45 cycle time

Discussion in 'Technical Questions & Information' started by wdbf, Nov 13, 2004.

  1. wdbf

    wdbf New Member

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    Not that this would make any difference to my shooting, but what is the typical cycle time for a 45 ACP, not a race gun, just an ordinary 1911-type pistol? Assume a 230 gr military-equivalent load, not +p. By time, I mean starting from when sear breaks to when slide goes into battery with next round.
  2. inplanotx

    inplanotx New Member

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    Do a Google search at the bottom of this page. You will probably find it faster than we can explain "lock time".
  3. Pistolsmith

    Pistolsmith New Member

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    Google produced nothing on cycle time for the 1911.
    Little wonder, since it varies over a wide time scale. The fastest cyclical time would be in a chrome plated pistol, the slowest in a pistol fitted with a recoil spring having a full length follower and buffer.
    I timed this out once, many years ago, by using a pair of micro switches, a machine rest and an Oehler Model 10 chronograph that read out in milliseconds of delay. Unfortunately, I cannot find the article.
    If you rig a Ransom rest with a micro seitch set to close when the hammer begins to fall tripping the first screen circuit and a lightly sprung micro switch, having a lightly sprung easily moving inertia block, to close and trip the second screen as the slide returns to battery, a modern chronograph will read out comparative action times as velocities, but the setup may break up the micro switch mountings every shot, unless you figure out a better system for securing the switches than I had.
  4. inplanotx

    inplanotx New Member

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    Maybe you need to produce a search in the area you are searching for. Here is one.

    lock time

    Maybe I should have specified "do a search for 'LOCK TIME"'

    Sorry!
  5. Pistolsmith

    Pistolsmith New Member

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    Lock time is the amount of time between sear release and striker fall. As the question was about cycle time, or the time between sear release and one complete cycle of firing, extraction, ejection, feeding and slide return to battery, quite a different thing.
    I understand your suggestion; I use Google every day, and it is the most complete search engine for my purposes.
    My point, however, is that probably, no two 1911 pistols have exactly the same cycle time. Many things can make a slight retardation of functional speed.
    A general, and probably useless, method of determining relative cycle times is to measure the distance ejected cases travel through the air before they strike the ground; the farther from the pistol, the faster the slide was traveling.
    Does anyone know of a firearms engineering book that covers this subject?
  6. stash247

    stash247 New Member

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    While I cannot offer a source for finite, quantitative numbers, the shorter the slide, the shorter cycle time, which is why the Detonics, Officers Model, Defender, and such have such ferocious mag springs.
    If this is not a "right now " question, I'll do some research and get back to you.
    Search suggestion- Ed McGivern- trick shooter for S&W, years ago, said he used the revolver because the semi-auto would not shoot as fast!
  7. Pistolsmith

    Pistolsmith New Member

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    Yes, but.......Many years ago, in GUNsport magazine (late '60's), there was an article by one of the editors about McGivern's feat. (It wasn't by me.)
    The 6 shots in 2/5 second was attempted via an electric motor and an eccentric contacting the trigger. The result was that the S&W revolver could not cycle that fast, either.
    We are talking about the old, "pre-war" long stroke Smith. The re-set time on the spring-loaded hammer/trigger/rebound slide devoured the 2/5 second time, leaving nothing for the trigger strokes. Besides friction, there is a very slight inertial delay that contributes to slowing the S&W action as the parts rebound, and that lengthens the cycle time.
    "Fitz", Colt's premier gunsmith made up a couple of revolvers for McGivern on the .41 frame. He used them a lot, and that must have caused D. B. Wesson much lack of merriment.
    McGivern claimed, in an interview, that he kept his eyes on the sight picture for the entire time he was firing. You can watch the famous film of him in action and see for yourself that some of his shots were made with the revolver well below and to the side of his line of sight. He must have had eyes in his shooting hand.
    I just watched some of the top pistol shooters firing a match on TV. Most of them used the 1911. Even Munden can't shoot as fast as they do, using a modern wheel gun, let alone beat a top rated shooter with an Officers ACP.
    It broke my heart, as a kid, to learn from contemporaries that Annie Oakley used shot cartridges in her .22.
    2/5 of a second? I can't whack my stop watch that fast! And how does one calculate mental reaction time? Go figure.
  8. CountryGunsmith

    CountryGunsmith New Member

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    This is a patently unanswerable question. Too many variables involved. Even the quality of slide-to-frame fit will make a difference. Hand-held vs machine rest will make a difference...

    I would imagine that a half-second would be in the ballpark.
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