22lr to 22wmr?

Discussion in 'Gunsmithing Forum' started by highwalljim, Feb 11, 2020.

  1. highwalljim

    highwalljim New Member

    Can a person convert a 22lr to a 22wmr just by reaming the chamber on a single shot bolt gun?
  2. BVAL

    BVAL Well-Known Member

    Yes and No,
    Barrels by themselves are not the main problem. Bore is only 1000ths differents between 22 and 22mag. The mag bullet will go through no problem.
    First, would be how old of a firearm is it? Some of the older steel can't handle the pressure. 22mag produces at or just above twice the pressure than 22lr.,,,,, the bolt has to handle the pressure also.
    Now, here is where the problems come to a head, that being the bolt itself. Most bolt faces have a recess in them where the rim of the case fits into. 22mag case has a larger dia. rim. 22mag also has a thicker or higher height to the rim, the recess has to be deeper.
    Now let's go back to case rim dia. You just made the recess and dia. bigger, now you are going to have a case extraction problem, it was setup for standard 22lr,,,,,,,,,how about where the firing pin comes through the bolt face,,,,and hits the rim in the right place to have the round go off. It is still in the same location, but hits the 22mag case more inward and not so much on the rim alone. Now if we can get these to items to be some what working right,,,,,,,how about the firing pin spring,,,,does it have enough force to hit the rim hard enough to have the round go off. Remember, the 22mag case rim is a lot thicker and heavier material (brass) than the paper thin material on the 22lr.
    So can it be done, yep, as long as the steel can handle the pressure, then it becomes a lot of work though to get that bolt right. IMO, it would be better in the long run just go find a nice used 22mag and go have some fun.
    I will add, if you asked about a single shot break action, you could get this conversion done in about a few hours, the action face (where the firing pin comes out) is flat.
    Last edited: Feb 11, 2020
    OLD Ron, towboater, danf_fl and 3 others like this.

  3. sheriffjohn

    sheriffjohn Well-Known Member Supporter

    I daresay a single-shot .22 mag or .17 bolt action would be a solid seller - not a fancy gun, just plain Jane bolt action like most of us started with. Herters' years ago offered a single-shot bolt action in .22 hornet and .32 - 20. It had no buttplate. I've looked for many years but never found one. They were less than $50. The last .22 I sold was an old Springfield single-shot bolt gun, bought by a coon hunter who said he'd been looking for just such a gun. Anyway ..
    OLD Ron, towboater and RKB like this.
  4. highwalljim

    highwalljim New Member

    thanks so much for info thats what i thought just needed a second opinion
  5. c3shooter

    c3shooter Administrator Staff Member Admin Moderator Lifetime Supporter

    22 WMR usually has a slightly faster twist rate than 22 LR.
  6. JTJ

    JTJ Well-Known Member Supporter

    Also is the opening long enough to fit the 22 mag. Simpler to buy Velocitors or the hyper velocity Aguila ammo if you need a little more power.
    If you need a budget 22 mag look at the Rossi RB22M. On Gallery of Guns the out the door price is $155 where I live. Probably cheaper if you have an Academy or Rural King store near you.
    c3shooter and OLD Ron like this.