Marlin 39a Question

[TWHBC]

I have a Marlin 39a. Bought it used in the early 90's. Shoots well and is in great shape. Not collector but very good shooter grade. While out searching for a muskrat that has moved into my creek, and digging into the bank creating issues I sat down and was just enjoying the day, I noticed that the magazine tube has what appears to be a 1": or so tear through the metal about an 1-1/2 " from the muzzle end. It is in the space between the magazine and the barrel. No displacement of metal at the crack that bulges from the round perimeter of the tube. You have to look closely to see it? Never noticed it before, and since I have had the rifle nothing has happened that might have caused this.
Magazine holds the right amount of shells, and functions as it is disposed to.
Any ideas on what may have caused this?

[AJMD429]

Bizarre.....photo(s) would help.

Should be relatively easy to fix/patch with some JB-Weld and cold-blue though.

[Wind]

Hey there TWHBC -- The Marlin 39a family of rifles, including Mounties, has a seam that runs the full length of the magazine tube. It is not welded. It's installed with the seam under the barrel. Lateral movement of the inner tube levers against the outer tube from the muzzle to the tube hanger and will eventually split that seam. There isn't much you can do to repair it without interfering with the inner tube function. Hope this helps. Best regards. Wind

[marlinman93]

Wind is correct. I have occasionally used pliers to gently squeeze the tube joint closed, but need to remove the inner tube and do so carefully to avoid squeezing it too far and interfering with how the inner tube slips in. I wrap my pliers with electrical tape first to avoid leaving marks.

[TWHBC]

Thanks guys! Learned something new and worthwhile today, so a good day!
The seam is good at the muzzle end, and the crack starts about an inch in,, so guessing that if someone (we all know this guy ) tried to force the inner tube to latch with to many rounds in place it could open the seam near the end, as the inner tube could easily be out of alignment trying to push it in.
Glad to know nothing serious and not unheard of. Now the issue is duct tape, JB weld, superglue, maybe bubble gum?
I wonder why I did not notice it until now?
Took the Remington 512 out this morning, and noticed the magazine tube is made of a heavier guage metal than the 39a.

[Panzercat]

Haven't seen that on my 39a yet, but I'll file this one away as a 'now you know' moment.

[jnyork]

If it functions normally and is not really noticeable, why mess with it? Keep on keepin' on.

If you must, new mag tubes are readily available and not too awfully expensive.

[765x53]

Behind the knurled end of the inner tube, my mid 1970's 39a, has a short sleeve that fits over the outer tube to prevent this problem.