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Zastava/Yugo M77 magazine. In progress


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Ok, little update.   Follower tooling came back Friday late.. We had to run and get it right at closing time to have it over the weekend.   We have them rolling through right now, about halfway th

Saiga-12   Done Vepr-12 (design done) M77 - designing mostly complete Galil .308 (m77 based, likely to shuffle downward) Saiga .223 Catamout Fury-12 (saiga 12 based) Valmet .308 mags (low produc

We are making great progress on this project..   Metal for the body stamp plates is due in around a week. Testing has been very useful and productive, we had about 8 corrections to make and they al

Looks great, I will have to start saving up to buy a few.

 

Hopefully you still plan on making 5/10 rounders.

 

I was hoping that the stamping pattern would allow them to take M14 or AR10 followers, just so replacements or mods are possible. I guess I'll have to wait and see.

 

The reinforcement on the feed lip is a nice touch. I've noticed the M14 lips bend really easily.

Edited by mancat
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Yeah we still plan to make the full range of sizes. These magazines are fairly simple to make, so having a full range of sizes won't be as difficult.

 

Here is the front catch. Its really simple and should be much stronger than the factory magazines. Its the same size of metal but it wraps around the side of the magazine reinforcing it.

 

m77-for-web-4.jpg?t=1422241313

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Your baseplate design reminds me most of G.I. AR mags. Is that what your design is based on, and if so what alterations have you done? These look way better than M14 modded mags.

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We brought a few aspects of each design in. The AR magazine floor plates don't prevent spreading. Ours wraps the inside and outside to keep the body of the magazine stiffened on the bottom.

The big advantage is eliminating the tracks on the bottom of the magazine body, that allowed us to skip two steps on the body and have more lengths without have the "cut down" look of our current 5 round and 15 round mags. The magazine is also much smaller on the bottom than G-3 style floor plate, which means any of their pouches will work with a little wiggle room.

The design does require a retaining plate inside to spread the load to the front and back, but we had that part already to keep the spring aligned.

 

I'm not a fan of the M14 or AR-15 floor plate, its not really made to be disassembled to be cleaned with any regularity, and reliability hinges on keeping the magazines clean. Which is why all our magazines are easy to take down for cleaning.

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  • 2 weeks later...
So did a little shooting.. I'm pleased with how the M77 shot. Still can't get the Fury shotgun to work.... Almost used it as a target.

 

Mark the mill and tooling guy is the shooter for the video.. 

 

Shot a fair amount, no noticeable distortion on the magazine despite being in the soft state. We did have one stove piped case on the second round fired but the rifle is almost unfired so not really shocking. Looked like the extractor stuck a little and just released the case early. Did not happen again.

 

Noticed that ejection is erratic in the first few videos and starts to settle down toward the last couple, this video is in the middle at about 80 rounds.. Probably just the parts wearing in.. I'll be watching the later tests to see if it settles in.

 


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CSS,

 GOT APPX. 120-140RNDS DOWNRANGE; STILL EJECTING BETWEEN 1:00 AND 4:30, AS IT PLEASES.....

 

 NOTICING THAT MY GROUP SIZE EASILY DOUBLES WHEN FEEDING FROM FACTORY 10RND MAG vs. SINGLE LOADING FOR ACCURACY TESTING.

 

 GOING TO HAVE TO EXPERIMENT WITH MY CONCETRICITY CHECKER AND SEE IF BULLET IS GETTING KNOCKED OUT OF TRUE DUE TO BUMPS AND KNOCKS OF FEEDING CYCLE.

 

 HAVE YOU OBSERVED THIS, OR JUST MAINLY CONCENTRATING ON FEED/FUNCTION, AT THIS TIME?

 

  THANKS,

 JESS1344

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Zastava rifles are typically extremely tight out of the box, so not surprising.

 

I do not trust the factory mags at all, so mangling the bullet is a strong possibility. That's the main problem with the factory mags for these - they appear to use a hastily designed follower that tilts easily, allowing the round to feed either low or high, depending on what mood the magazine is in at the time. I keep meaning to crack open the factory mag and see if I can make an M14 follower fit. These rifles were supposed to be issued with 20rd factory mags with anti-tilt followers, not the little ones that we're stuck with.

 

Even if it knocks down the capacity by a few rounds, I would rather have a functioning lo-cap mag or two versus one that doesn't work and never gets used.

Edited by mancat
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The magazines for their .223 pistol are the definition of cheesy. They are thin, fragile plastic. Everything about them says "this is a placeholder for the magazine we know you are going to buy later." 

