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Witness Limited Pro minor problems


robport

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I've recently been having some annoying problems with my limited pro in .40SW.

I've been running with low power ammo, around 130 PF using 155 grain moly coated bullets and a 10lb slide spring.

Lately, I've been having problems with the sliding returning very slowly (or not at all) to battery after a reload.

Everything looks normal after a round is fired.

Last night, I thought it was due to the slide release, but I recovered (during a stage) by slapping the back of the slide into battery...which means the slide release had been triggered.

I thought it might be a little problem with the slide to frame fit, but pulled the barrel and there was no resistance whatever, that I could feel.

I don't notice any problems during dry-fire reloads, but I do that in my nice warm house. My shooting, with this pistol, has all been done at 40 degrees F or below on our range

I thought it might just be the cold and the type of lube I'm using (just commercial veggy-oil based RAND CRP), but I was told by an expert with these, that it wouldn't happen.

The things I haven't ruled out yet are problems with the magazine, where resistance of a round being stripped off is causing it and/or the barrel to slide fit...or something I haven't thought of yet.

I suspect it's not the magazine, because I haven't changed the springs yet, so the upward force hasn't suddenly increased.

If I don't have a better way to go, my next step is to just really slather it in oil, especially around the rear of the barrel area.

Any advice?

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Two areas.

1) extractor hook may have a rough edge or burr. Remove it (easy to do - just drive the pin until it pops out), then polish it up.

2) while the extractor is out, polish the breech face.

I had a similar issue and polishing these two areas fixed it. Worth a shot !

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Two areas.

1) extractor hook may have a rough edge or burr. Remove it (easy to do - just drive the pin until it pops out), then polish it up.

2) while the extractor is out, polish the breech face.

I had a similar issue and polishing these two areas fixed it. Worth a shot !

Good advice. Polishing the breech face on a couple of my Tanfos resolved this same issue for me. I now keep the breech face polished on all my Tanfos and CZs.

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Update: I cleaned those up and polished them and the feed ramp (just in case).

I noticed that, as the slide moves forward, the hammer hits the center back part of the slide and it feels like a pretty hard transition.

Of course, I realize I'm doing it by hand and feeling for problems, so I might be making too much of it.

The firing pin retainer, with it's smoother and rounded transition surface, just moves out of the way leaving that sharp slide back edge to move the hammer out of the way.

The retainer is not tight to the retainer groove in the slide and feels like it has a lot of slop in it.

It feels better when cycling by hand and with snap-caps in it. It may be good enough. I can't tell at this point.

I won't get to shoot it until tonight.

Are those firing pin retainers usually loose? If not, is there a standard way to tighten them up?

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I'm a little slow this morning, not following what this means;

I noticed that, as the slide moves forward, the hammer hits the center back part of the slide and it feels like a pretty hard transition.

Of course, I realize I'm doing it by hand and feeling for problems, so I might be making too much of it.

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I wish I had taken pictures.

As the slide is moving forward, the hammer is still in contact with the center of the slide (which reset it as it was going back).

When the back end of the slide re-approaches the hammer, the hammer jumps up until it hits the firing pin retainer, then slides off the retainer into its final position as the slide assembly clears the hammer (the retainer is the last part of the assembly in contact with the hammer).

The retainer has the same profile as the bottom of the slide and looks like it should provide a smooth transition of the hammer. It doesn't because the bottom of the retainer and the bottom of the slide aren't coplanar. The retainer has some "slop" which allows the bottom of it to be higher than the bottom of the slide.

I wish I had the pistol in front of me for a picture or two....

I know 1911's need to have their firing pin retainers polished sometimes. In my limited experience though, I haven't seen a firing pin retainer before that didn't extend to the bottom of the slide or a really loose one.

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Yea, that's how the Tanfo firing pin stops sometimes are. The one on my stock II was the same way. I did still polish the radiused portion to allow the slide to move more smoothly against the hammer face. You may also need to clean up any sharp edges or burrs at the rear (or front) of that rib on the bottom of the slide that runs along the top of the top round in the mag. My mag was digging into the top round case causing the slide not to make it all the way home at times. I cleaned up and very slightly radiused the edge on the front and back and the problems went away.

