Headspacing a Carcano Cavalry Carbine

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Lokichoki

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Hello,
Is it possible to check headspace using feeler gauges that have been cut out round to sit on the bolt face? I've cut a couple "round shims' and gradually added more thickness till I reached the point id have to remove the extractor, which was .010. At that thickness the bolt was able to close with a snug but not forceful turn. I'm sure I'll hear that I'm stupid for doing this I was unable to get behind the locking lugs to try that way. Any info or advice or for that matter anyone with a no-go gauge they could lend (at no cost to you of course and a token of appreciation). Any help would be appreciated.

Ps: I normally just suck it up & shoot most of these imports and visually inspect the brass but this one gave no resistance whatsoever I could feel on close.
 

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If you remove the tailstock, firing pin, springs, extractor (in you case, leans towards “excessive”) and such you can get a very good feel of where the case contacts the chamber. A “gravity” close, assuming this is how it is with no case, and then a no close after adding a shim would indicate you have reached contact.

If you are shooting it and reloading for it, the way to maximize brass life is just that way. Gut the bolt and size the case so the bolt falls part way home with the lugs engaged, then stop. The case will be slightly compressed upon fully closing the bolt (you can measure exactly how much if you want). In any case, you won’t be undersizing cases then blowing them out, limiting their life. Will also reduce or eliminate the need to trim after the first firing.

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If you just want to know where things are at, the easiest way but not the most accurate (not the least accurate either) would be to get something with a hole In it that’s about the right size to hit the case in the middle of the shoulder.

Would want it to be a bit deeper hole than the one shown, so you can measure from the datum (fancy word for arbitrary hole size that works for you) with a bullet in the case.

Right that measurement down then fire the round, the case will form to the chamber and you can again measure it, to see how much it grew.

A before and after like this, will give you a measurement.

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The feeler gauge method is not super accurate because it relies on specs of whatever cases you use which probably vary a little, but it’s accurate enough I think to see if your rifle is safe. Ive used that method on about a dozen rifles because im too cheap to buy a gauge for all those different calibers. 10 thousandths is excessive, at least wear safety glasses if you choose to shoot It much.
 
I've fired it and checked the brass it was nearly perfect and tight the shoulder did move forward like .008 which is fine since I'll be buying a die to neck size only. It does shoot like 5 feet high at 50uss apararently the Fascists did grasp the concept of sight picture. So I installed a M1 Carbine front sight ;)
 
... It does shoot like 5 feet high at 50uss apararently the Fascists did grasp the concept of sight picture. ...
Actually, the secret is that the Carcano's proper sight picture is remarkably different from what we normally use today with iron sights. There's a YouTube video by a guy that discovered this and explains it. I used the sight picture as he described it and got my Carcanos to shoot very close to POA. I wish I could draw a diagram, and the explanation doesn't do justice, but it's kind of: you line up the horizontal line described by the top of the rear sight with the horizontal axis of the desired POA, then you adjust the angle of the barrel to bring just the tip of the front sight into view in the V-notch, so the base of the front sight, where it flares vertically, is NOT visible. (ie the top of the front sight is below the top of the rear sight). This sight picture will depress the angle of the barrel sufficiently to produce a POI at the POA at the zero distance of the rear sight. (300 meters for the battle-sight setting, usually, depending on model; I think it's 100 meters for the later 38 and TS models; the sight you have may differ due to rearsenalling long rifles into short rifles and carbines). The POA you use is held for bullet drop between actual POI distance and sight zeroed distance. Sorry it's not a very good explanation, but it worked for me. The guy in the video provides diagrams that make it easier to understand.
 
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If you are shooting it and reloading for it, the way to maximize brass life is just that way. Gut the bolt and size the case so the bolt falls part way home with the lugs engaged, then stop. The case will be slightly compressed upon fully closing the bolt (you can measure exactly how much if you want).

Yes.
This used to be a common means of compensating for long headspace (or belts) but it seems forgotten in the "how many thousandths off the lands" era of reloading.
 
Do appreciate the heads up on obtaining a correct sight picture for the Cavalry Model, recently purchased one from Gun Broker, and have been busy cleaning it up, plan to keep it pretty much original. I've got brass, bullets and powder as well as primers but am waiting on the Hornady dies so I can try it out. These are very interesting rifles, so I figured I better get one during the lull in availability of not only firearms, but also in ammo, like during the Obama years.
 
You can make up a set of gauges your self. Use an m die or similar to neck up a case. Put a feeler (I use .005 increments) between shell holder & die. Make a +.005, +010, etc. You end up w a nice set of gauges.
 
Anybody use the piece of paper method to set up your dies to match your gun's headspace?
I've done this on a a few rifles when setting up dies and never had any issues. You set your full sizing die, touch the shell holder, back it off some, size a piece of brass, then chamber the brass with a piece of paper between the bolt face and the brass. It should be hard to close the bolt or you can't close it. Keep repeating, sizing the brass after you screw down the die a quarter a turn each time, until you feel just a little resistance trying to close the bolt. I have a RCBS precision mic, but I find this simple, low cost method to work the best.
 
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