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lampy · Veteran Member

I wanted to try an upgrade to the brass bushings I used in the pump linkage on this build. Early in the testing I had some trouble with the bushing at the muzzle end of the linkage, the split pin was eating away at the brass and making the hole egg shaped. I replaced the bushing and made a solid pin from drill rod. This fix seemed to be working but I wanted to try something else.
A little bit of searching found a shielded bearing (R166-ZZ) 3/16"X3/8"X1/8"
a perfect fit for my linkage.

Two bearings for the muzzle end since it is 1/4" thick, one bearing for the piston end. There wasn't enough metal to replace the center bushing.

I bored the bushings out to .375", I wanted a light press fit but the bearings slide through the bored holes.

I used a punch to shrink the edges of the holes after the bearings were installed.

I checked the pumping force before the mod and it was at 29 lbs at 6 pumps, after the bearings were installed it dropped to 27 lbs. Not a huge improvement, but I'm more interested in smooth pumping and not having to worry about the brass bushings wearing out. Time will tell if the bearings will outlast the brass bushings.

Slavia · Moderator

Some would say you can take a project too far. Phooey to them. Very nice!

lampy · Veteran Member

Sometimes you take a project to far then end up going back to where you started Mad

I spent some time shooting tonight, I heard a few unfamiliar pops and pings while pumping. Then I noticed the pump handle falling away from the pump tube after firing. I felt some play in the linkage at the piston end of the linkage so I pulled the linkage out and found this... the inner race fell out of the bearing when I pulled the linkage apart.

I thought maybe I had damaged the bearing somehow or maybe it was bad to start with. I replaced it with a fresh bearing and tried it again.... about 10 shots in I heard the same ping while pumping and a couple more shots and the pump handle was falling away from the pump tube again.
Looks like I'll be making some bushings to replace the bearings Rolling Eyes

I had my doubts going in if these tiny bearings would hold up, now I know.

Old Lampy · Member

I've seen a couple You Tube videos about the Crosman Vapor Max. Seems a lot like what I was going for a few years back with this build.
It's strange that about a month ago I got interested in this old project again. To bad all the pics have disappeared.

https://www.crosman.com/product/vapor-max/?_gl=1*1c9i6y3*_up*MQ..*_ga*MTA2MzgxNTY3Ni4xNzY0MjE0MDIw*_ga_75X9GP52KK*czE3NjczMjMzOTYkbzQkZzEkdDE3NjczMjMzOTYkajYwJGwwJGgw

AirGunEric · Site Admin

Interesting- and welcome back 'old' Lampy.

Postimage still exists, but I cannot find any explanation why older images are gone...

Old Lampy · Member

It's been a while. I started going through my stash of air rifles a few months ago and have been thinking about finishing up a couple of projects that have been on hold for about a decade.