Crosman 1377c - low pressure, pellet stick in barrel

[gametime]

My brother gave me this pellet gun, with a known issue that pellets were not firing.
I found one lodged about an inch from the breech, which I cleared.
Here's the problem... 7+ pumps, and pellet fires as normal. Anything less and pellet get's stuck. Seems to be holding pressure (~10mins), so not sure where the problem may lie.
I plan on ordering the steel breech kit soon. What else should I consider to resolve this? Or what can I check to narrow things down.
Any help would be appreciated.

s/n starts with 0985...

Thank you
Manuel

[DennisCA]

How old is it?

It's just a guess but the seal(s) may need replacing.

[Rob112o]

Your orings are dried out or you have a piece of debris stuck either between the check valve or valve stem. Which is slowly letting the air escape. You should be able to leave a pump in the pistol and it will stay in there for years. You mind as well order a reseal kit they are pretty cheap for this pistol:

http://m.ebay.com/itm/Crosman-PC77-1322-1377-2289-Seal-Kit-Bolt-Valve-Seals-Valve-Stem-Pump-Cup-/171391339230

The pistol date is dated September 1985

[gametime]

Rob- I placed an order for the kit, we'll see how that changes things.

Thank you both.

[bohoki]

yea hold a piece of toilet paper over the barrel near the back and fire it to check for leak on fire

but i bet the burst seal is bad can you feel the pressure when you pump increase

[brassburnz]

Your orings are dried out or you have a piece of debris stuck either between the check valve or valve stem. Which is slowly letting the air escape. You should be able to leave a pump in the pistol and it will stay in there for years. You mind as well order a reseal kit they are pretty cheap for this pistol:

http://m.ebay.com/itm/Crosman-PC77-1322-1377-2289-Seal-Kit-Bolt-Valve-Seals-Valve-Stem-Pump-Cup-/171391339230

The pistol date is dated September 1985

My 1377 still works well but I know the o-rings can go at any time. Thanks for the link to the repair kit. Very reasonable price.