Benjamin pump pistol will not hold air

[raycalvino]

Hello Furom,

I have an old (early 80's) Benjamin pump pistol in .22 cal. I took it out yesterday and it failed to keep air in the gun. Before I went out I may have made a big mistake by putting some oil in the small hole under the handle just in front of the plunger - after reading some info, that hole may in fact be just for air and not oil, but I'm not sure.

So what do you guys suggest? I can't find a disassembly manual anywhere online and I can't find replacement gaskets listed anywhere. I guess I will attempt to strip the gun down. I see, a punch type pin at one end of the gas chamber, and that scares me a little - I don't want to ruin the gun! I may not have the tools to do the job?

Thanks so much,
Ray

[crazyhorse]

Try here:

http://www.mac1airgun.com/

[Plekto]

Very nice guys. One thing to note is that the OEM seals are not able to handle more than 8 pumps or so without doing permanent damage to the thing's velocity. So getting it tuned and capable of actually withstanding more than you'd normally require is a huge thing, IMO. So far, I've never heard of one of his custom jobs failing.