Help needed Air Match mod 600 pistol

[airgunner.177]

I’ve now got the pistol totally stripped and most of it is still n really good condition apart from the end has broken off a little slide that goes from the barrel to the rear of the valve bodydont know if it has anything to do with cocking the trigger mech or not?
And I’ve noticed a small hole at the rear of the valve body with a little steel flap above it that moves up n down air just gushes out of this hole when I push the piston forward and cover the transfer port so I presume something is missing from that but don’t know what it is, so if anybody can help with with these two issues it’s much appreciated

ATB Andy

[Benelli B76]

I’ve now got the pistol totally stripped and most of it is still n really good condition apart from the end has broken off a little slide that goes from the barrel to the rear of the valve bodydont know if it has anything to do with cocking the trigger mech or not?
And I’ve noticed a small hole at the rear of the valve body with a little steel flap above it that moves up n down air just gushes out of this hole when I push the piston forward and cover the transfer port so I presume something is missing from that but don’t know what it is, so if anybody can help with with these two issues it’s much appreciated

ATB Andy

Andy, I am sure the little steel flap should close off when the dry fire lever is switched over to live fire position. The dry fire position dumps air so there is no compression on cocking for trigger practice only.

Baz