Is this Normal?

[jermzy]

Hey guys first post here. I have an 870 Police magnum and one little cosmetic issue has always irked me a little. On the factory magazine extension there seems to be some exposed thread after tightening it down. Its on there tight too. Gun cycles fine. But ive never seen another 870 with it. Is there some under lining issue I should be worried about? Thanks in advanced guys.

[72Cheyenne]

I have an 870 Express with the same +2 extension. No threads showing on mine. When you assemble
the extension remove the nut and screw it on till it locks the barrel down. Then install spring and extension
tube. Rotate the tube some and tap the lock nut area. This should settle the spring so it doesn't get caught
in the gap inside. I usually tap 2 or 3 times at intervals during install. Hope this helps.

[jermzy]

Thank you for the suggestion. I tried this just now a couple times and the threads still show, But thanks again for the suggestion.

[72Cheyenne]

If the tube is tight and bottomed out, I don't see it being a problem.

Sent from my two-story outhouse.

[jermzy]

If the tube is tight and bottomed out, I don't see it being a problem.

Sent from my two-story outhouse.

Yeah that is how I have been looking at it. I guess its just my OCD.

[Synchronizor]

It's not going to cause any problems. In fact, it's a good thing to have an extra turn or two of thread. The total length of magazine tube and extension tube thread is supposed to be greater than the length of thread in the coupling. Screw the extension onto the magazine tube with the barrel removed, and you'll see what I mean. This is to accommodate minor dimensional variances in magazines & barrels, or the added thickness of under-cap parts like sling plates or lockwashers. These extensions need a good, tight internal lockup between the two tube sections, and if there wasn't a bit of extra thread to work with, certain barrel & accessory configurations would result in a gap that could cause feed hang-ups.

[12GAfun]

It's not going to cause any problems. In fact, it's a good thing to have an extra turn or two of thread. The total length of magazine tube and extension tube thread is supposed to be greater than the length of thread in the coupling. Screw the extension onto the magazine tube with the barrel removed, and you'll see what I mean. This is to accommodate minor dimensional variances in magazines & barrels, or the added thickness of under-cap parts like sling plates or lockwashers. These extensions need a good, tight internal lockup between the two tube sections, and if there wasn't a bit of extra thread to work with, certain barrel & accessory configurations would result in a gap that could cause feed hang-ups.

I took off my Remington Mag tube kit because all I had was issues with it, would not stay tight, come unscrewed while shooting and would not allow me to completely load the tube with all 6 shells. I went with a Wilson combat Scatter gun Tech and this one works great. No need for a mag tube clamp either, has one built in here is a pic.

Well sending it back to Brownell's, today at the range shot like 30 shells, some slugs game loads and a few 00buck and the plate now rattles like crazy and the tube would come unscrewed. I just here recently took it apart and now know why it was coming loose at the range. Inside my cleaning kit was the wave washer I did not put it back on the last time I shot it after cleaning. That has been a month if not longer. I had to purchase that washer at my local gun store a few days after receiving the kit. I was not sending it back because of a washer that costed me like a bit over $1.00.
Now I am sending it back because of the rattling huge metal plate that keeps getting in my way sometimes when I pump it. just don't like that metal plate anymore. Exchanging it for a Choate +3 mag tube kit. Will post pics and performance when I get it.