MOUNTING AN ARTICLE UPON A SUPPORT

A mounting for mounting an article onto a support comprising upper and lower mounting members. Seating surfaces provided between the members retain the members in assembled relationship with the members immovably registered together in a first plane. Three spaced mounting member registration projections provide, in the assembly, contact between th e mounting members in three spaced and staggered positions on opposite sides of one of the mounting members, and registration to hold the members immovably together in a second plane. Spring-loaded locking is provided to hold the members together when assembled. Preferably the registration projections are provided on one member upon guide surfaces which are converging and inclined towards a respective seating surface. Guide surfaces on the other member are correspondingly converging and inclined. The convergence and inclination causes the projections to force the seating surfaces together to hold the members in the first plane while the projections themselves hold the members together in the second plane. One or other of the seating surfaces may have seating projections to engage the other seatin g surface. The invention is particularly applicable for use on weapons for withstanding sudden violent or vibrational forces and for quick release whil e permitting reassembly and while ensuring that settings such as calibration a nd boresighting settings are not altered.