Carcano project

[mickri]

Instead of putting this in my small ring mauser thread I thought it best to do a separate thread for the carcano. The Japanese carcano type I (pronounced "eye") uses a mauser style trigger guard with a double stacked magazine like the large and small ring mausers. I like the looks of this way better than the single stack carcano trigger guard that you have to use the carcano clips with. I had been planning to modify a mauser trigger guard to fit the carcano receiver because I had never seen a type I trigger guard for sale.. I saw some posts online where people had done this. It involved cutting the mauser trigger guard apart and welding it back together to fit the screw spacing of the carcano receiver. And machining the receiver to fit the tigger guard. Then out of the blue 3 carcano type I trigger guards showed up on Ebay. The seller cut the their asking price by 10% and I bought one. Even with the type I trigger guard you still have to machine the bottom of the receiver to fit.

I have to go from this.


To this

The question I have are how do I hold the receiver on the mill's table? And how do I set it up so that the bottom is not tilted to one side? The top of the receiver does have a short section that appears to be flat where the bolt handle passes through the receiver. The magazine slot appears to have vertical sides and flat across the bottom of the slot. Other than the magazine slot there are only two holes through the receiver for the trigger. One appears to be 1/4" wide and the other might fit a 10-24 screw. To complicate matters the flat on the top of the receiver is lower than barrel end of the receiver.



Suggestions please

 

[Ulma Doctor]

i'm no gunsmith, but i believe mauser and other manufacturers use jigs to secure their actions for machining

you can replicate a pinch clamp to grasp round sections, but other features may take a lot more planning to grasp
perhaps if you had the action wrench, it's concepts may be able to be used in the manufacture of a jig

 

[mickri]

I made an action wrench. I doubt that any of the sides of the wrench are square to the receiver. Didn't need to be for an action wrench. There is some wiggle room so that if I could could get the receiver square to the table I could hold the action wrench in the vice and make a machinist jack to support the other end of the receiver. I don't think that this has to be that precise. But what do I know.

I hadn't thought about using the action wrench. Thanks for the suggestion.

 

[mickri]

Here are pictures of the carcano receiver modified to fit a mauser trigger guard.



An interesting feature of the carcano is that there are steel pillar blocks in the stock. You can buy them. The ones I have seen look pretty ratty. I wish I knew how long they are because I could make some.

 

[mickri]

Mike thanks for the suggestion to use the action wrench to hold the receiver. Tried it this morning in the mill vice and it looks like it will work. It is even holding the receiver fairly level side to side and front to back without any fiddling with it. Within .003 to .005. I can flex it by pushing on the end of the receiver. So will need to come up with something to support the end of the receiver. Looks like it is time to make a machinist jack.

 

[mickri]

Here is the setup I am thinking about using. The machinist jack I made from stuff I had laying around that I bored and tapped for a 1/4 -20 bolt that would fit through a hole in the receiver. The front of the receiver is held by my action wrench. Front to back the receiver is level. There is around .003 difference side to side. That could be either I don't have it set up level side to side or it could be the tolerance from the original manufacture. When I tighten the action wrench is when the .003 shows up.



Any red flags jumping out?

 

[mickri]

Machined the receiver to fit the trigger guard this morning. Came out ok. I still have to widen the magazine slot. Will do that after I get a magazine spring and the follower. Might have to make a follower. Have not found a type I follower and the similar mauser and arisaka followers have exorbitant prices. The bolt body was covered with rust. I feared the worst expecting to find lots of pitting under the rust. Very little pitting under the rust. I am in process polishing the bolt body. Will post a picture when I get it done.

 

[macardoso]

Work holding is definitely an art in itself. This would be a good candidate for making soft jaws on your mill vise. Basically aluminum or mild steel jaws, pre machined to fit the receiver. You can even mill in a bore to zero on.

 

[mickri]

I tried some soft jaws and some V shaped jaws. Finally went with the action wrench which turned out to be pretty square to the receiver and held the receiver better that the other things I tried. Put together a makeshift jack out of a big hunk of aluminum and a 1/4 - 20 bolt.

 

[john.k]

The Jap 01 s are real sleepers of the milsurp world ......mostly in as new condition,as the Japs wernt prone to using non standard guns...Built in Italy to the highest standards of inspection,they are up to commercial finish......And the best part ,they are quite cheap ,as collectors of Jap military guns arent much interested in them.