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If the compression of the buffer were 0.500 inch instead of 0.250 inch, the necessary average force would be one-half of 12,350 or would be equal to 6,175 pounds. The time of action would then be t=¥~61875=-00458 ^

Thus, by increasing the length of the stroke of the buffer, the retarding action happens more slowly and a small error in timing will not have as great an effect.

In the computations leading to the time-travel and time-velocity curves shown in fig. 2-30, it was assumed that the recoiling parts were not moving at the instant of firing. Therefore these curves represent the conditions obtained if the buffer alone acted to stop the forward motion of the recoiling parts. On this basis, let it be assumed that the buffer used exerts an average force of 12,350 pounds and that therefore it is comprcsscd 0.0208 foot, bringing the recoiling parts to a stop in 0.00229 second (as previously computed). The recoiling parts are then returned quickly to battery by clastic action as the buffer regains its original dimensions. (As pointed out previously, most of the striking energy of the recoiling parts is dissipated in the buffer, so that there is no tendency for the recoiling parts to rebound. ) This action is indicated by the last portions of the curves in fig. 2-30. Note the small overtravel of the recoiling parts past the battery position. The total time to complete the operating cycle is 0.0522 second and therefore the theoretical rate of fire for this particular design is:

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