1911 not locking back after last round

[*chris*]

Recently picked up a used S&W PC 1911 and it is not reliably locking back after the last round with any of my magazines including the factory mags. The same ammo and magazines work perfectly in my Ruger 1911 commander so I don't think it is the ammo. How do I begin to troubleshoot this issue? I cleaned and lubed the gun, so it isn't dirty.

Chris

 

[qqac]

Check the slide stop lever. See figure 1 in this link. http://www.brazoscustom.com/magart/0505.htm

 

[icyclefar]

Will it lock back solidly if you insert an empty mag and rack the slide?

 

[chrbla2000]

maybe a stupid question, but one of your thumbs isn't riding the slide release is it?

-chris

 

[*chris*]

Will it lock back solidly if you insert an empty mag and rack the slide?

I'll check again tonight, but I think it always locks back with an empty magazine and racking the slide, almost seems like there is too much slop in the mag catch.

chrbla2000, I am left handed so I don't have any appendages near the slide stop lever. My Ruger 1911 operates perfectly.

Chris

 

[mark056]

Swap out your Ruger slide stop with your S&W and see if that makes a difference. There should be parts interoperability at that level. Your pistol is not going to blow up or anything. If it works okay with the Ruger slide stop, you will have identified the problem.

 

[M60]

Swap out your Ruger slide stop with your S&W and see if that makes a difference. There should be parts interoperability at that level. Your pistol is not going to blow up or anything. If it works okay with the Ruger slide stop, you will have identified the problem.

What he said above. Perhaps the former owner swapped out the original slide release and the replacement slide release hasn't been fitted to your 1911 which could prevent it from getting high enough up into the slide to hold it to the rear. An aftermarket slide release often has to be fitted to function correctly. At least your Ruger slide release has been fitted to the Ruger slide, so it may work in the other slide.

 

[Gammon]

Failure to lock on the last shot is almost always due to short stroking. Weak ammo or strong recoil spring, maybe both. Try different ammo or weaker recoil spring.

PS In reference to an improperly fitted slide stop; I have been shooting and tinkering with 1911s for over 30 years and never had to adjust or fit one.

 

[*chris*]

I looked at the gun last night and it locks back every time when racking it by hand. I looked at the slide stop and it doesn't appear to be modified in any way. I will have to wait for the seller to tell me if the recoil spring is stock or not. I assume it is. I am using ammo that I reloaded that is almost full power with a 230gn rn bullet. That ammo functions perfectly in 6 or so other 1911s that I have used it in ranging from Colts, AO and Rugers. I found some factory ammo which I will test the gun with before I go any further.

The slide on the S&W gun has absolutely no slop, so maybe it is just tighter and drags more than the less expensive 1911s that I have owned in the past.

I am using Mil-Com Tw25b grease on the slide and my gun was cold, I wonder if that has something to do with it.

 

[DW357]

I ran into this issue with my Coonan 357 mag 1911 last weekend at the range. I shot through 200 hot reloads and I'd say 3-5 times it didn't lock back after the last round. It locks back easily with a empty mag inserted though. I'm wondering if the factory 22lb recoil spring is too light? It throws my brass 30+ ft away. Is it possible that these near max reloads cause the slide to rack back so fast and then bounce/slam back forward? I bought a 24, 26 and 28 lb Wolff spring to test out.

Ill have to take a look at the slide stop lever later tonight after reading other suggestions.

Edit: after reading some Coonan threads on the 1911 forums, seems like it's either a slide stop issue or a mag follower issue which is totally possible and makes sense.

 

[Greg Derr]

Gammon had good advice, I would add that the presence of a "shok buff" or recoil buffer can have ill effects on the slide stop function. sometimes too light a recoil spring can allow the slide to move so fast that the mag follower has little time to catch up and engage the slide stop.

 

[M60]

Failure to lock on the last shot is almost always due to short stroking. Weak ammo or strong recoil spring, maybe both. Try different ammo or weaker recoil spring.

