Been a while since I heard of Bearmat, but I remember it well. I was a platoon commander and later XO in C Co, 3d Tank Bn, at Stumps from 79-83. We were equipped with the M60A1 Rise-Passive Tank. The M60 had the M-68 main gun, 105 mm. My Plt. Sgt, Gy Sgt Mike Gratton, and the the other Tankers, informed me that when we went out on CAX's (Combined Arms Exercises) the cheapest round we fired was HEP (High Explosive-Plastic) and it cost approximately $700-800. Firing HEAT (High Explosive Anti-Tank) or SABOT was off the scale. Therefore the Brewster Device. It was a reworked 105 mm shell casing, with a single shot 22 installed in the casing, boresighted to fire down the main gun tube. Our platoons could go to a scaled-down firing range, with scaled down targets, and practice engagements. The device would fire 22 calibre ammunition (hence having to get clearance from "Bearmat"), the crew would get practice at crew drills and target engagements, and the Corps saved a lot of money on ammo and fuel.
Ronald D. Jacob
USMC 1970-1984