Help needed: changing Carcano (Model 38 91/38) rear sight

[oldpewpewpew]

Hi All

I've recently acquired an old Carcano Model 38 (91/38) that needs a bit of TLC.

One thing I've noticed (there are a few things I've noticed! But this is the one that's giving me trouble) is: someone bubba'eded the rear sight. Specifically, the little metal ridge at the front of the sight that secures the rear of the top (wood) hand guard has been filed off.



My question: how do I remove the rear sight (see pic below).



I've removed the rifle from the stock. I applied penetrating oil over few days. I removed the screw in the rear sight - I am not sure what it does yet, but it seemed like a smart thing to do, before I started tapping it. I then tried to tap it out with a brass punch... No luck. I didn't 'insist' so to speak, in case I am missing something and left it alone for now.

I was also thinking about applying heat to it and give it another go, but I thought I'd ask here first.

Is there something that I am missing. A trick to it? How can I remove the rear fixed sight on Carcano M38 carbine?

Thanks heaps!

Information

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[browningautorifle]

Isn't it soldered in place? Heat and tap...

[oldpewpewpew]

Thanks, browningautorifle. This is the bit I wasn't sure about and really hoped it wasn't. Oh well, it's blowtorch time I guess.

[browningautorifle]

blowtorch time

Soft solder I think, nothing too stressing...

[oldpewpewpew]

I'll post progress...

[oldpewpewpew]

Okay, as promised. browningautorifle, you're spot on.

I wanted to remove and replace the rear sight. First, remove the rear sight screw. The screw runs through the sight and the body of the screw sits inside a small grove cut in the barrel (more on that later), but the screw needs to be removed before moving the sight or it will end in a damaged barrel.

Blow torch treatment and eagle eye - heating and watching for solder to start coming out from under the sight... Once I saw what looked like flux bubbling, I started tapping. The rear sight was sitting on there pretty tight, almost swaged, so I used a large brass punch and a hammer to tap it from the top and bottom, to avoid jamming it. It popped off with a few solid taps.

Tip, because it was going on and off when I was trying to align it. Do not tap it out by pushing it down the barrel. Hit it from the side and downwards angle, as if it was screwed on. It comes off a lot easier that way.

Since I had the replacement sight, I had a look and knew that it's not going to come off the barrel unless I remove the front sight as well.

The front sight is soldered on with a small piece of solder that sits at the top, under the front front post. Heating the top of the front sight was enough to tap it out (the entire sight/band, not the post). It doesn't look like it, but the barrel is actually cut in a way that there is a ridge that will prevent the front sight from moving further than it has too when it's reattached.

Reattaching, back to the rear sight barrel grove for the screw. My understanding is that it's there to (a) secure the sight and (b) centre the sight. The screw will not go in unless it's perfectly aligned to the grove and that will centre the rear sight. I skipped the bit about fluxing and soldering, but there's a lot of YouTube videos about that. After the rear sight is on, the front sight can be reattached and then centred using the rear sight as a baseline. Again, skipping over the soldering and fluxing part, but something worth mentioning, I melted some solder into a small drilled out cavity on top of the barrel, which is there for the solder. It should align with the same cavity (filled with solder) just under the front sight. Alternatively solder can be added to the sight band itself, but there's no point.

About 5 minutes to remove everything.
A solid 10 - 15 minutes to messing around with rear sight alignment. The screw will not go in, unless it's perfectly aligned. There should be absolutely no force, just push it in with your finger. If it's not going in, the sight is not aligned. That required some solid hammer hits to move the sight back, up the barrel and then left and right into alignment. The way I under up doing it, is I popped the screw in and held it in with my thumb, as I punched the rear sight up the barrel. Once the screw freely slotted into the hole, I knew I centred it.

Thats about it...

[browningautorifle]

Thats about it...

Thanks for all that, sounds like doing up a K98 or a rear sight for a #1Mk3...or a Brno sporter...