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It happened Friday night several times, during the classifier...annoying.

Now, I have polished almost everything up (I still want to polish the firing pin safety plunger) and the slide seems to be moving better.

I also did a little bit of work on the roll pin to allow the extractor to move more freely (it was very, very stiff).

...then I had problems with rounds tilting up out of the magazine...so I have now bent the magazine feed lips in a little.

It now works pretty dependably at home by hand. We'll see at the range....

I guess it's a repetitive process...find a problem, fix it, expose another one, fix it...etc.

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It happened Friday night several times, during the classifier...annoying.

Now, I have polished almost everything up (I still want to polish the firing pin safety plunger) and the slide seems to be moving better.

I also did a little bit of work on the roll pin to allow the extractor to move more freely (it was very, very stiff).

...then I had problems with rounds tilting up out of the magazine...so I have now bent the magazine feed lips in a little.

It now works pretty dependably at home by hand. We'll see at the range....

I guess it's a repetitive process...find a problem, fix it, expose another one, fix it...etc.

Had the same problem yesterday. It only happend one time when reloading during slide lock. Looks like the top round has tilted and I can't replicate the problem. I thought I was hitting the mag pouches ( rescomp) when reloading but it does not. Hmmmm annoying.

Edited by bulm540
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I had this exact issue, and for me the fix was learning that the Limited Pro needs "longslide" recoil springs.

A.k.a there is a 2lb offset in spring weight between a Stock2 and a Limited Pro: The same spring that is a 10lb in a Stock 2 is an 8lb in a Limited Pro.

I would recommend a 14lb recoil spring (or 12lb "longslide") in the Limited Pro running minor .40. I bet all your problems disappear.

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I had the same problem with my 9mm Lim Pro, here are some things that I did that eventually corrected the issue.

Found 2 bur's on the rails of my frame, dremeled them off and polished it up nice and smooth.

Put in a "long Slide" wolf 10lb recoil spring

Added more crimp to my bullets

Switched bullets from a BBI 148gr FP to a SNS 147gr RN

Runs like a champ now

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You might also want to make sure there is enough give in your extractor. You mentioned it being stiff. I had used the wolf extractor spring as many people do, but it was way too much and would barely budge, causing some failures to return to battery. I cut a coil or two off and haven't had the problem since.

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Let me see if I understand this... when the trigger was forward (not pinned) you are feeling a significant 'bump' in the slide as it goes forward into battery about the time the hammer is transitioning from the bottom of the slide to the firing pin stop?

If you were to pin the trigger (pull it back like firing and hold it back) - did you feel the same bump in the same place?

In both my tanfos, the FP stop does not extend completely to the bottom of the slide - there is a little bit of a step between the rounded FP stop bottom and the bottom of the slide. There is a noticeable difference in the slide going forward with a trigger pulled to the rear vs. a no finger on the trigger. I had some stoppages on one of my guns as it was going into battery when it was new but those worked out as the gun was broken in a bit.

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http://www.youtube.com/watch?v=2P5Azbwldys

This is the problem. I don't know how much time I'm losing on it, but if it was just .5 seconds, I would have moved up 3 places in our last match...lol

I've polished the extractor, loosened the extractor pivot pin, checked the slide area around the breech face for burrs/roughness and filed what I thought was a rough spot down, polished the firing pin retainer and the hammer where they contact...and readjusted the magazine feed lips. The round chambers smoothly, but the slide is stuck in the furthest aft most position. The gunsmith said it was sprung heavy enough and that he worked on the area where the slide contacted the firing pin retainer.

I was supposed to check it tonight, but I can't go now.

If he didn't fix it, I'll try to catch it in the act and stop. Maybe I can actually see where it is getting hung up.

I have faith in him though. He's quite familiar with these.

Edited by robport
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