Projectile ramming apparatus includes a rammer pawl for engaging the base of a projectile with a rigidizable chain attached to the rammer pawl for providing reciprocating movement thereto. The rigidizable chaining includes a plurality of rows of links having adjacent links pivotally attached to one another. A perimeter of each link enables fixed engagement of adjacent links on each row upon coordinated pivoting of adjacent links in each row and, further, for enabling release of the fixed engagement upon reverse coordinated pivoting of adjacent links. A drive is provided for reciprocally moving the chain and for pivoting adjacent links in order to rigidize the chain as the chain is moved in a forward direction; and unlocking, or unrigidizing, adjacent links as the chain is moved in a reverse direction. The chain is moved at a generally constant velocity enabled by the link perimeter.