1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

Thanks Tuner!!

Discussion in 'Gunsmithing and Repairs' started by 19112XS, Jun 12, 2004.

  1. 19112XS

    19112XS Well-Known Member

    Thanks Tuner! Periodically I fire out the carry ammo in my very reliable 5" Springfield LW (ramped barrel, 18.5 recoil spring) to replace it with fresh. The last time the Cor-Bons did nosedives in 2 CMC 10x and 2 CMC 8x mags. This was fairly upsetting, but when the same mags refused to feed BALL, I was indeed unhappy but not panicked. Because of your very informative postings, the issues with all 4 mags were resolved with a call to Wolff GunSprings and 2 three-packs of their +5% mag springs. The 5" feeds any and all now and once again provides comfort and pleasure. The only unresolved issue is with a Springfield Champion I tried out today. Cor-Bons and ball both feed out of the SA mags and CMC 8x's, but still nosedive in the freshly sprung 10x's with this pistol. I don't see this as a major problem since the smaller mags function well. Could these nosedives be a result of the shorter recycle timing associated with the Champion? Thanks again for sharing your knowledge. You saved me $$ and frustration.
  2. Delmar

    Delmar Well-Known Member


    I have a similar issue with my Colt Officers model. My government models eat anything I feed them within reason, but the officer likes its food with a max overall length of 1.260, and 1.250 a whole lot better. New mags or not-doesn't seem to matter.
  3. 1911Tuner

    1911Tuner Moderator Emeritus


    Howdy 'Leven 2 times,

    Those nose dives...Top round from slidelock or at random through
    the magazine?

    When the magazine is topped off...Is the top round up against the feed lips? If you push down on the round...will it return to position or does it
    stay in a nose-down attitude?

    The 10-round magazines have a little disadvantage to overcome...The spring has to be strong enough to time the rise of the last round or two in the tube without bein' so strong that it's hard to load it to capacity...and there just ain't a lotta leeway. When it starts to get tired, it doesn't have enough tension on the front end to keep the top round nose-forward, and nose-dives result. It reaches a line of departure and the friction of the round trying to slide past the one under it overcomes the spring's loading on the front. It's a balancing act that'll get thrown outta balance when
    the spring gets a little wear on it. Sometimes...due to tolerances and variations in the loading of a new spring...it can't provide correct tension
    on both ends. Nosediving the top round, or Rideover feeds on the last round. Flip a coin.

    Hope this helps...

  4. 19112XS

    19112XS Well-Known Member

    Hi Tuner.

    Of course your advice helps. It helps a lot.

    Before respringing both 10x's and both 8x's, with the 5" (Champion N/A at that time,) the nosedives always occurred with the first round (Cor-Bon) out of the magazine during a normal firing cycle and sometimes the second round. After respringing all mags, with the 5", all are functioning as they should with any ammunition.

    After respringing, using the 10x mags in the Champion, nosedives occur with the first 4 or 5 rounds (also Cor-Bons) out of the mag during the normal firing cycle. I honestly don't remember if the same occurred with ball, but will retest soon. The Cor-Bons fed normally from the resprung 8x mags into the Champion.

    The nosedives never were random-always when the mag was at its fullest, never as it approached empty.

    When the resprung 10x mags are topped off, the top round is fully against the feed lips. After pushing the nose of the top round down into the mag, it will return to approximately 90% of its previous position two-thirds of the time and to the fully upright position the remainder.

    Thanks again for giving us all the benefit of your experience.

    Delmar-I have a little experience with a 3" Kimber Ultra Carry. It fed any and all amazingly well and was an accurate little booger. Overall length and nose shape of the ammunition does play an important part in proper feeding. I'll look for appropriate kind as needed. Thanks for your advice.
  5. 1911Tuner

    1911Tuner Moderator Emeritus


    Howdy 19112XS,

    Sounds like maybe your follower angle is too close to 90 degrees. Take the follower out of the mag and trace it on paper for a reference. Clamp
    the back leg in a vise as close to the bend as you can. (I assume it's a
    Devel split-type)

    The problem with the extra capacity followers is that the rear leg is necessarily shorter than the standard 7-round followers, and they're not as stable in the tubes...even under a load. They tend to rock forward,
    and when the follower nose-dives, so do the rounds. The added friction
    of the new spring puts more drag on the round under it, and makes it more likely to happen.

    Wedge a flat screwdriver under the lower leaf and pry upward on it a little, to raise the front up a bit...about the thickness of the sheet metal is
    all you want at this point...and try the magazine. If the nose diving is reduced, open the TOP leaf up a little...again, about the thickness of the
    sheet metal.

    You can also get a little more upward tension on the front by putting a light upward kink in the top coil of the spring about 2/3rds of the way from the
    turn to the front, right under the spot that it contacts the follower. Do this after tweaking the follower angle...IF the tweak seems to make it feed better.

    Keep us posted on how it works...Sometimes it does...Sometimes not.


  6. 19112XS

    19112XS Well-Known Member

    Hi Tuner.

    Finally got a chance to work with the follower and spring. You're right, the follower angle was a bit too close to 90 degrees. I adjusted that and put the kink in the spring of two 10x's as you suggested. The feeding condition seems to be unchanged. The 5" again does fine (after a bit of tweaking) and the Champion still will not feed the first Cor-Bon from the magazine. I will work with this more, but for the moment I'm short on time and Cor-Bons. Feeding the 5" is meat, feeding the Champion is gravy. Thank you again (and again and again) for the benefit of your knowledge and experience.
  7. 1911Tuner

    1911Tuner Moderator Emeritus

    10X Still no Feed

    Well...Sometimes those extra-cap single-stacks just don't work as
    advertised in all guns. Might be a feed ramp angle on the Champ is a little
    out of spec...Might be the OAL on the Cor-Bons aren't compatible with that
    particular gun...Might even be the reduced slide mass in the Champion.
    Hard to figure this one without the gun on the bench. If Wolff makes
    springs for that mag...about all you can do is try that. Still a crapshoot
    whenever you stray very far from design parameters...and with the short
    pistol AND the long mags, you've doubled the chances of a burp.

    How does it do with the magazines that were designed for it?

    How does it do if you short load the 10 rounders by one round?
  8. 19112XS

    19112XS Well-Known Member

    Hi Tuner.

    The Champion feeds the Cor-Bons from the factory Springfield 7x mags. These have a substantial front leg to prevent the rocking forward you referred to. I think you're right about a bad combination of factors. I'll not waste resources worring about the Champion with the 10x'ers, at least at this time. If it'll feed ashtrays reliably with something, and the 10x's will work reliably in the 5", I'm set.

    I don't know how the Champion will feed if the 10x's are shorted by one, but will let you know.

    Thanks a bunch.
  9. 19112XS

    19112XS Well-Known Member

    Hi Tuner.

    The Champion will feed CorBons with it's own 7x mags only. Shorting the 10x's does not help.

    Related PM sent.

    Thanks for your patience.

Share This Page