proditto
Well-Known Member
The photo shows left to right. A .50 MG tround ,a demo "rock breaker" triple tround, a triplex H&R tround and finally a standard .38 tround. The "rock breaker" has three ceramic pointed projectiles. The "gun" was lowered down an oil drill hole and fired to break up a hard layer of rock. The H&R triplex has three projectiles not the normal SPIW flechette tround. The gun was very heavy with its three barrels and failed the first safety check. The .38 tround was the only "standard" volume produced round. The low pressure allowed the open cylinder system to work.