The P315 is an advanced model based on the P305.

A distinctive design feature is that the red-circled area in the image has been enlarged and shaped into a ring-like frame.

This model releases by pushing up the rubber band with a releaser. It inherits the multi-shot system from the P305 TSUN-TSUN, where the releaser's position and protrusion angle adjust according to the remaining rubber bands. The top of the frame features ten notches, which serve as holding points for the rubber bands.
The releaser, which protrudes from the rear end of the hold, is under constant spring tension to return to this position.

Before loading the rubber bands, the releaser needs to be positioned at the front of the hold. To facilitate this, a locking mechanism has been added, eliminating the need to continuously hold down the releaser with a finger, as was required with the TSUN-TSUN.

Load 10 rubber bands into the hold. When the lock release knob is pushed up, the releaser leans against the first round, completing the releasing preparation.

All that’s left is to pull the trigger. The releaser, linked to the trigger, pushes up the rubber band while rotating forward to release. After releasing, the releaser quickly leans against the next round, ready for the next shot.

At first glance, it may be difficult to distinguish the trigger and the grip. The round part is the trigger, and the brown part with anti-slip grooves is the grip.

This is from the opposite side. Except for the releaser's locking mechanism, the design is symmetrical on both sides.

The mysterious part at the rear is for hooking spare rubber bands to keep them handy.

Three hold pin positions have been added to adjust the tension of the releaser spring.

The main body panel is made of maple, the grip is black walnut, and the reddish core material is Japanese zelkova. Other mechanical parts are made from beech and birch plywood as needed.

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