Modified my Steyr M40-A1 magazine

Discussion in 'Maintenance / Tweaks / Technical Difficulties / So' started by timfife, Jun 11, 2010.

  1. timfife

    timfife New Member

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    I got a wild hair and decided to see if I could cut 2 "loops" from the Steyr magazine spring and reinstall to add another round. It worked. I was wondering if anyone else has done this and has had problems or success? Any foreseeable or possible problems I might encounter? Problems with pressure? Problems with feeding? Everything seems to work fine. I was told to NOT cycle live ammo through the magazine so I have not tried and don't have any snap caps.

    Thanks

    www.timfife.blogspot.com
     
  2. Syntax360

    Syntax360 Moderator

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    I wouldn't go near a project like that - the factory Steyr mag springs seem pretty dicey in stock configuration... But if you did it, and it works, good onya. Possible problems to watch for will be, of course, feeding issues or perhaps a failure to lock after the last round of the magazine is shot.
     

  3. timfife

    timfife New Member

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    I did insert the mag and the slide held back. I'll run some rounds through it this weekend. Rumor is Steyr is making a +2 for the mags. Can anyone confirm this?
     
  4. Syntax360

    Syntax360 Moderator

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    That would be cool, but there hasn't been much reason to believe Steyr-Mannlicher is paying attention to the pistol line at present. The 17 round magazine was the last pistol-related accessory they released, and the floorplate and body design differ from the traditional M(A1) magazine design. If an extension was released, I really wonder whether it would be compatible with the magazines that 99.9% of us have on hand...

    More likely, some people saw the release of the 17 round magazine and assumed it was just a different floorplate that could be transferred to the 15 round magazines. It would then seem like a no-brainer for Steyr to offer a +2 extension, but as I said, it's a new design altogether.

    We shall see...
     
  5. timfife

    timfife New Member

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    So as far as anyone knows, the M40A-1 has only 10-12 round mags available? I see CDNN is listing them for 19.99-23.99 now (10-12). The 17 round mag I assume is for the 9mm?
     
  6. bigtaco

    bigtaco Active Member

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    correct.

    and the big difference between the 15 rounders and the 17 rounders is that:

    the bottom of the 15 round magazine body bends IN.

    the bottom of the 17 rounder bends OUT.


    ergo, adding extensions of any type to the 15 rounder, any of the 10 rounders and the 12 round 40 mags is a no go. the magazine spring will not be able to pass over the "wings" bent into the mag body.

    when steyr was designing the pistol 15 rounds was what they built around and extensions were of no concern.

    i'm so enthused to see the 17 rounders have the wings bent out. it allows the use of the +2 extensions that they're using to give us 17 rounds but also allows us to use longer extensions.

    not that there's anyone with an injection molding machine dying to design one. i'm wondering if an existing extension would snap onto the bottom of the 17 round steyr mag. we'd just need to find someone that had M+P mag extensions and a 17 round steyr mag.

    how 'bout it steyrclub? anyone got both of those items to give it a whirl?



    as to cutting coils on mag springs... just a bad idea in general. the biggest issue to me isn't last round hold open, i rarely shoot to slide lock under any conditions. i'd be much more concerned about feeding the last 2 rounds. that's where i'd focus my testing. load 2, shoot, repeat. if that ran 50 times i'd try full mags and want to see it feed at least 10 full mags without malf before i'd begin to feel cozy with it.
     
    Last edited: Jun 11, 2010
  7. timfife

    timfife New Member

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    Thanks bigtaco, I'll do it this weekend and post my findings. The gunsmith I work with at the shop and I may to some brain storming and tinkering. Not much to work on tomorrow, maybe a shotgun and some bolt action rifles I think. Learning how to do the real tree and mossy oak dip also. Harder than it would seem...
     
  8. Soverign

    Soverign Premium Member

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    Search the forum for the threads about using S&W or BHP mags that can be modified to fit.
    An S&W M&P mag will give your 40 a 14 round count...
     
  9. ETH77

    ETH77 Premium Member

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    Hold on BT, I can't believe I didn't notice the bend out flaps before. That's what it would take to put an Arredondo extension on the mag. Try the M&P extension, you can probably get +4 or +5 rounds if it fits. Don't worry about the weird slant, or get an XD extension. The mag specs should be the same. For $17, it might be worth a try.
     
  10. bigtaco

    bigtaco Active Member

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    knowing that ANY existing extension would slam right onto a 17 round steyr mag would be GREAT... for us 9mm competitors. there's no "plus" mag for the 40... YET.

    how 'bout YOU give it a shot? you've got extensions so all you'd need is the mag to try. i completely agree that it should work. but "shoulds" haven't been going my way lately.


    if i actually whale together a magwell i'd LOVE to stick thumb rests on the A1 and shoot limited.
     
  11. timfife

    timfife New Member

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    Well I ran about 6 mags through and no problems. I was expecting the last two to misfeed but it worked great. Still a lot of spring left. I also ran 2 rounds through 12 x's and worked fine. I think I'll get some XD extensions and try that also. + 4 sounds better.
     
  12. bigtaco

    bigtaco Active Member

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    13+1 running fine.

    now just watch that the spring doesn't wear out pretty quickly.

    do your 40 mags have tabs that bend out? do the XD mags have tabs that bend in?
     
  13. gondive

    gondive New Member

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    I see it has been some time since you modified your mags, any new update on how it all worked out?
    thanks,
     
  14. 5hift

    5hift New Member

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    any updates on this? a few pointers would be greatly appreciated. Thanks in advance.
     
  15. strawman1988

    strawman1988 New Member

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    Major reason is bought the l9- a1 was mag capacity would have bought l40 if I could get +2 extension very interested in this please update!