## Recoil Operation

The values shown in Table 2-1 can be used to determine the values for (D1 + D2) and (Di — D>) in equation 2-8 and the equation can be employed to computc the energy delivered by each spring in moving from the initial displacement to each displacement indicated in Table 2 1. For example, in moving from a displacement of 0.280 foot to 0.245 foot, the bolt spring delivers:

The energy delivered by the barrel spring for the corresponding displacement is:

The procedure is repeated for the other displacements.

The next point is to consider the energy losses in the action of the lever. To be consistent with the assumption made for the action during recoil, the total loss for the period of action will be taken as 6 foot pounds. This value is so small that it will have little effect, and therefore it can arbitrarily be distributed equally over the period, allowing the loss to increase by 1.2 foot pounds for each of the five increments being used for computation. Since all of the required energy values have now been determined, the velocities of the barrel and bolt for each displacement can be computed as follows:

The energy in the moving parts at any point in their travel is e-AM.W+^NW

But V2=RVi, where R is the velocity ratio shown in fig. 2-28.

Therefore:

Solving for Vi :

0 0