S9 12rd. Mags Revisited

Discussion in 'Maintenance / Tweaks / Technical Difficulties / So' started by Max, Jul 3, 2006.

  1. Max

    Max New Member

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    ok. ive done some research on the 12rd'ers with some luck, but still have some questions. i'm gonna start from scratch, so please excuse my ignorance.

    1. does steyr make or sell stock s9 12rd. magazines? if not, they should. anybody know if they're gonna be making them in the future if they don't already?

    2. what is the difference between the followers, baseplates, springs, and magazine bodies for all steyr mags? i.e. m9 14rd, s9 10rd, s40 10rd.

    3. could i make a 12rd'er from existing s9 10 rd mags? just replace the baseplate with an m9 14rd baseplate? (if the baseplate in the s9 mag is taller.)

    4. are the followers in 9mm mags different from .40 caliber mags?

    5. to those who have done it, what does your s9 12rd mag consist of? i.e s40 mag body, s40 spring, m9 baseplate, s9 follower.

    im asking this because im horrible at altering feedlips. i have a tendency to overdo it. :roll: id love to find a way to do it without altering anything except swapping parts. HELP!! :(
     
  2. MrApathy

    MrApathy Active Member

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    just use a S40 mag though last I knew they were in short supply.

    no idea what magazines steyr is shipping with the S9A1 I would be happy to check it out for you and anyone else if they would cover the cost. :D

    havent checked differences in followers dont recall seeing anything too different.

    baseplates wont do anything due to the design.

    could you make a 12rnd S9 mag out of 10rnder no nor a M9 mag.
    M9 mags will work in S9 should be no different for S9A1's.

    tendency to overdo it? have you tried it with a steyr mag yet?

    one thing that may be needed is someone with plastic molding ties to get some sleeves built for M/MA1 series mags to be used in S/SA1 series guns. though the mags will fit without a sleeve its always awkward.
     

  3. hihoslva

    hihoslva New Member

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    Okay. The deal is this:

    Steyr magazines all use one of 3 baseplates. Consider them large, medium, and small (height).

    10 rd. M9 mag uses the large.

    14/15 rd. M9, 10 rd. S40, and 12 rd. M40 use the small.

    10 rd. M40 and 10 rd. S9 mag use the medium.

    Confusing, I know.

    There are NO factory 12 rd S9 magazines. However, one can be MADE by closing the feed lips of an S40 mag to accept and hold 9mm rounds.

    S40 mags have - for some time - been in short supply or not available.

    Here's where it gets tricky.

    To MAKE my own 12 rd. S9 magazine, I bought both a 10rd. M40 and hi-cap M9 magazine. Swapping the baseplates "created" an S40 magazine (M40 mag with the short baseplate = S40 mag). I then closed the feedlips, and made myself a 12 rd. S9 mag.

    I don't know of variations in followers or springs. However my homemade mag has functioned flawlessly - after a little tinkering to get it right. I had to close the feed lips a little more after my first time shooting; rounds were nosing up and missing the chamber. After that tinkering, I've got at least 200 flawless rounds through the magazine with no malfunctions.

    I had a pic showing the mags & baseplates, but can't find it now.

    Edited to add:

    Baseplates on Steyr mags do not hold rounds nor do they determine capacity. The only real purpose is to make the mag sit flush with the butt of the gun. So a 10 round S9 mag has the same body, spring, and follower as a 10rd M9 mag. The extended baseplate of the M9 mag is simply to allow the mag to "fill" the grip of the gun. The same is true for all magazines. So changing baseplates will never change the capacity of the magazine - a'la Glock. The metal mag bodies are different sizes, and this is what determines the capacity.
     
  4. Max

    Max New Member

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    i get it now. :idea: so in actuality, the mag bodies for s9 mags are not tall enough to seat properly if the baseplate is shortened, hence the medium height baseplate. s40 mags are a little taller and can fit in an s9 even with the short baseplate. now if only i could figure out why m9 14rd mags and 15rd are virtually tha same size but have different capacities. :?
     
  5. hihoslva

    hihoslva New Member

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    Know why? Because you can stuff 15 rounds in a 14 round mag.

    I've got a couple of 14 rounders. That's how they were advertsied when I bought them. And they have 14 witness holes on the side to cound rounds. But I can get a 15th round in them without an incredible amount of effort. It's tight, but it fits and functions fine.

    So my guess would be that either it's just how the mags are advertsied (14 vs. 15), or perhaps 1 coil is cut from the spring to make the 15th easier to load. But it's not all that difficult to begin with.
     
  6. bigtaco

    bigtaco Active Member

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    what hihosilva said. if you can't get 15 into your m9 mag, cut a coil off the spring.

    as far as bending feed lips. if you don't have one, get a pair of calipers from harbor freight or enco or one of the cheapy outfits. they're only like $13!!

    measure how far across your m9 feedlips are and then make your s40 feedlips the same widths. bend them by clamping them in a vise so you bend them parellel to each other and you're good to go!! take it easy you only want to close the lips. if you go too far and pull them back apart, that's when trouble starts.
     
  7. uncle_walty

    uncle_walty New Member

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    Cut a coil or use the 10 rounder mag spring which has one less coil. My unmodified 14 rounders were too tight with 15 but have worked great with the 10 rounder springs. The longer spring works fine in the 10 rounders.

    CDNN is now carrying the 15 round M9 mags. They got my hopes up when the latest catalog siad 16 rounds for the M9 mag. But it's a typo since another callout a few pages down indicated 15 rounds. I guess the 16 was more like how shotgun mag capacity is listed.
     
  8. Droptop

    Droptop New Member

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    [quote="hihoslva]To MAKE my own 12 rd. S9 magazine, I bought both a 10rd. M40 and hi-cap M9 magazine. Swapping the baseplates "created" an S40 magazine (M40 mag with the short baseplate = S40 mag). I then closed the feedlips, and made myself a 12 rd. S9 mag.
    [/quote]
    Ok, I have a 10 Round M40 mag. Now where can pick up a high-cap M9 mag? I would very much like to have a flush fitting 12 round S9 mag.
     
  9. AZHTfreak

    AZHTfreak Member

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    Resurrecting an old thread that has some very good information on all the different Steyr mag variations. I bought an S9 about a year ago and love the gun but dislike it's 10rd limit. This thread gave me my solution! Bought a couple S40 10rd mags that should give me 12-13rd 9mm mags with easy mods. The S40 mags can be a tough find. Best price with shipping I've found as of July '16 is $34.48 each + $5.99 USPS at midwestgunworks.com. They have good vendor reviews, very quick shipping and actual pics (!) of each different mag! Now to get out the calipers and practice my feed lip bending technique...
     
  10. Hurry1996

    Hurry1996 Active Member

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    Thanks AZHTfreak. Good information here.
     
  11. AZHTfreak

    AZHTfreak Member

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    Got the S40 mags in the mail. Their feed lips measure 10mm I.D., my 17rd & 10rd 9mm feed lips measure 9mm I.D. Got out the big smooth-jaw needle nose and CAREFULLY bent each lip in 0.5mm. Loaded 'em up with FMJ and hand-cycled 3-4 times with no apparent issues. So far, so good - now to get out to the desert and put 50 rds through each to make sure i've got a couple 12rd S9 mags gtg...!
     
  12. AZHTfreak

    AZHTfreak Member

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    And the modified .40 mags work great! 200 rds downrange between the 2 & 100% trouble free. 12+1 S9-A1!