PS In reference to an improperly fitted slide stop; I have been shooting and tinkering with 1911s for over 30 years and never had to adjust or fit one.

Years ago there was a gunsmith on the south shore named Don Hamilton. He had to hand fit a new slide release for me on a Colt that was resulting in exactly what the OP's slide is doing. Don showed me the problem prior to fitting and said that when he finished fitting it, the slide would function correctly. Don was right. After fitting, the slide and release functioned flawlessly together. The new slide release had to be filed to fit into the slide correctly, in order to hold it back on the last shot. I'm thinking that Greg Derr would concur with Don's remedy since Greg told me that Don was his mentor.

 

[DW357]

Gammon had good advice, I would add that the presence of a "shok buff" or recoil buffer can have ill effects on the slide stop function. sometimes too light a recoil spring can allow the slide to move so fast that the mag follower has little time to catch up and engage the slide stop.

Okay that's what I was wondering. I think that's what is happening with my Coonan. Those loads are pretty hot and the fact that brass gets tossed 30-40 feet away tells me the spring is indeed too light.

 

[M1911]

Swap out your Ruger slide stop with your S&W and see if that makes a difference. There should be parts interoperability at that level. Your pistol is not going to blow up or anything. If it works okay with the Ruger slide stop, you will have identified the problem.

This.

Swap in the other slide stop. If it works, then you know what the problem is.

 

[*chris*]

Gammon had good advice, I would add that the presence of a "shok buff" or recoil buffer can have ill effects on the slide stop function. sometimes too light a recoil spring can allow the slide to move so fast that the mag follower has little time to catch up and engage the slide stop.

Interesting, I never thought that too light a spring could cause this.

No recoil buffer in this gun.

My Bubba racking of this gun versus my Ruger 1911 "feel" the same, but I am not sure I could feel the difference in spring weights.

Thanks for the advice, seems like I have a few things to try.

Chris

 

[Supermoto]

A light recoil spring will actually give the slide stop move time to lock the slide because the slide will stop longer when it is all the way back

Watch around 3:30 on

 

[DW357]

Tried a 28 lb spring in my Coonan today and it kept the brass down to about 20 feet away or so. Before it was 30-40 feet away lol. But I still had issues with the slide not locking back on the last round. I might shoot Coonan an email and see what they recommend.

Do they make recoil springs heavier than 28 pounds?

 

[*chris*]

So I checked my recipe book and I am loading 6 gn of Unique under a 230gn jacketed bullet which is the max load for the bullet. Reloading guide says 800 FPS.

Would I be better off with 231, Titegroup, or HS-6 in this cartridge?

Chris

 

[Gammon]

A 230 gr bullet at 800 fps scores a 180 power factor in USPSA terms which should be more than enough to operate a 45 with a stock (16 lb) spring. Before you go any further you should chrono your ammo and verify that your recoil spring is a stock 16 lbs.

 

[spt_1955]

I ran into this issue with my Coonan 357 mag 1911 last weekend at the range. I shot through 200 hot reloads and I'd say 3-5 times it didn't lock back after the last round. It locks back easily with a empty mag inserted though. I'm wondering if the factory 22lb recoil spring is too light? It throws my brass 30+ ft away. Is it possible that these near max reloads cause the slide to rack back so fast and then bounce/slam back forward? I bought a 24, 26 and 28 lb Wolff spring to test out.

Ill have to take a look at the slide stop lever later tonight after reading other suggestions.

Edit: after reading some Coonan threads on the 1911 forums, seems like it's either a slide stop issue or a mag follower issue which is totally possible and makes sense.

If it locks every time when racked manually it is probably not a mag follower issue.

 

[DW357]

If it locks every time when racked manually it is probably not a mag follower issue.

Ohh aright. Well I emailed Coonan and they're going to get back to me soon.

 

[Gammon]

Tried a 28 lb spring in my Coonan today and it kept the brass down to about 20 feet away or so. Before it was 30-40 feet away lol. But I still had issues with the slide not locking back on the last round. I might shoot Coonan an email and see what they recommend.

