice if someone made a mag that would work in the ATI Galeo rifles.

Do regular mil spec / surplus galil mags NOT work in the ATI guns?

Like all US made galil receivers, the ATI are hit and miss.  I have a hand full of ATI receivers, some wont accept any mags, because the mag well was not machined to spec.  No big deal if you have a mill (or are handy with a dremel)  but once the mag well is in spec (compared to IMI) yes, surplus galil mags work in ATI's.

As for this Valmet mag project, your design is missing the most important component of the .223 valmet mag....the front lip of the mag acts as the bullet guide and ramps the cartridge to the chamber. (the galil uses a thick bullet guide to do this)  Without it you are going to have rounds slam the sides of the barrel and force the bullet back in to the casing...maybe just occasionally, but it will happen.  Otherwise you could just use a 14.95 surplus galil mag in a valmet.  The valmet has a what looks like a bullet guide, but it is thin and the bullet never touches it...the only thing that touches it is the the left rail portion of the bolt, to initiate bolt rotation.  A valmet .223 mag will actually fit a US imported IMI galil, and actually feeds the bullets better than an IMI galil mag (IMO)...but the bullet will not touch the bullet guide (even the thicker galil bullet guide), because the front edge of the mag is doing its job.

I hope this is not the end of the road for this project.

Again another post in hopes this project isn’t dead.  Received an M76 for my birthday, and in need of mags.  Hope all is well!

I know this is blasphemy but has anyone tried “installing” feed ramps into an m76?  

I had that idea...even picked up a cheap m71 to try it out..  Here is the problem.  Galil barrels are alot easier to remove than Valmet, and the barrel needs to be removed to install a galil bullet guide.  To remove the valmet barrel you have to drill out the upper rivet, then unscrew the barrel.  then drill out the bullet guide rivet.... I am not sure if the valmet bolt will clear a IMI  guide...the bottom of a valmet bolt is square not round like a galil....

The easiest and cheapest way to do it is just weld a ~1/8 strip of metal across the front of a galil mag.  I am going to have some lazer cut that have tabs on eacy side, basically once they are cut, you bend and spot weld the tabs on each side of a galil mag.  When done it should feed a galil or valmet...Galils that have the same mag well  spec as the galils that were imported to the US in the 80's.

I just picked up an M76, love the rifle but didnt come with an original magazine. It has a modified Circle 10 .223 mag. Im gunna play around with some of the commercial 5.56 mags to see if I can modify any slightly to work good with my rifle. Id love to try a 3d printed mag. Thats a very neat way of doing it!