./ feet per second and its kinetic energy at that time has been computed to be 104.5 foot pounds. For any instant during acceleration, this value is added to the amount of energy transferred to the bolt up to that instant (from fig. 2-26). This total kinetic energy of the bolt is then used to compute the bolt velocity according to the relationship:

For the conditions of the example, W—5 pounds and therefore:

The next step is to integrate under the velocity curves to obtain curves showing the changes in barrel travel and holt travel during the period of acceleration. These travel curves arc also shown in fig. 2-25. The values given by these curves arc added to the barrel travel and bolt travel which exist at the beginning of the acceleration in order to extend the time-travel curves to 0.009 second. Fig. 2-27 shows the complete time-travel and time-velocity curves up to this point.

All of the data of interest in designing the accelerator lever may either be found in fig. 2-27 or may be derived directly from this figure. Fig. 2- 28

shows data which mav be used for the accelerator

design. The barrel deceleration and bolt acceleration curves were obtained by measuring the slopes of the velocity curves. The curves showing the relative travel and relative velocity between the

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