M&P thumb latch mismatch

guitar1580 · Apr 14, 2012

I posted this on the collector's side last night, not thinking about the fact that those guys are probably at gun shows for the weekend. I hope it's ok to double post it here, where it may get more views, and possibly solved.

"I just picked up a nice old .38 M&P with a ship date of Dec 1950. The thumb latch was hanging up, and seemed to be a little cocked, as if it were maybe tilted a little when the screw was last tightened.

When I took it off in order to lube & re-attach, I noticed that it is the old style like my guns from the teens have - a full double pinch hourglass around the screw, with the undercut relief around the latch edge - the earliest of this family of latches I think (correct me if I'm wrong).

I'm fairly certain that style is too old for my 1950 gun, but I'm not sure which of the several versions it should have. I'm thinking the 2nd or 3rd style, as in, full hourglass with no undercut around the latch edge, or single pinch hourglass. I know some older leftover ones got used up on some post war guns, but I wouldn't expect up until 1950. I figured one of you guys will know which one would have most likely been used at the mid century point, or maybe have a 1950 gun you can look at.

I did get the latch functioning properly with some Kroil, and a re installation of the latch, but I would still like to get the proper piece for this old beauty. I would greatly appreciate if anyone can pinpoint which thumb piece I should be searching for, and would appreciate even more if someone can dig an old blue one out of the parts drawer to sell to me

. The M&P has moderate finish wear, so it doesn't need to be a mint one."

Thanks, Josh P

FRAN357 · Apr 14, 2012

filedown a new one.That is what i did.

guitar1580 · Apr 14, 2012

Edit: pics

I'm having my doubts now as to whether or not this is even a S&W thumb latch. Notice how it flares out to a bit of a "point" at the red arrows, where the latches on all of my other guns are more rounded in that area, as in bottom photo (from a 1917). Also notice the rough machining at the yellow arrows. The latch even feels different.

JP

glowe · Apr 14, 2012

I would agree that the thumb latch is not S&W, since the workmanship looks sub-par. Looking at all my pre-1950s 38 hand ejectors, they all look like your 1917 size and shape. I think some delicate grinding, followed by polishing and bluing will give you a good looking thumb latch.

Hondo44 · Apr 15, 2012

I believe your thumblatch is an S&W and correct for your gun. I have latches exactly like yours with course marks. Although it is a pre war style, as you said, they are found on early post war guns both before and after the second style was used.

Early post war guns were rushed out the door with satin finishes and sometimes small polishing flaws to quell the pent up demand for their products.

The flared edges are indicative of the hand shaping of the edge surfaces by different parts finishers and in fact your 1917 latch shape varies from the norm as well, being a little too rounded to my eye. It's also ill fitting since it has left a rub mark on the frame from incorrect contact which is not normal.

Reshape to your preference or look for another either pre war style or 2nd style (single pinch) to your liking; either would be historically correct for a 1950 era gun.

guitar1580 · Apr 15, 2012

Thanks Jim, that's good info. You helped me figure out the flat latch variations a while ago, and sent me some great info. I did figure out that the latch was replaced on this gun, so I'll likely try to find a better looking one.

As I recall, isn't there another variation between the single and double pinch, which would be double pinch but without the undercut edge? Do you know if that one was used on the M&P too around 1950, or should I look for the single pinch style? I saw a few on ebay for $10 to 15, but they're the 70s style, with no hourglass, so I'm not sure how hard it will be to find a slightly older one.

Here are pics of a my 1905 3rd and 4th change, both full hourglass and undercut edge. They are both more consistent with the more rounded shape of the 1917 that I posted above.

Josh P

Hondo44 · Apr 15, 2012

Hi Josh,

Yes, this thumbpiece, double hourglass with no relief cuts would be the 1st original post war, that could be found on M&Ps of your vintage:

The next style, the single pinch would be correct as well since as we know they weren't used in order:

Your 1905 pics prove me wrong on those early pre war latches, they do tend to be more rounded than following the war. Thanks for your post.

I checked my stash but do not have any of the style you need. N frame latches are the same size.

guitar1580 · Apr 15, 2012

Thanks for the info and pics, Jim. Is it ok to use your pics to show which style I need if I place a want ad?

JP

Hondo44 · Apr 15, 2012

guitar1580 said:
Thanks for the info and pics, Jim. Is it ok to use your pics to show which style I need if I place a want ad?

JP

Yes of course most pics I use aren't mine anyway.

guitar1580 · Apr 22, 2012

update on the odd latch, and pics

I snapped a few pics of these latch variations we were talking about. One reason that odd one doesn't work properly is that it's either worn or ground to an angle on its base where it should be flat - but I still think it's non S&W. Luckily it didn't booger up the slot in the frame. It's pictured here with a newer one from a 1968 gun (top), which has the different base setup & making them non interchangeable.

