Bore evacuators, i.e. chambers disposed around barrels for storing part of the combustion gas and subsequently injecting it into the barrel to provide suction

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Cooling or heating systems; Blowing-through of gun barrels; Ventilating systems > Evacuating combustion gas from barrels (F41A13/10 takes precedence) > Bore evacuators, i.e. chambers disposed around barrels for storing part of the combustion gas and subsequently injecting it into the barrel to provide suction