Popgun Pete
Contributor
Nemrod guns all use the same pump size, the decorative knurling on the tube changes on some models with the years, but it is still the same pump. The rubber seals on the pump rod piston age and crumble over time, so these need to be replaced with something else that can use an "O" ring as the original seals are no longer available. One thing that should be noted is a few hand pumps don't have breather holes as they rely on a piston seal lip reversing to draw air through the pump rod hole in the back of the pump, the Technisub pump is one of these. Nemrod hand pumps all have a breather hole on the rear of the pump tube body.
Some hand pumps such as the Nemrod seal the end of the pump tube against a washer in the back end of the gun by screwing down onto it. Others such as the Technisub seal the nose of the pump by pushing it through an "O" ring trapped in the gun's inlet valve body, while others such as Mares carry that seal on the nose end of the pump in a fitting that forms the front end of the pump. For some reason manufacturers decided to not use a universal hand pump fitting and few hand pumps fit anyone else's guns! This means that if you own a lot of guns of different brands then you will have a drawer full of hand pumps.
Some hand pumps such as the Nemrod seal the end of the pump tube against a washer in the back end of the gun by screwing down onto it. Others such as the Technisub seal the nose of the pump by pushing it through an "O" ring trapped in the gun's inlet valve body, while others such as Mares carry that seal on the nose end of the pump in a fitting that forms the front end of the pump. For some reason manufacturers decided to not use a universal hand pump fitting and few hand pumps fit anyone else's guns! This means that if you own a lot of guns of different brands then you will have a drawer full of hand pumps.