FKDXX pounds

The velocity gain due to this force would be:

The effect of this gain in velocity is shown in fig. 2-32 by the curve designated as step 2. The curve designated as step 3 shows the change in bolt travel that would result from this velocity. Since the bolt is now moving forward, the effect of the spring constant is to decrease the force on the bolt. Therefore, the change in velocity determined by the method of step 4 must be subtracted from the curve obtained in step 2. The modified curves are designated as step 5. Since the change in the travel curve is so slight, it is not necessary to perform step 6 and the curves designated as step 5 represent the effect of the bolt driving spring on the bolt motion.

NOTE: The validity of the foregoing method may be seen by examining the equation expressing the change in velocity of the bolt due to the effect of the driving spring:

Jo M Jo

dt where: D is the total distance the spring is compressed at the start of the forward motion and d is the forward movement of the bolt from its rearmost position.

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