1911 Magazine sensitivity

the45er · August 5, 2020, 09:35 AM

I own 10 1911's - no "upper end" pistols, just Colt, Springfield Armory, Kimber, Remington, Magnum Research and Taurus. No customization of any of them. Obviously I've accumulated a fair number of magazines over the years.

In shooting my SA Champion and working on loads yesterday and this morning, I noticed that many of these mags would not retain the slide on the last shot. At first I thought it was the loads, but then I just started checking by pulling the slide back on an empty mag/chamber. Even some of my Colt mags would not retain the slide.

Now, since this "retention failure" was not happening with several of my other 1911's tested, one might assume that it is the pistol, not the mags. But if the pistol itself is out of adjustment, then why do some work and some don't?

Lastly, other than be careful that I only use "working mags" with this particular pistol, is there anything I can do to the mags that won't work in this gun to correct the problem?

Sharkbite · August 5, 2020, 10:17 AM

You dont mention what brand magazines you are using. Original Colt mags have a tab on the follower that can be adjusted to put the proper pressure on the slide stop. Other brands (Wilson) have the “tab” built into the molded follower and cant be adjusted.

Some additional info on your mags might help

the45er · August 5, 2020, 10:46 AM

Here is a pic that represents most of my 1911 magazine collection. I'm pretty sure that the stainless mag with no inscription is one of the two that came with the Springfield Armory Champion I'm having issues with.

I don't see any "tabs" that Sharkbite mentioned, but I'm not sure I know what I'm looking for either.

Incidentally, the only two mags of these five that failed to lock the slide back were the two Colt magazines. I just don't get it!

Sharkbite · August 5, 2020, 11:41 AM

Yep. Got it.

The Colt Mags, when viewed from the side where the mag follower interacts with the slide stop, has a part of the follower that appears to be a “tab”. It is actually just a shelf made out of part of the follower. That is the part that interacts with the slide stop, pushing up on the interior portion of the slide stop when the mag is empty.

Its not uncommon to need to adjust (bend) this tab up or down to ensure proper function.

If you take the slide off the frame and re-insert the slide stop in the frame, the insert an empty mag, you can clearly see the interaction of the parts

**44 AMP** · August 5, 2020, 12:04 PM

Look at the magazine from the back, so you are looking down at the follower.

The original follower design has a portion of the front left (as you are looking at it) that is "stepped down" from the rest of the follower. viewed from the side it resembles a reversed letter "L".

This part of the follower contacts the "lump" of the slide stop lever that protrudes into the magazine well, and lift it up, engaging the slide stop to hold the slide open when the magazine is empty.

Original design followers have this step or shelf and it is able to be bent slightly, if needed, to "adjust" it to put the proper pressure on the slide stop.

That's what Sharkbite is calling a "tab". If your followers are something other than the original (GI spec) design, you're on your own.

It's unlikely the gun is at fault. Most likely cause (and yes with several mags from different makers) is either the follower has become slightly bent OR the magazine spring has weakened, so the follower is not being lifted up high enough for positive function of the slide stop.

Either, or both together is entirely possible and more likely than the gun itself being the problem. IF some magazines work correctly and some don't, the problem is not the gun, it is the magazine(s) that don't work right.

the45er · August 5, 2020, 01:04 PM

You are increasing my understanding of the variation in 1911 mags exponentially! Thank you.

Attached is a photo graph of the sides of the Colt magazine (left) and a different (Meg Gar) magazine (right). The Colt held the slide back on:

another 5" Springfield Armory, both Colts, a Remington and a Magnum Research 1911. Only would not hold the slide back on a SA Champion and a Taurus 1911 I have.

Notice the difference in the angle formed by the two top pieces of the magazine follower (the "duck bill" if you will). All of the Colt mags have a noticeably wider angle than the Meg Gar and other mags I have (see pic). Notice that the bottom plate of the duckbill closer to the lip of the mag on the body (due to this larger angle I suppose). The bottom lip of the Colt mags also have a downward protruding (90 degrees) additional piece of metal as part of the follower that the other mags don't have.

I'm guessing that the slide stop cannot interact properly with the Colt mag as there is a lot less "room" for it than in the other mags?

I can't bend anything in these followers and the base plates don't seem to be removable on the Colt mags (at least a fair amount of force didn't do it!)

Should I buy another slide stop from SA or is there something else to try.

