Thread: Lock Time?
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Old January 22, 2013, 12:03 PM   #22
Scorch
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Join Date: February 13, 2006
Location: Washington state
Posts: 15,248
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Now the Anschutz barrels are back to 26 inches. I've no idea why. Maybe it's an accuracy issue.
With match rifles that use iron sights, it is a sight radius issue, the longer sight radius gives better accuracy. In a match, that is important.
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the spring, not hammer mass, determines the energy of the hammer strike
Kinetic energy= 1/2 mass X velocity squared
Momentum = mass X velocity

You may notice in both equations, mass figures prominently. The mass of the hammer is the primary cause of induced vibration. In older cartridge rifles, the mass of the hammer is a carryover from percussion rifles, heavy leaf springs, and thick primer cups. John Browning demonstrated that the heavier hammers were not necessary, his 1878 design that became the Winchester 1885 High Wall had a much lighter hammer, and dominated target shooting in the last decade of the 1800s, beating out the Sharps, Remingtons, Ballards, Wessons, and Marlin rifles.
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I was trying to shoot small groups with a Ruger #1 single shot rifle from the bench and as I squeezed the trigger and the sear released, the hammer fell but the round did not go off.
The image in the scope jumped a couple of inches from the vibration caused by the hammer fall. I dry fired it on purpose again just to see that again.
Yes, Ruger #1s have a large, heavy hammer. Consequently they have a lot of vibration caused by the hammer fall.
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The shorter the lock time, the less time there is for the gun to move off aim during the firing process.
Also, if you have a heavy and slow hammer, the reaction to the hammer fall can cause considerable movement during the hammer fall along with the sudden release of pressure on the trigger finger.
Do not confuse cause and effect. Slow lock times with heavy strikers causes large amounts of vibration, which translates into POI movement because they casue the barrel to move. You will have little time to move your muscles very far during hammer fall, but the movement casued by the movement of the heavy hammer is immediate and noticeable.
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There's two "times" critical to accuracy.
Correct, Bart. I usually hear them referred to as lock time and dwell time, but terminology is irrelevant. Lock time affects accuracy by reducing the movement possible during striker fall, dwell time affects movement during bullet travel in the bore. You want both to be short and vibration-free. This is one of the reasons benchrest shooters want fast locktimes, light weight strikers, and fast cartridges.
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