Vent sealing tubes In most breech loading guns it is essential to stop the erosion of the metal of the vent by preventing the escape of gas through it when the gun is fired. For this purpose the charges in such guns are ignited by "vent-sealing tubes." For muzzle loaded guns and small breech loading guns radially vented, especially those using black powder, the amount of erosion in the vent is not so serious. The charge is fired by ordinary friction primers, which are blown away by the escape of gas through the vent. In all guns axially vented, vent-sealing tubes, which are not blown out, must be employed to protect the gunners from injury. This 'vent sealing' name remained part of British nomenclature, rather than a clearer name of 'primer' or 'firing' tubes, as used elesewhere.
Vent sealing tubes In most breech loading guns it is essential to stop the erosion of the metal of the vent by preventing the escape of gas through it when the gun is fired. For this purpose the charges in such guns are ignited by "vent-sealing tubes." For muzzle loaded? guns and small breech loading guns radially vented, especially those using black powder, the amount of erosion in the vent is not so serious. The charge is fired by ordinary friction primers, which are blown away by the escape of gas through the vent. In all guns axially vented, vent-sealing tubes, which are not blown out, must be employed to protect the gunners from injury. This 'vent sealing' name remained part of British nomenclature, rather than a clearer name of 'primer' or 'firing' tu?bes, as used eles?ewhere.