S&W magazine problem

[edrice]

I bought a S&W model 411 back in the early 90s, which later became the model 410 after the Clinton fiasco that reduced max rounds to 10. The 411 came with 11-round magazines and there were a few other minor differences.

When I bought the gun I also got extra mags so I had a total of four. I never fired this weapon much till a few years ago and I then discovered that one of the magazines seems to cause the magazine safety to engage. I can fire one or two rounds, or else can just pull the trigger with the safety off on an empty gun, and after one or two pulls, the trigger just goes back and forth and won't activate the hammer anymore.

This only happens with this one magazine and the rest are fine. I called S&W a couple years back and they never heard of that and sent me a new follower which I installed but it didn't fix anything. I had compared and measured this magazine to the other three and cannot find any differences. I also checked the height while it was locked in place in the magazine well.

I just recently took it to a gunsmith, he did the same things I did plus exchanged various parts and couldn't come up with a solution. But he said it was definitely the magazine.

I live in California and we're still under the 10-round magazine thing but this one is grandfathered in because it's pre-ban and I hate to lose an 11-rounder even it is only one more round. It's the principle of the thing.

Has anyone ever had an experience like this or have any insight as to what could be causing this?

Thanks!

Ed

 

[rcmodel]

The S&W magazine safety actually has nothing at all to do with the follower.
Afterall, it must work with a fully loaded magazine, and the follower is down in the bottom of the magazine then!

The way it works on the 39 series is, the magazine body itself pushes the ejector/disconnect lever up when it is inserted fully into the gun. That allows the trigger linkage to engage.
A spring loaded plunger in the slide (under the rear sight) pushes it down without a magazine in the gun.

Take the slide off, hold the ejector down as if the slide was on the gun, and watch a magazine that works, as you seat it.

Notice the left rear of the mag pushes the ejector / mag disconnect lever up just as it locks in place.

Now try the mag that doesn't work.

Whatever the difference in mag bodies is, that right there is your problem.

Try bending the bad mag slightly until it pushes the ejector up like the good mag, and it should work.

rcmodel

 

[edrice]

Thanks, rcmodel!

Yeah, I knew that about the follower but did it anyway just to humor S&W. When I had it at the gunsmith's he did a little bending on the magazine and it didn't seem to change anything, but when I get home this evening, I'm going to try your methodology and see what I can see.

Thanks for the input! I'll report back.

Ed

 

[rcmodel]

The only other thing it could be is, the lock notch is cut too high in your bad mag, and it's not locking in where it should.

Hold the mag up in the gun as far as possible and see what happens.

If it works then, about your only option would be to have the lock notch TIG welded & recut lower.

Or, since you live in Kalifooornia, maybe S&W would / could supply you with a new mag or mag body on an exchange basis?

rcmodel

 

[edrice]

Now, there's an excellent idea! I hadn't thought about trying an exchange. I'll follow up on that.

Yeah, pressing the magazine as high as it would go was one of the first things I tried.

Ed