An SX1 barrel and extension are two separate
pieces. The extension is the part that inserts
into the receiver where the bolt rests. The
barrel is actually screwed into the extension.

I have one at present that has come loose. I can
just manually unscrew it.
Does anyone know how Winchester attached them.

They made some other barrels in two parts
also, like the M1200, M1400, M1500. I don't
know how they attached those either, I did
have occasion to remove some several times,
when I was building a sets of barrels for a
double I was working on. I just used a pipe
wrench and turned it off, but like I said,
I have no idea how they secured them there
in order to not have them come apart in
use.

If I knew how they attached them to keep
them tight, I would re-attach this SX1 that
has come loose. I am thinking some sort
of lock-tite would probably work, they make
some that can take pretty high temp for
industrial purposes.

I would stop by your local car parts place and pick up a small bitty tube of Loctite 290. Clean the external threads on the barrel and assemble the barrel to the extension. About one turn from proper alignment, apply that 290 to the thread juncture fairly heavily. Then tighten the barrel to the extension in proper position. That Loctite will wick all the way to the bottom of the threads. Set the barrel aside for a couple of hours, then wipe of any excess on either end that is still on the surface. It only cures when air is excluded, but it flows so well that it may get into someplace you don't want it to be. This is why you wipe off any excess.

Thanks, for the info. That is probably how I will fix it.
I suspect Winchester did something similar, but don't
know. Actually looking at the threads, it appears that
there might have been oil on them. There was some
greasy looking stuff. It might have got there after
the parts were put together though, not before,
and there is very little of it there.

We probably are not going to find out how Winchester
did it, but that is okay. I can fix it however I feel like.
I was told by Bob Baumgart that Winchester loctited
the magazine tube in. I had one them come loose
also on another SX1, and fixed it with blue loctite.
I used the blue because I did not particularly care
if it came loose again, since I could always do it
different in the future. This one, I think I will use
the red, like you suggested. Also I think that was
a pretty good tip to start the barrel on the extension
before applying the loctite. The only way to mess
up this is to not get the barrel in correct position.
The extractor slot has to be where the extractor
engages it, and the bolt hole has to be where
the bolt wants to fit into it to lock everything in
position. So once it is put together and sets,
things will mesh with it that has to mesh. Probably
best to put it on without any loctite, then put on
gun and see if bolt will close, maybe even
try to rotate the barrel some with everything
in position, then mark that position, then
remove it, then fix as you said.

It should go pretty easy to fix it.

Also it is good exercise in knowing how if
a guy ever wants to build a barrel for an
SX1, like he has one that is bulged or
whatever. Take a torch to magazine
loop, and separate. Then take a nice
Rem 1100 with Remchoke, cut the
extension off, remove magazine loop,
machine the end with threads and extractor
slot just like the junk Winchester you took off.
Then install new tube in the Win extension,
mount extension and barrel on gun, carefully
figure out where to mount magazine loop,
mark position well, remove all again,
Now silver solder magazine loop on barrel,
then drill the gas ports in, which should be
easy, the holes are already in the magazine
loop to guide you. Now attach the extension
to barrel tube as you recommended, mount
barrel to gun, and let the loctite cure. Now
you got a nice remington barrel with remchokes
on your SX1, and it says things like
Remington, 2 3/4 inch etc. right there on
the barrel.

What do you do about the original gas ports in the 1100 barrel ?Surely the new Winchester holes won't be in the same place.

Bobcat

Good question, my off the cuff answer, is the gas ports are slightly further down the barrel on an 1100 than on an SX-1, that would put the 1100 ports in front of where the magazine loop is. You could just spot weld the old ports closed, or better yet, don't use 1100 barrel, use 870 barrel, it is also cheaper.

I once built several sets of barrels for doubles by using Winchester model 1200 barrels with Winchokes. I installed the barrels in the monoblock of the double. That was back in the days before choke tubes were available in any double barrel. So, already having been there and done that, you would think I would have had brains enough to say use 870 barrels to begin with, since in the past when I did something similar I used Winchester pump barrels, but I didn't and you caught me. Good catch.

Actually you could use Win 1200 or 1300 or sxp barrels. Once I built a barrel for an Ithaca model 37 pump, using some sort of Savage barrel that I bought on Numrich gun parts for about 50 bucks, and that used Winchokes also.

WHY ?
You would wind up with a [email protected][email protected] gun and the barrel would not be made with Winchester proof Steel, would have a smaller bore size, have a welded on rib in place of the floating Super X rib and wind up with an inferior so, so choke.
Super X -1 barrels can be found and slip right on any receiver.

The magazines were installed with blue Locktite at the factory so most likely the barrel and extension were locktited also.
I would use red Locktite like Curly recommends.

CT

WHY?, Use your imagination, Finding SX1 barrels is not easy, with choke tubes is even less easy. Winchester proof steel, probably not as good as Remington, certainly no better. Floating rib, that was one very large problem on the SX-1, they floated right off the gun until the design was changed and the screw eliminated in place of silver soldering it on. Also the ones silver soldered on had the problem of sometimes coming apart if they were modified to take after market chokes. The place where they were silver soldered onto the barrel was paper thin where the rib was soldered onto the barrel, and this comes apart with barrel breaking where the rib is connected on some of these guns modified that way. I know Winchester barrels can be found, in fact I have at least 5 of them right now. On the other hand, a person with access to the tools could make up a barrel pretty fast and easy, and as far as I am concerned it would be better if it had the remington welded on rib. One of my SX-1 barrels had the rib float off, and to fix it, it was pinned on the 3 center rib posts, which was a popular way of "fixing' these floating ribs when they floated right off the gun. Then after this was fixed with the 3 pins through the rib and center rip posts, after a lot of shooting 3 center rib posts came loose and the rib floated off again. Superior design? I don't think so.

I would bet you are right about the loctite being used at the factory, but that is only a bet, not a fact, I am curious about the facts, that is why I asked. Also, I agree the red is the way to go, as they say it is good up to 300 degrees, and chambers can get pretty hot, so I suspect the blue would give up pretty quick there.

Bore size should not be a problem going from Winchester SX1 to some standard 870 barrel, I have several SX1 barrels with winchokes adapted to them, and I can use Rem chokes in those Winchoke barrels, they just stick out a little further. Also I have a Remington 870 express barrel that uses Winchokes. The dimensions of SX1 barrels is close enough to standard 870 that there is no problem.

By the way, I don't mind a gun being a basstard. In fact I like those basstards. My present SX1 has a Remington 1100 forearm on it and the butt stock is my own making. 1100 forearms can be adapted pretty easy if you know how, and there is a large supply of them, whereas the Winchester forearm is no better, harder to find, and a lot more expensive.