1911 variant issue

[Dan in MI]

I recently bought a Colt Commander 9mm clone. The brand has good reviews and so far excellent customer service. I really like the gun.

From day one it will not lock open after the last round. Works fine by hand but not when firing.

WW white box, Blazer brass 115 and 124, my reloads all act the same and all work fine in all my other 9mm's.
Five different magazines (two brands) -- same
I measured the slide stop and saw a minor difference from a spare I had - -no change
Before I tested the extra slide stop I had I called and they were sending me a replacement -- no change with either one
Next test was swapping out the recoil spring with Colt 9mm -- nope
Replaced the ejector with a long version (matches Colt factory) -- no luck
Tried the recoil spring from my Colt 45 -- 40-50% success rate
Bought two brands of expensive defense ammo - factory spring -- no luck, 45 spring close to 100% functionality (90-95?)

A good friend of mine is a well known smith, while he hasn't looked at it, he is stumped. He knows my knowledge level and trusts my reports. He has also talked with another nationally known smith in passing about it. He doesn't have any suggestions either.

I also swapped what I could from the new gun to my Colt, sadly it's not 100% clone so I can't swap everything in the upper. It will take the complete Colt upper but I can't swap to the Colt frame for an A/B test. Same issue with the complete Colt upper.

I called the company again. The recoil spring is supposed to be 16# it is 20#. The Colt 9mm is 16/17, the 45 is 15/16. The are sending me a new spring to try.

I found a review that said he had the same issue. He tried a 10 round magazine and it worked.
I am currently waiting on the new spring while also considering ordering Wolff recoil spring assortment and extra strength magazine springs.
I have two more brands of magazines to try.
Also going to hot rod some ammo.

I am considering burning up 500 or more rounds just to see if it needs a break in. The gun is pretty tight.

I know I can send it back but it is a pain and I like to tinker and as long as the company is being supportive I'm willing to play.

Anybody have any ideas?

 

[contender]

I've used a lot of 10 round 1911 magazines in competition. I'd give a Chip McCormick or a Wilson 10 round mag & see what happens. They just WORK!

 

[Dan in MI]

I have both in .45. One of the brand magazines I tried us Ed Brown. They seem to be very good. He has a deal where you send in any mag and for $10 you get one of theirs. I had some real trash mags and gave it a shot.

 

[DGW1949]

Make sure your gun has the Commander-length barrel bushing. An incorrect (Government-length) bushing will allow the gun to fire and (usually) feed but will not allow the slide to fully retract.

DGW

 

[Wvfarrier]

Tripp mags are my go to for 9mm 1911s.

 

[Sam Summey]

Is there any interference of the barrel "hood" and the slide breach face when the barrel and the slide is in lock up? It should be a slight gap between the hood and the slide breach face. Try assembling the Commander without the recoil spring and operate the slide by hand. Look for binding in the slide travel. (Do NOT attempt to shoot the Commander without the recoil springe present.)

 

[Dan in MI]

I will look, but I think swapping the complete Colt upper would have made a difference there.

Digging around yesterday I found a few recoil spring charts. They almost all have 9mm Commander length using a 9-13# spring. Might need to order a set of Wolff's.

 

[OMCHamlin]

I went through this with a pair of 9mm Springfield Armory 1911 Range Officers. Both gave last round lock open issues, I’m going to tell you I cured both of them with either an Ed Brown or a Wilson Combat Bulletproof slide stop specific to 9mm.

 

[Dan in MI]

I have springs (factory and Wolff) and CMC mags on the way. I will look into the slide stop if I don't find a cure. I have swapped slide stops, but they were factory.

 

[Dan in MI]

Ok after more testing and swapping of parts and mags still no joy. There were a few flashes of luck, but no real consistent fix. So I burned up a bunch of ammo to see if it needed some break in and with the hope if that wasn't it the gun would have some wear points to indicate something.

Apparently that worked. Took it apart at home and started looking at the wear and possible issue points. I'm pretty sure I have a link that is too long. There is battering on the barrel lugs where they fit into the slide. Gonna have to send it back. I could fix it, but I'll let them. Maybe they will slick it up a bit too.

 

[Dan in MI]

So, it went back and returned very quickly. Roughly a week round trip.

I was apprehensive about the fix when I read the notes. Pretty much duplicated what I had done. Replace slide stop, replace recoil spring and polish the feed ramp. They polished it too! it's a mirror.

I took it out and burned up a bunch of various ammo, in various mags, and it works like a champ now. I took the spring out and measured it. 13# versus 20. I noticed a big change in where the brass lands. Old spring right at, even on, my right foot. With the new spring about 5 feet over my right shoulder. Both were in small groups not all over.

Is there any interference of the barrel "hood" and the slide breach face when the barrel and the slide is in lock up? It should be a slight gap between the hood and the slide breach face. Try assembling the Commander without the recoil spring and operate the slide by hand. Look for binding in the slide travel. (Do NOT attempt to shoot the Commander without the recoil spring present.)

I did check that prior to returning it. There are battering signs on the recoil lugs. I can catch my fingernail on them. I mentioned that to the mfr , but apparently they didn't look at the marks as they were still there. I filed them off and polished up the area last night. We'll see if I even notice a difference when shooting. I could feel a difference racking slowly by hand, so I know it can't hurt

 

[XUSNORDIE]

 

[Dan in MI]

Yeah, do we a clone bot running around?

 

[XUSNORDIE]

Yeah, do we a clone bot running around?

They should call themselves "mockingbird"......weird post though......AI joining forums now and mimicking posts?

 

[Blackhawk Convertable]

Tripp mags are my go to for 9mm 1911s.

Tripp mags for my 45acp's

 

[Dan in MI]

The locking lugs before I cleaned them up. Look at the forward edge on top.

 

[Dan in MI]

Well, I lied. Second outing was still way better but about 80/85% proper function. In more digging I found a nugget that I truly believe is the issue. Apparently it is not spoken about much, but 9mm/38 Super get a unique slide stop. While it is always a separate part to order, I never saw a reason why until now. I found only two instances in a LOT of digging that told the dimensions of the slide stop lug. Every slide stop I have tried was .197" but one. It was about .200" which was the one that ran better. In finding this nugget I started looking at the follower and stop engagement. The amount of engagement varied from mag to mag and, of course, the more engagement the better they worked. I finally found a #3 length slide stop and plan on testing as soon as I can. I can tell you that on the worst mag I can clearly see MUCH more engagement. For your reference the "golden nugget" of info.

The second reference of dimensions.