Rechambering a Martini rifle

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  • CZ evo3

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    May 17, 2017
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    I have a martini that was re-barreled and chambered in .357 magnum. I want to have it reamed out to .357 Rem Max. Is this a project for an amatuer/beginner, or should I leave this to a professional?
     

    IndyDave1776

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    Jan 12, 2012
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    The outer case diameter is the same. The case should headspace on the rim, which is the same. The question is whether or not you believe you can ream the chamber deeper and run true with the bore, and you are the only one in a position to know the answer to that question.

    Most people would probably tell you that if you have to ask you probably shouldn't, but I am not going to presume to answer the question. After all, you are the one who will be holding it up to your face.
     

    55fairlane

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    New Haven
    If you have a set a head space gauges,and a pull thru reamer......remember to check head space, with out extractor, firepin,ect......personally I'd keep it 357 and shoot it......

    Aaron
     

    Leo

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    Mar 3, 2011
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    If you have a set a head space gauges,and a pull thru reamer......remember to check head space, with out extractor, firepin,ect......personally I'd keep it 357 and shoot it......

    Aaron

    +1

    I have done similar things making some ackley improved wildcats. IF properly set up, it is not too tricky of a job. Getting properly set up will likely be as expensive as just having a gunsmith do it for you, which will not be cheap. (who has a roughing and a finishing rifle reamer set up for that caliber just sitting on the shelf?)

    I am assuming your old Martini was a .310 cadet. I like the idea of adding another 200 plus fps to the velocity in a rifle length .357. Are you loading your own with very slow powder, or shooting factory? I have seen an article where .357 ammo designed for a handgun, gains some with the carbine/rifle barrel lengths, but really comes into performance with powders designed for longer barrels. Custom ammo might get you part way there without buying reamers.
     
    Last edited:

    jcj54

    Marksman
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    Aug 24, 2013
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    To properly do what you want means removing the barrel, lengthening the chamber and re-installing the barrel. The issue you have is whether the long round can be inserted in the chamber without nodifying the top of the breechblock.
     

    CZ evo3

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    May 17, 2017
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    Carrollton
    +1

    I have done similar things making some ackley improved wildcats. IF properly set up, it is not too tricky of a job. Getting properly set up will likely be as expensive as just having a gunsmith do it for you, which will not be cheap. (who has a roughing and a finishing rifle reamer set up for that caliber just sitting on the shelf?)

    I am assuming your old Martini was a .310 cadet. I like the idea of adding another 200 plus fps to the velocity in a rifle length .357. Are you loading your own with very slow powder, or shooting factory? I have seen an article where .357 ammo designed for a handgun, gains some with the carbine/rifle barrel lengths, but really comes into performance with powders designed for longer barrels. Custom ammo might get you part way there without buying reamers.

    To be honest, I've only fired this martini once. When I was a kid, I had a cadet chambered in 17-222 rimmed. I miss it, but couldn't afford the imported brass ($4 for each case in the early 1990s). I have a 19" contender bbl by Bullberry chambered in 357 rem max, and i have fallen in love with the cartridge. I have Tug Hill Cartridge Co. load my ammo for the rem max to be fired out of rifle length barrels.

    If rechambering isn't a viable option, I don't want it.
     
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