Feeding problems off midcaps

Discussion in 'General Airsoft Discussion' started by S1kkguy, Nov 18, 2012.

  1. S1kkguy

    S1kkguy New Member

    489
    2
    London
    Hey guys. Basically while experimenting with my mags today I came across an annoying problem. For some reason, my classic army ak midcap magazines won't feed .25s at a mere 20rps. It feeds .2s fine but will skip a BB every other trigger pull on auto with .25s. My CYMA hicap feeds fine regardless of rps or weight so finding it pretty annoying.

    So what I'm asking is, anyone know if there is something I can do to make them feed? I'm pretty good with GB internals but never really needed to open up a mag before.
     
  2. McGee

    McGee New Member

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    San Francisco
    Problems with feeding:

    1. Magazine can't fit right - it's not high enough for the hop-up chamber tube to press the BB catch back far enough, it too far off-center, etc.

    2. Magazine tube is too wide - BB get jammed side-by-side in the magazine and don't get pushed up by the spring

    3. Magazine spring is too weak.

    4. Too much friction is the magazine.


    Your issue might be a weak spring, if lighter weight BB can get pushed up. I bet you that's not the case - emptying the magazine allows the spring to regain some 'spring', so taking all .25's out and replacing it with new BB is probably what made the difference. Also, the magazine might have been cleared of dust when you did this. Also, the BB may not be the same diameter...

    But, MID-CAPS get weak springs. That's why I stopped using them. I only use standards - 68 rounds, etc. I have had these full for weeks with zero loss of spring energy. STANDARD MAGs are the most durable.

    Don't put silicone in the mag. Lots of people suggest this, but they're wrong. Maybe a temporary fix, but think about this - silicone oil on Bio BB. Silicone oil and the dust it collects, including BB dust. Silicone oil globs on your BB as it flies through the air. Silicone oil residue on our hop-up. This is not theory, this is experience talking.

    Good non-winding magazines allow you to split them apart and clean them. I used to do this every couple games. I'd stretch the spring out while I was at it.

    Cheap non-winding mags are disposable, basically. $5 for one of those is not a bargain in my opinion. Especially with a KWA - I pretty much have terrible luck getting MAG magazines (110 round, etc.) to feed in my KWA.

    I love Marui Std., and Classic Army Std. I've used King Arms Std. (metal) but they are clearly lower quality (and half the price).

    Consider this - if your mag does not feed, you are essentially 'out of ammo'.
    Pay more for magazines, people.
     
    Last edited: Nov 19, 2012

  3. S1kkguy

    S1kkguy New Member

    489
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    London
    I'm sure it's due to a weak spring. So is stretching it the best way to increase tension then?
     
  4. Lefse

    Lefse Well-Known Member Supporting Member

    6,228
    1,840
    You can also search up the bb follower mod. You basically use a file or knife to reshape the follower so that the bb's won't sit side by side in the magazine. By the way, my KA AK mags feed .25's at 38rps with no issues, doesn't even need a tappet delayer.
     
    Last edited: Nov 19, 2012
  5. S1kkguy

    S1kkguy New Member

    489
    2
    London
    Cheers mate will just open up the mags today and start trying things out. Didn't think I'd have a problem with the mags considering they were classic army and I paid bloody £68 ($108) for a box of 6 plus shipping...B0llox man...
     
  6. FSTK

    FSTK Member

    877
    0
    I've had this problem with STAR midcaps too. The bb-follower would get stuck in the plastic molding on the sides of the well. I would have to whack the mag a few times to get it to feed again before the problem reappears during fire. It was truly annoying. I know the pain well. This is why I don't run an all-midcap rig anymore.

    If you have a file, check to see if the circular seams (or imperfections) along the wall/bb track is free of imperfections. I also learned that it's not good to remove the bb spacer if there exists one. If the spring tension isn't high enough: it leads to jams because the restoring force isn't strong enough to overcome the friction inside the bb well.

    Good luck and do report back if you find success. :)
     
  7. McGee

    McGee New Member

    464
    1
    San Francisco
    My 4 newest Marui mags failed to feed when I first used them. Shocking...

    However, they are fine now. I'm sure the 'finishing' on the follower and/or magazine sides was poorer than normal, and use has 'filed' the imperfections down.
     
  8. Ghostwalker Tech

    Ghostwalker Tech Active Member

    109
    31
    Raleigh
    I realize this is a Necropost, but I feel it is needed to comment here for others having the same issues to this day.
    I too agree with not putting silicone oil in the mags. However, if you get some spray silicone and spray it on the channels, let the excess run off, the carrier will evaporate and leave a film behind, from there lightly wipe out the excess it should be fine and not impact the performance of the hopup since the bbs will have minimal surface contact in the channels.
    Second, do not stretch your springs. Instead to increase the efficiency of the spring put a block or possibly 2 bbs at the end of the channel under your spring end. This increases the energy stored in the spring without ruining its structural integrity, ie stretching the spring. Whether or not this is a temp fix remains to be seen. But my guess is that the mags will wear out before the spring does using this trick. All mag springs are not created equal.
    Next, check your mags for front to back wobble and side to side. I have been finding recently, particularly with AK mags, that the tolerance of mag wells from brand to brand have a great variance(E&L and LCT specifically, I have no experience with other brands, but my guess is the you will find the same among other brands). If you have issues with back to front wobble on AK's you may need to add some epoxy or other substance to build up the lip ends to fit snugly in the mag catch and or front lip, or you may need to file some off. The mags should not be tight, but have a snug fit and feel solidly locked in. For E&L AK's, Im not sure if this was by design or accident, but E&Ls have a plastic plate that is held in with 2 nuts screwed on to the bottom of the hopup bolts. You can use these bolts to adjust the back and forth wobble by adjusting them up or down until you find that sweet spot. I would place washers underneath these nuts for support or threadlock them once you have found that sweet spot. For side to side wobble I am not a fan of modifying the gun to fit but rather modding the mags to fit the gun. I disassemble the mag and take some thin plastic card stock(old yogurt land rewards cards work great!!) for shimming and place it on the inside of the mag at the top between the mechanism housing and the outer shell, reassemble the mag and test for side to side snugness. If you use your mags in more than 1 gun then you may have to find a happy medium between the 2 through testing. A little wobble is ok, but no more than .02-.03mm if you can get it there. Its time consuming and arduous, but in the end your mags should not wobble and this can contribute to mag feeding issues because they are not aligning with the hopup feed tube and bbs get hung up there. I had just the opposite with M4 mags. I actually had to file down the back of the mags to get them to fit properly. Once I did this they now feed perfectly every single time.
     
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