Break Action Revolver Question

Discussion in 'General Handgun Discussion' started by carlakeley, Jan 28, 2016.

  1. carlakeley

    carlakeley New Member

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    From what I've read the the higher you go in caliber the quicker a break action revoler's locking bar will wear out. I don't really understand why this is because you can find things like Thompson contenders in .45-70govt and many big game double rifles can come chambered in .375h&h through 700ne, and I haven't read any reviews of their locking bars failing at all. So I'm curios is there a different design being used for contenders/safari rifles or is the mechanism just larger and sturdier but will fail in the same way eventually?
     
  2. danf_fl

    danf_fl Retired Supporter

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    Welcome to the forum. Stop by the "Introductions" area and say "Hi".

    Now, back to the question.

    Companies have done a lot of research to design something. Basically, a break action handgun is the same as the shotgun (O/U or S/S).
    The metals used today are better than in earlier years and will probably last longer than you or me. How fast one can get it to break depends on usage and abuse. Most normal shooters will not have a problem.
     

  3. c3shooter

    c3shooter Administrator Staff Member

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    Top break revolvers (Iver Johnson, Harrington & Richardson, etc) were latched closed by a loop or stirrup that hooked over the locking posts. There were designed for low pressure, black powder cartridges. As higher pressure smokeless rounds appeared, the top breaks faded away in favor of the solid frame revolver.

    Pistols such as the Contender use a totally different locking system. It is not affected by an unsupported frame stretching. Locks up with a lug on the bottom of the barrel, like a top break rifle. Notice that you will find the old top breaks in .32 S&W, .38 S&W, but not .38 Special, .357 magnum, etc.

    ForehandWadsworthLeadA1000.jpg
     
  4. carlakeley

    carlakeley New Member

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    Just for clarification with what happens to the stirrup/loop lock. When fired the pressure forces the barrel forward and down away from the hammer causing the post to stretch the stirrup out eventually leading to a gap forming and failure to close issues. That about the size of it?

    With contenders/double rifles I'm guessing that there's a rod under the barrel that narrows before bulging out at the end, and the narrow part fits into a notch to hold it in place. That pretty close or am I way off base there?

    I'm surprised that a top mounted lock would have more failure issues than a bottom one. I would have thought that mounting the lock over the chamber would have created more stability than mounting it down low closer to the pivot point.
     
  5. hiwall

    hiwall Well-Known Member

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    The bottom locking mechanism on break action rifles/shotguns are massive compared to the two tiny little fingers sticking up on the break action pistols of a hundred years ago. Also just look at the picture above that C3 posted. See that free standing frame sticking up about an inch and half or two inches? Even very slight movement (stretching, bending) can lead to a none working pistol. Most break action rifles/shotguns are designed to allow for some wear or metal movement and still lock up solid and tight.
     
  6. locutus

    locutus Well-Known Member Supporter

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    There was a pretty massive lock up on my old .455 Webley. Soft steel in that era, but it was "bank vault strong" for it's day.:)