Paintball

[Railgun]

Got started on the rebuild and tuning of my used but new to me SB last night. First step is cleaning all the parts. And since the body is what they all have to go into I started with that.

A little more polishing with the "deep cleaning" car wax to bring out a little more shine and it'll be done. I used 600 grit wetordry to clean and smoothen out some scuffs and scratches then 1000 followed by 2000 to smoothen and cut out the scratches from the 600. Final buffing is being done using Eagle brand Wet1 car wax that has a fine polishing compound in it. A little wax and heavy pressure to cut the brass and it's coming up like a mirror.

Next is what to do about the bolt. The upper side looks like some was hacking at it with an adze! There must be a strong electrolytic reaction between the brass and aluminium. I'm not sure but right now I'm thinking of a plastic replacement since a lot of metal is just gone. I'll clean it up and post a pic for the comments of others that are more knowledgable than me.

So here's the body.....

[Ir0nExpress]

It's pretty! :O

[Phantom Power]

Yeah, the sheridan bolts do have a tendancy to pit and dissolve if left in a gunky state for too long. The anodizing on them wears through in parts because of the pump stroke and then the raw aluminum is exposed.

If you make yourself up a delrin bolt then you'll have a smoother pump stroke too Oh, and by the way, what is the thread pitch of the sheridan valve nubbin ?

[Railgun]

It's a real oddball. It's 32 TPI but it's larger than 1/4 but smaller than 9/32. Neither is it tapered so it's not something like 1/16 NPT. It's within a couple of thou of being 7mm's but the thread pitch doesn't match to any standard metric thread spacing. So I've come to the conclusion that it's just a Sheridan Valve Thread or SVT and nothing matches.

Sort of harkens back to the 17th and 18th century when there were no standards for threading and every company and local machinist had their own "standards".

[TREYisRAD]

looks good

[Railgun]

She's back together for the moment again. Mods to date are;

• Cleaned up and polished outside of body. Also cleaned and lightly polished inside of barrel and bolt area to minimize any effects of a few deeper scratches I found in the upper bore.
• A new UHMW PVC black bolt to replace the paint electrolisized stock bolt.
• Stainless steel pump rod to replace the rusted stocker. All polised up to a T to match the shine of the body.
• Pump handle inner surface and upper lips have been coated with mylar self stick stock called Fascal to try to limit any scratching of the brass. As a bonus it all but filled in the slop in the stock handle.

Between the plasic bolt slicked up with a little Dow33 and the mylar slip sheet on the pump handle and the polished hammer all lubed up this is one of the smoothest pumps to cock that I've now got. As much as I don't like the metal pump handle it does make it super easy to lightly "slam" cock the thing. Almost any speed in the pump at all and it drives that hammer back.

Upcoming mods now that I know my present work is good to go;

• Modify an autococker slider frame to use on the SB.
• That will allow hookng up a bottom mounted ASA for a 3.5 oz bottle or a CCM bucket changer. This will be mounted Island style.
• Loose the back block and feed the CO2 directly into the side port via a microline fitting adapted to mount with one of the original banjo bolts or some new setup that allows this feed method.
• A new back block with an adjustable spring preload to allow the possibility of velocity tuning with an allen key instead of breaking half the gun down to shim or swap springs.
• Loose the pump handle in favour of a toggle or box handle on the back of the bolt. Either way it will still slide to use the locking balls. Another option that I'll look at will be a figure 8 inside but inverted U shape outside hollow shell that mounts to the bolt and extends forward over the tubes. The outside being fluted much like the back of a Colt .45. Think of it sort of looking like a duckslide but at the rear and on top. Not sure which I want. Or perhaps just make both! So it'll be rear cocking in any event.
  
  Here she is for now. But not for long.