Do they make recoil springs heavier than 28 pounds?

I noticed some Coonan springs on Wolff's web site. The stock spring was rated at 22 lbs. Maybe you should give them a call, they are very helpful.

 

[drgrant]

So I checked my recipe book and I am loading 6 gn of Unique under a 230gn jacketed bullet which is the max load for the bullet. Reloading guide says 800 FPS.

Would I be better off with 231, Titegroup, or HS-6 in this cartridge?

Chris

Unique is better than at least the first 2. WAY better. I used 6.2-6.3 grs and got into low-mid 800s with it. I bet 6 grs is slow. You might have made yourself a nice fluff load. Smiths are oversprung from the factory too, or at least they seem that way.

-Mike

 

[DW357]

I noticed some Coonan springs on Wolff's web site. The stock spring was rated at 22 lbs. Maybe you should give them a call, they are very helpful.

I emailed Wolff and they said they use to make a 30lb spring but people couldn't rack the slide so they stopped making them lol. Also Coonan got back to me and had this to say:

Often when the slide is not locking back on the last round it is because of a lubrication issue or an ammunition issue. Ultimately the slide lock function depends on pressure and resistance. If there is too much resistance and not enough pressure the slide will not travel far enough for the slide lock to engage. Try using the green ten pound recoil spring with your current ammunition to see if that makes a difference. If it does you may need to try different ammunition. Also use the included FP-10 to lubricate the pistol. Be sure to apply a liberal amount of oil to the area of the barrel visible when the pistol is in battery.

 

[*chris*]

Unique is better than at least the first 2. WAY better. I used 6.2-6.3 grs and got into low-mid 800s with it. I bet 6 grs is slow. You might have made yourself a nice fluff load. Smiths are oversprung from the factory too, or at least they seem that way.

-Mike

Interesting, maybe I should increase to 6.2 then. You think .2 - .3 would make that much of a difference?

Chris

 

[Gammon]

Unique is better than at least the first 2. WAY better. I used 6.2-6.3 grs and got into low-mid 800s with it. I bet 6 grs is slow. You might have made yourself a nice fluff load. Smiths are oversprung from the factory too, or at least they seem that way.

-Mike

I disagree. WW 231 is an excellent powder for 45 ACP loads. I have been using it for over 30 years with great results.

 

[drgrant]

I disagree. WW 231 is an excellent powder for 45 ACP loads. I have been using it for over 30 years with great results.

It's a pain in the ass to get and doesn't scale for hot, but safe loads. It does suck less in .45 than it does in other calibers though. I used to use a 5.7gr 230 ball load for pins.... but eventually power pistol and unique won out. Win WST is better for fluff loads if thats what one is aiming for.

 

[Gammon]

It's a pain in the ass to get and doesn't scale for hot, but safe loads. It does suck less in .45 than it does in other calibers though. I used to use a 5.7gr 230 ball load for pins.... but eventually power pistol and unique won out. Win WST is better for fluff loads if thats what one is aiming for.

WW 231 is a pain to get because it is so popular. I have been using it for all of my non magnum loads with great results. 231 is the first powder I used and, after over 30 years and several hundred thousand rounds of experimentation, still my favorite.

 

[highlander]

I'm guessing that you know HP 38 is the same as 231. Picked up an 8 lb keg at Glenn's Reloading awhile back for $160 plus tax.

 

[DW357]

Shot 100 rounds on Saturday and the slide locked back only 3 out of the 15 mag reloads. Emailed Coonan again and also told them the slide was releasing on its own when inserting a loaded mag. Lastly, I noticed some burrs in the notch where the slide stop lever sits in. They replied this morning that they're sending me a return label to ship it back to them to fix the issue. Hopefully this can be fixed easily.

Is this normal wear? Or maybe normal to a 1911 in 357 mag? lol. You can see the burr sticking out from the notch in the slide and the metal on the lever looks slightly deformed?

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