 

Sounds as thought the same is true for the .308

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The 10 round mag just feels off. I can't really figure what exactly is wrong with it other than its poorly constructed.

 

I have one of the original factory 20s and it is almost exactly the same design including the follower and it feels solid and feeds well. The 10s are just kinda crappy.

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Is the feed angle the same? Or maybe the whole round sits at the same angle but a hair lower?  Those seem like the most likely culprits for the projectile hitting the feed ramp, or conversely a sharp angle on insertion to the chamber, which Jess seems to be gettting.

 

Another thought for Jess's mags is soft plastic in the feedlips could be dragging more at the rim area and causing random rounds to flip up a little just as they are pushed clear of the feed lips.

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Ehh, the mag should blow out in the event of case separation. The pressure has to go somewhere. Last I checked a magazine is about $20K less then hand reconstruction, so its fine if the mag blows out.. This is why the locking tabs need to be stronger than the floor plate. It allows the force to be directed away from you.

 

I'd check the guns head space before shooting again.. If something is off it could get MUCH worse, have the gun checked by a competent gunsmith.. If something is wrong with the rifle odds are its correctable or at worst you can sell it as parts.. It could also be that batch of ammo as well, it may be wise to contact the importer as well, see if that is something they know of.

 

Having case head separation is NOT a good thing. It can be very damaging to guns and shooters.

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These mags could use a bolt hold open follower option. Actually after trying Primary Arms' x39 BHO followers, I'm thinking lots of mags could. Any chance of BHO followers for some of your mags? I'd gladly buy replacements for your 308 VEPR and M77 mags, I have, and hope to have,  if you run some in the future.big_smile.gif Don't know if R&D would be too much of a pain...

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It would require a different follower design.. We are supposed to make a run of M-14 pattern mags in the future that will have that style follower. On the M-77 it would require eliminating the rear follower stops in the magazine. It will leave two small square holes in the magazine but not large enough to weaken the body.

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It would require a different follower design.. We are supposed to make a run of M-14 pattern mags in the future that will have that style follower. On the M-77 it would require eliminating the rear follower stops in the magazine. It will leave two small square holes in the magazine but not large enough to weaken the body.

 

So removing the follower stops would let the current follower stop the bolt or would a new follower design be needed too?

 

Any Time frame? I'll stay tuned.

 

Almost forgot -- Are the 308 NDM 86 mags still a possibility???

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Six weeks or so.. I'll probably have mags coming off the stamp line in three weeks, but the finishers take time as well.

 

Springs are being made in Utah. Steel sheet is being cut in Minnesota. The bar stock is coming from Michigan to be milled here in FL..

 

Sample is making its rounds in the southeast.

 

I'm getting nine boxes of valves and timing hardware tomorrow to finish the controls out on the 'green line', its a self contained 12 station press that runs on a single 2hp motor rather than twin 10hp motors. I got tired of paying 17+ cents a kilowatt hour to heat my shop to 105* in the summer (maybe a slight exaggeration)... So I have a project for the weekend.

This line is for all the small parts, like three units are dedicated to follower forming, two for floor plates, one for the retainer, and another for the front catch. We have been using two presses but they run on compressed air and don't have the same cycle time due to the inefficiency of that system... I can run the parts in either setup, the new line allows for continuous operation without shutdowns to purge water condensate.

 

PS. I'm more of a machinery guy than a firearms enthusiast, with the business I get to combine all my hobbies into a single super obsession.. 

 

I have pictures up of a finished magazine.

http://stores.csspecs.com/zastava-m77-308-20-round-magazine-coming-soon/

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  • 2 weeks later...

Steel mag blanks are on the truck, should be here Wednesday..

 

Just finished the wiring on the press line about 15 minutes ago.. Need to load the programs and go through troubleshooting.

 

The press line would have been done a few days ago if not for having to do a rebuild on a rocker arm welder that we found for super cheap.. Had a dead contactor and timer unit, replaced from my spare part bucket in about two hours.. Had to make a new shorter pair of rocker arms as the long sheet metal shop pattern arms lost so much power, went with 1 1/2 copper bar as the length is reduced substantially.. Had to pull the water cooler apart as it was pretty plugged up. Its welding Vepr-12 rear lugs on as of this morning..

 

 

Edit for 3-22-15

 

Press line is up and running, had a couple program glitches that made it do something screwy.. And a wiring error that made the E-stop circuit not reset. I had it on the 9 instead of the 6, easy mistake when your looking at the box upside down. Took a little time to get those sorted out, but its up and running very smoothly. I'm very pleased with the unit at present.

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