are 639 mags compatible with a 539?

marc1984

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I picked up a 639 and a 539 (nickel plated). The 639 came with 3 mags. The 639 mags look the same as the 539 mag. I can insert the 539 mag in the 639, but none of the 639 mags want to insert into the 539, without a good amount of force.

Are mags for a 639 compatible with a 539?

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Thanks
 
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That's what I figure, but the force required makes me concerned that I will damage something in the 539. The mags insert smooth in their respective guns, and the 539 mag fits smooth in the 639.
 
Images of the 539 and 639
These are the links to my images that are not displaying. The links are wrapped in the img tags. There is a second set of links below this box with the img tags. They are just not visible for some reason.
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https://imgur.com/dqXoHvq
https://imgur.com/7VtpTwh
https://imgur.com/7ZZVHfC
https://imgur.com/kAq6awX
https://imgur.com/QMqaO4l
https://imgur.com/8ZbFuQK
dqXoHvq

7VtpTwh

7ZZVHfC

kAq6awX

QMqaO4l

8ZbFuQK
 
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Any chance you can post a few pics of each gun with the magazines? I know they're compatible but its always enjoyable to see another's growing collection. Local purchases?

Welcome to the Forum!

Todd
Thanks. I tried to post pictures using the insert image tool but they don't show. Perhaps my account is too new to be allowed to post images yet.
 
Welcome to the S&W Forums. Model 39, 39-2, and 439/539/639 magazines are identical in terms of external dimensions and the location of the magazine catch notch. At least that is the case with S&W factory magazines, aftermarket magazines (ProMag and Triple K) may have some deviation from factory dimensions.
Also, the magazines for the 3904/3906 will also fit, but are a little longer to accommodate a ninth round in the magazine.
 
Welcome to the S&W Forums. Model 39, 39-2, and 439/539/639 magazines are identical in terms of external dimensions and the location of the magazine catch notch. At least that is the case with S&W factory magazines, aftermarket magazines (ProMag and Triple K) may have some deviation from factory dimensions.
Also, the magazines for the 3904/3906 will also fit, but are a little longer to accommodate a ninth round in the magazine.

Thanks. So the tight fit shouldn't damage anything?
 
Thanks. So the tight fit shouldn't damage anything?

If by "tight" you mean extra effort to seat, there is probably a minor dimensional difference in the magazine catch or the slot on the magazine causing it. Doubt it will be a problem unless you have enough strength to push the magazine through the top of the slide. ;)
 
If by "tight" you mean extra effort to seat, there is probably a minor dimensional difference in the magazine catch or the slot on the magazine causing it. Doubt it will be a problem unless you have enough strength to push the magazine through the top of the slide. ;)

I takes a little more force than what feels comfortable and it really sticks when trying to eject the mag.
 
I takes a little more force than what feels comfortable and it really sticks when trying to eject the mag.

It may be as easy as slightly enlarging the slot on the magazine, but you'd want someone with experience to diagnose and fix the problem.
 
It may be as easy as slightly enlarging the slot on the magazine, but you'd want someone with experience to diagnose and fix the problem.


439, 539, 639 should have metal baseplate and should be interchangeable. 3904/3906 early 8rd or late 9rd with plastic base should fit but will stick out slightly.

And even if you can insert it, failure to eject cleanly should be addressed or avoided.

If it sticks on ejection, I would say that is a problem with side dimensions of mag, not likely related to retention slot on mag. Also check inside of magwell for debris / damage or dirty. Insert mags with grips off to see what is going on.

If you have a set of calipers, measure cross section dimensions of both 539 and 639 mags. Betting they are not the same. Maybe aftermarket mags - any SW marking on base?
 
The base of the mags all have "S & W" stamped in the metal. Sounds like they should be compatible but the 539 has a little narrower slot. Thanks.
 
That 539 is a thing of beauty. My 39-2 is my only nickeled gun. The 9 round 639 magazines with the stepped baseplate will give you an extra round in both of your guns and fit nicely at the bottom too.

Todd
 

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My 39-2 magazines all work in my 539 and 639.
Your 539 has the short fat extractor which had a very short production run.
Pretty neat.
 
I would not mess with the catch slot in the magazine bodies, those magazines are pretty expensive these days. It could be the magazine catch in your newly acquired Model 539 is dragging on the magazine body.
 
My 39-2 magazines all work in my 539 and 639.
Your 539 has the short fat extractor which had a very short production run.
Pretty neat.

The short fat extractor was actually common in the Model 539 and much harder to find in the Model 439 & 639. The long thin extractor, like the one used in the Model 39-2, is more rare in the Model 539. My 639 mags work fine in my 539 but the 539 mags don't work in the 639. The mags from my pre-39's and 39's also work in the 539 & 639 but not vice versa.
 
I would not mess with the catch slot in the magazine bodies, those magazines are pretty expensive these days. It could be the magazine catch in your newly acquired Model 539 is dragging on the magazine body.


If you think the mag release is dragging, take the grips off and see if you can confirm - and if that is it you can adjust the depth of the release. Just dont overadjust and obviously verify it does not adversely affect the original 539 mags.

Personally I doubt this is the problem, but the whole problem sounds weird, especially since another post reports a similar (but opposite?) issue.

I did have an issue with 6906 mags not properly locking / releasing which was cured by replacing the mag release but it was not a drag issue - just would not snap to lock without a hit on mag base and sometimes would not release. I think somehow the tip of the release had been damaged.

I still think a precision measurement of the magazine cross section would tell a lot and check several places top to bottom.
 
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