Slide Stop & Magazine Woes...

[boo radley]

So I've been shooting an STI for the last two weeks, and really like it -- it's quite a change from the Glock. The magazines, however, are another issue.

I have 6 40S&W magazines -- 4 I bought new from Dawson, and two I bought used. I also bought two Grams spring/follower kits from Chuck.

The slide locks open after the last round with every magazine. Worse, with the Grams followers, it locks back with one left in the mag (just found this out today). Called the gunsmith last week, and he said, 'yeah, with some followers, you have to trim them a bit with a dremel..."

My understanding was the slide-stop was trimmed to disallow slide-lock on an empty gun. But seeing that with *none* of my followers, this works, I'm wondering if this is the case. Attached is a picture -- has this slide-stop already been trimmed? I don't want to go to work on it, if so. OTOH, if not....It also appears to be an MIM part. Out of curiosity, is the slide-stop MIM on STI's?

I read the article on Brazos' page, but it's hard to know WTF to cut and trim, and dremel.

My slide-stop has bevels everywhere on the notched part. And why do the Grams followers/springs cause the slide to lock open with ONE round left?

With Area 6 in a couple days, I'm inclined to ditch the Grams guts, not touch anything for now, and just live with the slide-lock issue. But down the road, I need to get this fixed...Buy another slide-stop? Grind followers? Grind the existing slide-stop? Thx!

Edited April 29, 2007 by boo radley

[Sestock]

I have a detent in all of my slide stops for the plugger spring tip. The detent keeps the slide stop from engaging. I still can mannually lock back the slide.

[John Kane]

+1 on the detent. Nothing else worked for me consistently.

[boo radley]

Just add a dimple there, where the shiny spot is? Hmm.. might order a back-up SS, then give that a try. Thx!

[G-ManBart]

From the looks of it your slide stop hasn't been trimmed a lot...maybe some, but not a lot.

The Grams followers will engage the slide stop with one round left because the bottom of the follower is closer to the top of the mags than with a stock STI follower...put a magazine with each next to one another and it's easy to see.

The fix is actually really easy (but the detent is still a good idea). Take the slide off the gun, put the slide stop back in the frame, make sure the slide stop is depressed all the way and then insert a magazine with a dummy round in it. When you insert that mag you'll see the slide stop pop up. You'll see where the slide stop is contacting the follower. Trim that area of the follower down until the slide stop doesn't pop up above the frame level when you insert the magazine with one round left and that will leave enough for the slide to lock back on an empty mag (you'll have to do each mag this way).

If you don't want the slide to lock back ever (except when you manually engage it) you can trim either each mag follower so that it won't push up the slide stop up when you insert an empty mag, or you can trim that part of the slide stop where it touches the follower and be done with it.

I did all my followers so that the gun will lock back when empty because I really don't want to hear the dreaded click if I run it empty...a reload at that point is a lot slower than a reload from lockback. I will say that I put a couple thousand rounds through the gun after that and have never had it lock back except when empty, so it's worked so far.

[CDRODA396]

Hey Boo,

I think all new STI owners go through this. It's painful, especially considering what you paid for the gun and the magazines, followers, bases, etc., but once you get them right, they run and run....

If the mags you have are not tuned, then the distance between feed lips will also affect how high the follower can go before the lips stop it. If they're not tuned, there are several threads on here where someone has posted the link to the proper dimensions and it can be found on STI's webpage, then you need to spend a little time with a inside/outside caliper and some small pliers with taped up (or protected) "pinchers" and get them in specs.

If they are tuned, or once you "tune" them, then you have to decide to lock back or not.

Having spent 20 yrs in the service I like my guns to lock back...so I took my dremel to the range, fired three rounds, the slide locked back with one round, dremeled and repeated until I got them all running right. It suprised me how much of the ledge I had to take off.

If you dont want it to lock back, Brazos' article shows the slide stop modifications, and I believe he still recommends dremeling a little on the follower.

G Man Bart lays that out a pretty good technique for that.

Good Luck and I hope you get them running before Saturday!

Edited April 30, 2007 by CDRODA396

[hitman]

You can also try Dawson +1 followers.

[lucas]

I just went through this.Only dif was i want the slide to lock back but not with a round left in the mag.The fix which was suggested and can work for your other problem aswell was to shape the grams follower ledge about 45 degree from the top to the bottom.Being in a hurry and doing it at the range i would scrape the ledge using my bench made knife , load 3 rounds ,and test it untill i got it right.It was a bummer.With my knife i would scrape from the rear of the ledge to the front kinda like peeling a apple ,scraping towards your thumb but with the knife edge facing down and not towards you.I had to do it to every mother one of them.After the 4th one i said the hell with it for now, and put in the ISMI 11 coil spring with STI followers in the rest of them which work just find and called it a day.Never had these problems with grams before now i read its the norm.

[boo radley]

All is well. Called Caylor and the slide-stop was stock (explained he put in a stock one so the customer could modify as desired for lock vs. non-lock).

Out came the Dremel®.

I ended up doing all three of the steps on the Brazos website: grinding down the slide-stop, adding a detent, and -- on the Grams followers -- grind them a bit, too. Now nothing is locking back.

Boy - you don't need much of a detent -- think I got a bit carried away and now it take a bit of effort TO engage the stop...

Now I just have to learn how to shoot this gun, and change the setting from "MIKE".