Some Notes On Reassembling the Crosman 500

So the handle on the BB magazine follower broke off when I was futzing with the gun.

So I drilled and reamed.

And pressed a 1/16” dowel pin in with a drop of superglue.

It works. I might shrink some small diameter heat shrink on it, not sure.

I made a seal for the valve, cleaned and reassembled the valve.

The biggest problem was that the barrel shroud wasn’t lining up correctly with this boss that’s part of the frame casting.

And the boss is somewhat mushed from having the shroud forced against it by the previous owner.

With the barrel and BB magazine inserted into the valve I found that the barrel wasn’t going in to the same depth as the magazine.

As you can see here. The muzzle cap has two holes of the same depth so I assume they should be the same.

The culprit seems to be that the barrel end is flared. I don’t know if that was done by the factory or by the owner. I suspect the barrel isn’t original. In any case it has to go.

So I inserted a transfer punch that was a slip fit and hammered out the dent.

And trued up the end, so that now the barrel and magazine are the same length.

And the shroud magically fits over the boss in the casting (I cleaned it up with files as well.)

The hammer spring (?) position was completely wrong when I disassembled the gun. This tells me that at least one person definitely was in here monkeying. It also shows why you need to take lots of digital pictures when you disassemble airguns. Through trial and error I found this is probably the correct position.

I’m not sure why the spring has that bent leg.

One more view for the sake of all who delve into these things.

The forestock was missing the square nut and screw. I used a #10-32 which isn’t original but I don’t really care. It works.

After reassembly I found the trigger was sticking – you can see scuff marks where it was binding against the slot in the receiver. So I massaged it to where it doesn’t bind and lubed a bit more.

The rifle works! It is actually fun to shoot and not as inaccurate as some BB guns. Semi auto can plinking is a treat.

Crosman Powermatic 500 Disassembly, Part 3

On I go…

The barrel and magazine just popped out. I’m not sure whether that’s a good or a bad thing. The barrels seems to have been bulged to be a press fit in the valve assembly.

Did I mention it was rusty?

The roll pin that holds the front sight and barrel plug thingy in.

I punched out the pin.

And gently tapped the piece out using a chopstick as a drift. Bamboo chopsticks are wonderful tools.
It was difficult to slide the barrel out – The shroud was dented so I had to massage it with some pliers.

This die cast part is formed around the barrel. It allows the sight to be screwed in as well as helping align things.

There’s a notch for the magazine to pass through.

No seriously, it’s rusty.

I removed the piercing pin retaining nut.

All the piercing parts. Looks like another Crosman 38 style assembly.

The leftmost washer was stepped on the underside.

The valve stem is rusty…

The seal is completely gone.

The BB shuttle?I’m guessing this is actuated by that flat piece in the left side of the action.

The shuttle.

That plastic piece covers the magnet (presumably for BB feeding).

You can see bits of steel fuzz on it.
So now I have to clean the damn thing and see if I can even get it to cycle, much less work. Not particularly optimistic given my failures of late. But we’ll see.

Crosman Powermatic 500 Disassembly, Part 2

On I go…

I removed the CO2 clamp & screw.

One screw on the other receiver half.

Notice how corroded the screw is…

This freed up the valve assembly. One spring was unhooked.

The valve assembly with barrel and magazine attached.

It’s important to take pictures of how spring hooks are oriented.

Everything is rusty.

The trigger group.

It’s somewhat interesting and different.

This piece pivots on that pin.

Let’s take more pictures. It will help.

You know it hasn’t been shot when it has cobwebs.

The grease has dried out completely.

I punched out the one, longer, pin.

Interesting spacers.

I tried to remove the shorter pin but it seems swaged – best to leave it. I can clean around it.
More to come…