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ttowe · New Member

Hi all,

I'm new to this forum, but I was hoping someone here could help. I just replaced the O-rings and quad seal in a vintage Crosman 1400 .22 cal, early 1970s model. I had read that it is best to store these old pump ups with one pump of the cylinder, to keep dust out and to pressurize the seals. I did so, and the next morning I was curious to see if it held air pressure overnight. I squeezed the trigger (without a pellet in the barrel) and there was not any air discharged. I assumed the air had leaked down, so I pumped it once, and immediately squeezed the trigger to find a rather strong discharge of air was released (again, no pellet in the barrel). Working with the gun a while, what I found was that usually, only pumping once, there was not a discharge. Only seldom could one stroke of air be released by pulling the trigger. Occassionally, if you squeezed the trigger and held it for say 20-30 seconds, the air would finally release, especially if you shook the rifle a bit. It always discharges with two or more pumps. And it will hold a charge of say 3-6 pumps for several hours without seeming to lose power. Does this sound normal, or do I have an issue with some seals or the firing mechanism? Not sure if there should be enough air on the first stroke to cause the gun to fire or not. And I don't have a chronograph to check to see if I get consistent velocity with any given pellet. This gun has a safety and I always store it on "safe" and without a pellet in the barrel.

Thanks in advance.

Big Bore Bart · Member

Crosman's manual says to store with no air in the gun. The way the valving works, keeping a pump or two in it, is harmful to the seals. The Quad seal can bond to the nipple and tear on the next shot. with no pressure on the seal the risk of sticking is reduced.

As for the pumping, the valve has to "set" before it will fire. the first pump sets it, but doesn't generate enough pressure to overcome the spring.

lampy · Veteran Member

From your description it sounds like it may not have enough pressure in the valve with one pump to overcome the spring that holds the valve closed. The second pump is putting enough pressure in the valve to overcome the spring that closes the valve after it is fired.
The valve in these airguns is called a "self cocking" valve. There is a spring that closes the valve (the cap with the Quad ring) after firing the air pressure in the valve is less than the spring pressure and the spring pushes that cap back closed and the sear holds it closed while you are pumping it up.
If I remember right mine wouldn't shoot dependably with less than three pumps in it.
In my opinion it is working correctly.

EDIT:
I see Bart beat me by a few seconds, I don't think leaving it pumped up is necessary, but if it makes sense to you to store it with a pump or two in it I don't think you will damage it.

lampy · Veteran Member

I thought about the whole store it with pressure in it thing some more.... With the spring that closes the valve after firing and the spring that holds the check valve closed the valve is sealed up with no air pressure in it. I can't see how any dust or debris is going to get into the valve....

ttowe · New Member

Thanks Bart and lampy for the quick replies. Sounds as though I should leave well enough alone. The gun seems to have plenty of power with the new seals. I think I will store it in a gun case anyway to keep it from being exposed to dust, so I will take your advice and not leave a charge or air in it when it is not being used.