A pin retaining assembly for an advancing ram includes a retention plate and a retainer. The retention plate includes two oppositely facing surfaces and a channel with a notch between the two surfaces. The retainer includes a main body, a pin receiving slot, and at least two flanges. The main body is configured to slide into the notch of the channel and extend through a surface of the retention plate. The pin receiving slot has an open mouth through an end of the main body. A first flange extends from one end of the main body along a surface of retention plate and a second flange extends from another end of the main body along another surface of retention plate. The flanges retain the main body of the retainer in the first notch from moving in a direction defined by a longitudinal axis of the pin receiving slot.