Crosman 1300 Medalist II

[mudduck48]

I recently bought a Crosman 1300 Medalist II. I pumped it and found out it worked. I pumped it up 7 times and shot my pellet at 5 yards and almost hit the center. I thought, O-BOY, it works. Set it up on my bench and shot about 15 shots trying to sight it in, when I noticed that the roll pin for the pump rod was coming out. Set the gun on my small block of wood with the hole in it and took a small hammer and knocked the roll pin back in. Pumped it up again and poop,HUH? It quit working. I'm beating myself up trying to fix this thing. Cleaned, changed o-rings, etc and I can not get it to work again. Has any one here rebuilt a Crosman 1300 Medalist II before? What do I need to do to get this thing working again? Thank you for your help.

[1377x]

your quad seal is probably shot

[mudduck48]

your quad seal is probably shot

That is what I'm thinking also. I just read a thread on Airgun1 by Lampy and he said that he has used a 008 o-ring in place of the Quad-ring. I might try that.

[eric]

what is it doing or not doing --- saying it isn't working means what ?? assuming you changed ALL the o-rings and ALL the seals then there shouldn't be a problem . does it hold a charge or is air escaping before a shot is fired. possible issues ... the qual seal is damaged, where the seal sits is damaged, the check valve is damaged/deformed ,the valve spring or hammer spring is toast .

qual seal is on the INSIDE

[mudduck48]

What gets me is, the gun worked for about 20 shots until I knocked the pump rod roll pin back in. Then it would only put one pump of air and any more pumps, you could hear the air coming out the barrel. I have taken the thing completely apart and change the o-rings. I have put the bottom halve back together and pump it, it is not holding air. If it was "working", it would be holding air and it is not.