CDW4ME · August 5, 2020, 01:32 PM

1911's can be magazine picky, but I've had 100% success with Trip/Cobra 7 round flush fit 45 acp mags.

bamaranger · August 5, 2020, 02:40 PM

The 1911 pistol is notoriously infamous for being picky about magazines. The simple answer is find the ones that work in your gun, and relegate the ones that don't to other guns or for practice. Marking each mag permanently with a number or letter will identify the mag and help you establish its home and personality.

My immediate thought about a repairing a mag that is not locking the slide back on empty is to install a new, same make mag spring. Modern springs are tough, but can fatigue none the less. The interaction between the slide lock lever, plunger and plunger spring tension can effect how much "push" the lever lug needs from the magazine follower to effect lock. The easiest thing to replace effecting function would be a new mag spring. The fact that the mag in its existing condition WILL lock certain pistols, and the Champion WILL lock with other mags, makes me think the locking function of the Champion may need a bit more of a nudge to work from the mag in question.

Mix and match magazines can lead to tolerance stack and failure as you've noted.

Sharkbite · August 5, 2020, 02:40 PM

Colt mags do not have removable base plates, but can be disassembled.

Depress the follower with a rod most of the way down. Insert a punch into the witness holes low enough to catch the compressed spring but not the follower. Turn mag upside down anf the follower can be removed, leaving the spring captive.

jimku · August 6, 2020, 03:55 PM

Very informative. I only have one 1911 and run nothing but Wilson Combat mags in it ... zero problems.

JDBerg · August 6, 2020, 04:27 PM

Quote:

Originally Posted by jimku:

Very informative. I only have one 1911 and run nothing but Wilson Combat mags in it ... zero problems.

#47D’s for the .45 ACP’s, ETM’s for the 9mm here, likewise zero problems

**Aguila Blanca** · August 6, 2020, 04:49 PM

Quote:

Attached is a photo graph of the sides of the Colt magazine (left) and a different (Meg Gar) magazine (right). The Colt held the slide back on:

another 5" Springfield Armory, both Colts, a Remington and a Magnum Research 1911. Only would not hold the slide back on a SA Champion and a Taurus 1911 I have.

The two problem pistols may need a different slide stop.

dahermit · August 6, 2020, 06:23 PM

Quote:

In shooting my SA Champion and working on loads yesterday and this morning, I noticed that many of these mags would not retain the slide on the last shot.

If the mags work in the other 1911's, logically it is the SA Champion that needs adjusting of the slide lock.

Crankylove · August 6, 2020, 07:59 PM

Quote:

I only have one 1911 and run nothing but Wilson Combat mags in it ... zero problems.

I’ve only got 1 1911 as well. Have used 5-6 different brands of magazines over the last 10-12 years, none were as reliable as the Wilson’s. Got rid of the rest, now all I run is the 47D’s.

the45er · August 7, 2020, 07:41 AM

Quote:

Originally Posted by dahermit

If the mags work in the other 1911's, logically it is the SA Champion that needs adjusting of the slide lock.

For whatever reason, out of 23 1911 mags I own, the only ones that will not hold the slide back on the Springfield Armory Champion are the Colt magazines. However, since the other SA 1911 I own (a 1911 A-1 stainless) works fine with these Colt mags, I tend to agree with this post.

TunnelRat · August 7, 2020, 09:05 AM

Quote:

Originally Posted by Crankylove

I’ve only got 1 1911 as well. Have used 5-6 different brands of magazines over the last 10-12 years, none were as reliable as the Wilson’s. Got rid of the rest, now all I run is the 47D’s.

Me three I guess. I’ve had good luck with the Wilson 47Ds. Really flawless luck I guess. I have also used some 7 rd GI pattern magazines by Springfield Armory without any issues.

Sent from my iPhone using Tapatalk

August 5, 2020, 09:35 AM	#1
the45er Senior Member Join Date: July 10, 2008 Location: The mini-hill country of Texas Posts: 254	1911 Magazine sensitivity I own 10 1911's - no "upper end" pistols, just Colt, Springfield Armory, Kimber, Remington, Magnum Research and Taurus. No customization of any of them. Obviously I've accumulated a fair number of magazines over the years. In shooting my SA Champion and working on loads yesterday and this morning, I noticed that many of these mags would not retain the slide on the last shot. At first I thought it was the loads, but then I just started checking by pulling the slide back on an empty mag/chamber. Even some of my Colt mags would not retain the slide. Now, since this "retention failure" was not happening with several of my other 1911's tested, one might assume that it is the pistol, not the mags. But if the pistol itself is out of adjustment, then why do some work and some don't? Lastly, other than be careful that I only use "working mags" with this particular pistol, is there anything I can do to the mags that won't work in this gun to correct the problem?