The lower pics show the two variations on the gun. I'm glad I ran onto the base variation, because that's what I'll have to check for when I look for the replacement.

Josh P

Hondo44 · Apr 22, 2012

The latch in the 1st picture is probably original to your 1950 vintage K frame. It's a pre war leftover used on many early post war guns like yours.

As you can see the bolt that the latch attaches to has the slightest step around the screw on one side. It's normally more pronounced like the bolt in the lower gun shown. But that's not an issue. If the base on the latch is ground on an angle as you describe, that would make it mount on an angle and drag on the frame.

I would correct the original latch by removing the angle and re-install. If it still drags on the frame I would replace the latch with the same type. Or an easier solution would be to add a little solder to the base of the latch, square it off and it will shim the latch to raise the latch up slightly so it clears the frame.

guitar1580 · Apr 22, 2012

The previous owner did replace the latch, so it's definitely not the original. I noticed the first time that I used it, that it felt odd. It digs into your thumb somehow, where it's knurled ... and that part seems to be not dished as deep, making the edges feel different on your thumb, and the flared "points" by the red arrows in my original post.

I asked a local gunsmith and he said there are some similar ones that get used as replacements. I think he may have mentioned Rossi, but not sure.

JP

Engine49guy · Apr 24, 2012

Just went through my M&P's,
If its any help my early post war K22's and M&P's up until 1949 still have the Pre war style hourglass shape latch,

A December 1950 Terrier is my oldest S&W with a newer style NON hourglass shape latch and my December 1951 Chiefs special has the first style flat latch ,
An early 1950 gun might go either way.

On a side note S&W did not waste material and I doubt they just tossed the old latches when they changed to the new style.

One story suggests that when new parts were delivered they were dumped into bins on top of the old stock,
As the supply got low workers could hit a "Vein" of old stock .
I do not know the validity of the story but it might help explain why sometimes guns with serial numbers a bit higher than the known transition are found with older style latches.

guitar1580 · Apr 24, 2012

Thanks for the info., Engine. It is very useful. I'm just going to try to find an authentic used SW thumb latch. As long as it has the split back base where it attaches to the gun, it seems that any of the early styles could have been used on a gun like mine from 1950.

JP

Hondo44 · Apr 24, 2012

Engine49guy said:
On a side note S&W did not waste material and I doubt they just tossed the old latches when they changed to the new style.

One story suggests that when new parts were delivered they were dumped into bins on top of the old stock,
As the supply got low workers could hit a "Vein" of old stock .
I do not know the validity of the story but it might help explain why sometimes guns with serial numbers a bit higher than the known transition are found with older style latches.

You're correct I believe this story has wide acceptance.

There are two different double hourglass latches; pre war and 1st post war new style as sown below. Did you notice if you have both?

Here's the pre war thumbpiece, left overs also used on very early post war guns: the 'double hourglass' or double 'pinch' around screw hole with undercut checkered pad;

2nd style, and first new post war thumbpiece, still has the double 'pinch' but without relief cut under checkered pad.

guitar1580 · Apr 24, 2012

Jim do you know which style was the first to go to the solid base instead of split?

JP

Hondo44 · Apr 25, 2012

guitar1580 said:
Jim do you know which style was the first to go to the solid base instead of split?
JP

In a word, no. But if I had to guess, gun-to-my-head, only the 4th style standard thumbpiece was not split and I'd say the transition was in the 1960s.

And I say that based on a survey of my collection (with exceptions being the rule w/Smiths):

I & J frames:
All pre flat latch are split.
All flat latches are split.
All post flat latch are non-split (began post 1966)

K frames:
I have no FL K frames but most likely they are split based on the I & J frames above.
All my '50s K frames are split including a 19-1 from 1961.
All non-pinned barreled Ks I have (earliest is 1980) are non-split.

N frames (never used flat latches):
All my '50s models are split. I have no N frames newer than 1956.

Based on the fact that you're convinced the latch was changed on your M&P, and absent the actual reason for the change, I have two theories:
1.) It was not a FL and was lost and replaced. In that case it was probably a 4th style standard thumbpiece because I don't know that the K frame latches had the same evolution of 2nd and 3rd styles like the I frames.
2.) If it was a FL, many flat latches were changed by owners due to their dislike, non-traditional looks or both. Especially if it was a 1st style FL which would be likely considering the vintage of your gun. Of course the bolt it's attached to required replacement w/the FL type.

Just my common sense theories and worth no more than what it cost. We need to hear from more early '50s K frames owners. Some believe only the 1st type FL was used on Ks and/or only on Airweights.

M&P thumb latch mismatch

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