Old School Witness 9x21 Open Mag Capacity

[Glk21C]

I found that the factory CZ75 25 round 9mm mags work/fit in this used Witness open gun I purchased a few months ago. The first time I used the mags however I found that when the mag is filled with 25 rounds, after about 10 shots the next round will jamb. The bullet acts as though it is feeding too high? as it is sitting at about the 1-2 o'clock position at the feed ramp of the barrel. Once I drop the mag, release that round, and insert the mag back in, the rest of them feed fine.

Your thoughts? thanks

[BrianH]

Try seating your bullets just a little bit deeper.

[sinnsyk]

Wow. Helluwa mount you got on that gun... Other than that, the gun looks identical to the ones I was shooting pre-'95 before I switched to 38 super. Still the same great grip and feel as the new guns today! Also see you've got a WCPI hammer on it with probably the matching EGW sear - great setup! In not too long we'll have a very similar hammer/sear combination available again.

The small frame Tanfoglio mags measure 1.250" x 0.850". I don't know the measurements of the CZ mags or how they intermix. I agree with Brian, try seating the bullets deeper. Now depending on how deep they already are. Shooting Round Nose bullets, try 1.15". Also, old shitty brass can cause trouble. Try a box of factory Round Nose ammo and see how they work. If they give you trouble then the magspring/follower may need to be tuned.

If you need new chrome 9mm mags w/ pads, I've got a special stash of 18 rounders. I've also got 140mm pads that'll give you 20 + 1.

[Glk21C]

The person I had bought it from was loading 9x21, 7.9 grains of W540 with a 135 grain truncated cone jacketed bullet, Winchester Small Rifle Primer, 1.160" OAL, 175pf. He had sent me some of those bullets and they fed fine in the 19 round mags he sent me with the gun.

The load I settled on was 9x21, 6.7 grains n350, 125 lead rn, same primers, 1.152, 166pf.

The brass I have in now 2-3 times fired Winchester and Starline 9x21. All appears to be in good shape. I have a couple thousand brand new Starline brass too, was just waiting to use it until I got the load where I wanted it.

What do you think? and thanks for the replies so far. Will any of Grams springs and followers work in the small frame mags?

Edited March 6, 2007 by Glk21C

[sinnsyk]

The Grams kit is for the large frames only. I don't really know the CZ mags, but if the mag itself is functional in a CZ maybe it'll work for Tanfoglio as well, I don't know. One thing to check is how high the mag sits in the frame. Since the gun is pre 2004, you have an older style mag catch. Check to see if the mag rattles up/down in the frame. It's easier to feel this when you've taken the upper off. I carry mag catch'es for large frames, but don't have any new style for the small frame. What you can do [if the rattling is a case] is to take the mag catch out and weld up and recut the little lip that holds the mag, forcing the mag to sit higher in frame.

For a fact, this was a huge improvement for the 40 S&W feeding in the large frame. All guns sold after 2004 have this mag catch, older guns don't. I never really had a problem with 9mm or 38 super in this respect, but this mag catch is now present in these calibers as well and it can only mean one thing: the next cartridge in the magazine gets to sit higher in the frame and closer to the feed ramp. What this means is that the chance of nose dives are reduced.

For 40 S&W, that typically shoots a jacketed hollow point or a Flat Nose bullet, less blunt surface has to "challenge" the feedramp as the slide tries to feed the next round into chamber.

Edited March 6, 2007 by sinnsyk