August 5, 2020, 12:04 PM	#5
44 AMP Staff Join Date: March 11, 2006 Location: Upper US Posts: 28,832	Look at the magazine from the back, so you are looking down at the follower. The original follower design has a portion of the front left (as you are looking at it) that is "stepped down" from the rest of the follower. viewed from the side it resembles a reversed letter "L". This part of the follower contacts the "lump" of the slide stop lever that protrudes into the magazine well, and lift it up, engaging the slide stop to hold the slide open when the magazine is empty. Original design followers have this step or shelf and it is able to be bent slightly, if needed, to "adjust" it to put the proper pressure on the slide stop. That's what Sharkbite is calling a "tab". If your followers are something other than the original (GI spec) design, you're on your own. It's unlikely the gun is at fault. Most likely cause (and yes with several mags from different makers) is either the follower has become slightly bent OR the magazine spring has weakened, so the follower is not being lifted up high enough for positive function of the slide stop. Either, or both together is entirely possible and more likely than the gun itself being the problem. IF some magazines work correctly and some don't, the problem is not the gun, it is the magazine(s) that don't work right. __________________ All else being equal (and it almost never is) bigger bullets tend to work better.

August 5, 2020, 01:32 PM	#7
CDW4ME Senior Member Join Date: March 18, 2009 Posts: 1,321	1911's can be magazine picky, but I've had 100% success with Trip/Cobra 7 round flush fit 45 acp mags. __________________ Strive to carry the handgun you would want anywhere, everywhere; forget that good area bullcrap. "Wouldn't want to / Nobody volunteer to" get shot by _____ is not indicative of quickly incapacitating.

August 5, 2020, 02:40 PM	#8
bamaranger Senior Member Join Date: October 9, 2009 Location: North Alabama Posts: 8,308	mags The 1911 pistol is notoriously infamous for being picky about magazines. The simple answer is find the ones that work in your gun, and relegate the ones that don't to other guns or for practice. Marking each mag permanently with a number or letter will identify the mag and help you establish its home and personality. My immediate thought about a repairing a mag that is not locking the slide back on empty is to install a new, same make mag spring. Modern springs are tough, but can fatigue none the less. The interaction between the slide lock lever, plunger and plunger spring tension can effect how much "push" the lever lug needs from the magazine follower to effect lock. The easiest thing to replace effecting function would be a new mag spring. The fact that the mag in its existing condition WILL lock certain pistols, and the Champion WILL lock with other mags, makes me think the locking function of the Champion may need a bit more of a nudge to work from the mag in question. Mix and match magazines can lead to tolerance stack and failure as you've noted.

August 5, 2020, 10:17 AM	#2
Sharkbite Senior Member Join Date: November 4, 2013 Location: Western slope of Colorado Posts: 3,679	You dont mention what brand magazines you are using. Original Colt mags have a tab on the follower that can be adjusted to put the proper pressure on the slide stop. Other brands (Wilson) have the “tab” built into the molded follower and cant be adjusted. Some additional info on your mags might help

August 5, 2020, 11:41 AM	#4
Sharkbite Senior Member Join Date: November 4, 2013 Location: Western slope of Colorado Posts: 3,679	Yep. Got it. The Colt Mags, when viewed from the side where the mag follower interacts with the slide stop, has a part of the follower that appears to be a “tab”. It is actually just a shelf made out of part of the follower. That is the part that interacts with the slide stop, pushing up on the interior portion of the slide stop when the mag is empty. Its not uncommon to need to adjust (bend) this tab up or down to ensure proper function. If you take the slide off the frame and re-insert the slide stop in the frame, the insert an empty mag, you can clearly see the interaction of the parts

August 6, 2020, 03:55 PM	#10
jimku Junior member Join Date: January 2, 2017 Posts: 291	Very informative. I only have one 1911 and run nothing but Wilson Combat mags in it ... zero problems.