Premature Slide Stop

[DonNikmare]

FYI for you guys...

In the e-mail about the bushing I asked Mike if there is something I could do to alliviate the premature slide stop problem.  In case you have not read in my posts in the gen area, I had about 8 to 10 premature slide stops in about 250 rounds.
Here is what Mike wrote back...

Quote:As for the premature slide stop problem, I recomend removing the slide stop spring (#2) and giving the rear working leg a downward bend, at the knee (1/2" from the end).
It is held in place by a small pin (#4) with a groove
in the middle. It is this spring that is designed to keep the slide stop down and out of the way, until the mag follower over powers it. Good luck and good shooting.

I guess I'll have to get the manual out n see what he's talking about cause I ain't got a clue where this spring is. It was nice of him to include the numbers.

Any of you done this before?

Nik

[dleong]

Nik,

Yup, I had to do that on my 97B and 40S&W 75B to alleviate a premature slide lock activation problem when the pistols were new.

It is a very straightforward and simple procedure:

1. Field-strip your 97B. Remove the wood grips to prevent them from being nicked or damaged. Lay the frame flat on its left side.

2. The Slide Stop Spring Pin (#4) is located in the hole just forward of the Slide Stop opening. Using a 1/16" pin punch and a hammer, drift the SSSP out of the hole towards the inside of the slide. Invert the slide--the Slide Stop Spring (#3, not #2 as indicated in Mike's reply) should fall out.

3. Bend the SSS as described by Mike.

4. Insert the SSS back into its channel. Using a thin, flat-bladed screwdriver, press the straight portion of the SSS down while inserting the SSSP back into its hole from the outside of the slide. The SSSP should "snap" into place when its groove catches the SSS.

5. Insert the Slide Stop into the slide and verify that there is additional tension keeping the Slide Stop down. If not, you might have to remove the SSS again and put a more aggressive bend in it.

6. Remove the Slide Stop and reassemble the pistol.

Hope that helps!

DL

[DonNikmare]

Dleong,
Thanks for the detailed instructions!  I'll print them out n follow along one of these upcoming evenings after the kids are off to bed.
Nik

[DonNikmare]

Did this today.  Was not as hard as I thought it would be except for getting the pin to snap back in. Man that was hard.

I had to get the curved part of the spring out of its slot in the frame well n drift it down in it in order to be able to knock the pin back into place. Then I used a small screw driver to lift it back in its slot.

I used a short piece of a toothpick with the sharp ends broken off instead of a 1/16" pin punch and it worked well.  I was afraid of the punch scraping or scratching the poly on the pin.
dleong thanks again for the instructions - they helped a lot.

Nik

[Lazarus]

Suggestion:
Always refer to the basics first, before assuming that custom gunsmithing is required.

The two most common reasons for the slide to lock back before the magazine is empty are:
1). Improper grip position, or limp-wristing.  Thumbs are hitting the slide lock lever during firing.  
2). A bad magazine - will result in slide lock at next-to-the-last-round.
Also note that if you are using a rest, and there is weight on bottom of the magazine that forces it up into the gun, this will aggravate problem #2.  The same thing goes if the old style "cup and saucer" grip is being used.

-Lazarus

[Walt-Sherrill]

You're right to say that you should make sure that you're not hitting the slide, etc.  But when the gun does it consistently on the next to last round, for example, its unlikely to be a GRIP problem.    And that has been the case with most of the folks who have described their problems, here.

A bad mag spring CAN CAUSE a premature slide lock -- as several of us have noted.   (A weak spring can let the rounds move forward as the slide slams home, and they they're in position to nudge the slide stop.)  

Trying the "problem" mag in another gun will often let you determine whether its mag (spring) or gun (slide stop), but not everyone has that luxury.  I did, and found that the mags in question caused problems in every gun.

It can also be a defective slide stop -- but that generally causes problems from the first, and not just with the last round or two in the mag. It doesn't become a problem after months of shooting without the problem.

[DonNikmare]

The premature slide stops were so many in the shooting session in which they occurred that I had plenty of time to make sure it was not my grip/thumbs knocking it up.

Yes, it would fall under custom gunsmithing but I did what Mike suggested mainly because it was the most economic fix, if it turns out to be a fix - my next time at the range should tell.

I do think the mag springs being weak is the main cause as Walt n others suggested when I first bought up the issue in a different thread.  I did clean the mags n stretched the springs a bit n the bullets were a little harder to push in but I'm thinking that won't last long.

If the problem continues, changing the mag springs will be my next step.  

I will also be looking to see if the bullets tips bumping the slide stop up could be what's going on.  It seems it would be hard to tell what caused what.  Almost every time I had a premature slide stop n looked into the extractor port the left side of the bullet was touching the bottom of the slide stop.
So, did the bullet push the slide stop up or did it just look that way because the slide stop was already up n the bullet just bumped into it?

My rambling has brought me back to the likely cause of weak mag springs as it would seem there is nothing to push the bullet half way out up into the slide stop, except for a weak mag spring allowing it to come out, if the slide is locked in by the slide stop.  I better stop before I confuse myself anymore  

Lazarus and Walt thank you both for the tips.

Nik