Just restored a few old (50's & 60's) sheridans and benjamins with parts from Bryan & Assoc.- gotta give a shout out to them there for having good advice and the right part at the right time.. but anyway, I re-sealed a crosman 180 Co2 rifle and am having a little problem. the gun finally holds Co2, but when I fire it it sputters, releasing about 8 shots worth of Co2 on the first 3 shots. So far I get 1 so-so shot out of an 8oz co2 the rest are underpowered so that I can see the pellet going through the air. after ~4-5 shots the co2 is so low the pellet doesn't even leave the barrel. Any 180 owners out there who can offer any advice on correcting this?

Between the lower pressure tube and the breech is a transfer port seal that allows the gas to get from the valve to the barrel without escaping to the outside. It looks like a short piece of plastic or metal tubing, maybe 1/4" in diameter. What happening is that small port seal is not working properly, and its allowing gas to travel between the outer wall of the valve body and the inner wall of the tube, and entering the space behind the valve where the hammer is. When you fire the gun, this escaping gas from the initial shot drives the hammer back, and a second less powerful hammer strike occurs. This repeats until not enough gas is released to move the hammer. So what you get is like a short quick burst of several shots, sort of like a machinegun burst.
Oh, by the way, the 180 uses 12g, not 8 g powerlets. If you're using 8g carts thats another problem.

 Thanks Dave!

 I shoulda thought about referring this'un back to you!

 Those old 180's are sure suprises the first time ya touch one off in .22 caliber. You expect MUCH less of a Muzzle Blast, and then when that big'ol pellet gets to it's mark, in the works another suprise, that BIG IMPACT!!!

 *Please note the pictured "Hunting" ammo I last used in mine for  my LAST kill ever, (a large Female Ground Squirrel). She was literally picked up off her feet, dead before hitting the ground, with one of the old vintage 16+ gr "Super Pells" from 23 yards out! Yes, it takes some "sorting" to find good ones from the Lot, but they are definatelly flying Garbage cans!

Thanks for helpin!

 ZVP

wertq,

 My 180 did the same thing, plus vented a slo leak out the bbl. It was all origonal so I figgured why not send it to Tim @ Mac-1?

 He did a total rebuild, a Power Mod, and when I finally tested it (Temps in the mid-70's), it leaked out the bbl still...

 I contacted him, and he suggested heting the valve area with a HOT hairdryer (supposedlly the Valve seal Material he uses is very hard and needs to form-in?), or he said to send it back for re-re-build.

  Conditions havd delayed my sending her back yet, but I think Tim'll be good for it!

 As to the rapid-fire gas thing? I think that is just the old Hammer Spring being weaker than the valve stem spring. It apparentlly "jackhammers" when it gets tired???

 BTW, That Mac-1 180 Power Rebuild is a real MONSTER! When my 180 first fires (1-2 quick shots, before all the Gas dribbles out...), the power rivals my that of my .22 Webley Stingray Carbine! I'm not really a big CO2 rifle fan, but the 180 came from an old friend and is very dear to me. Now when I get this Mod repaired, it's going to be quite a blaster too!

 ZVP

 

thanks for the replies. I will check the gun out again later this week when I have more time and let you know what becomes of it. It's been a good week, just got an old late 50's sheridan blue streak .20 back up and shooting as well as an early 60's benjamin 300 .177. The only troublesome one of the bunch was that 180. Normally I go for spring piston dianas too, but these were guns I "inherited" and it just kills me to see them sitting collecting dust because the seals are all shot. Still have 1 pistol to restore from my great grandfather, a sheridan that was my grandfather's from the 30's and 2 more that are my dad's. The stable is getting pretty full

That ones not as old as you have guessed since the first ones didn't appear until 1947 when the Supergrades were introduced.

How can I post a pic? Just took a picture of part of the "stable".. would love to show em off Also the real old (1930's) one is a benjamin. The sheridan is from the 50's.....

Use the "insert object" button below the response dialog box. When the Web Page Dialog box appears, Click "Temporary Files" in the left pane. Then click on "upload" under the left pane. In the "upload new file" window that appears in the left pane, click the "browse" button. This will allow you to navigate to your picture files on your hard drive. Click on the picture you want to upload. The "upload new file" window will reappear. Click "upload". When the file is finished uploading, the picture will appear in the right pane. Click "insert image" below the left pane to post the picture.
Make sure the file is either a .jpg, .png or .gif filetype or it won't upload. Filenames need to be short, 8 or less alpha-numeric charachters, no spaces, symbols, punctuation etc. File size needs to be under 100k. The best way to judge if the picture is too large is by pixel count. For most monitors, 800x600 pixels is about as large as you want to get or you'll have to scroll around to see the entire picture. Large pictures also tend to send the text of the entire thread off the screen so scrolling sideways is neccessary to read it.
There is a storage limit, and pics can't be deleted. They last for 7 days(theoretically) and go away.

Theres other ways to do it, but this is whats provided by NW54.

hate to be a techno-retard, but there is no "insert object" button when I reply to your message. Do I reply to my own? or..?

you must be using firefox or some other browser that isn't compatabile with NW54 posting protocols. Thats why you can't see the insert object button. Best bet is use Photobucket.com. Open a free hosting account and upload your pics. Under the thumbnail pictures that appear on Photobucket is the url of the picture Copy and paste the url into the message box. That should enable you to post pictures.

One easy thing to check is proper seal in the transfer port tubing referred to in Dave's message. While firing the 180 carbine in a safe direction, place one hand over the closed breech/bolt. If you feel a blast of gas excaping, its likely the transfer port tubing needs replacement. If this is the case, it is easy to get at. You can purchase 1/4 inch vinyl tubing at a hardware store. The piece you will need is only about 1/8 inch long, but trial and error will be required to obtain precisely the correct length. Its amazing that this arrangement is the best crosman's engineers could come up with.

The 180 is a great shooting gun. Quite accurate with respectable power. Good luck

Fred

you hit it on the head.. seal problems. I placed the seals in the wrong place. First one was in the groove on the co2 valve body (towards the front end of the gun.. the second one, that was missing when I disassembled the gun (wonder who did that??) was the seal that goes at the back of the valve body near the valve plunger (that the hammer strikes when the gun is fired) I had used that 0 ring as a replacement seal on the co2 end cap because that was the only other 0 ring in this gun in the condition I recieved it in. So back went the original 0 ring onto the co2 cap and now shes a mighty fine shooter! Just shot it a little this morning but it looks like a nice little gun. No idea who may have disassembled it before me but obviously they left a ring out, which explains why the thing always hung on the wall at my (long deceased) great grandmothers house for as far back as I am old enough to remember.

Thanks for the tips.. woulda been a long time fixin without everyone's help. I never suspected a ring went on both ends of the valve body either, since I couldn't see it in any of the exploded drawings and the thing seemed to have a rather queer, not-so-straightforward design in the first place anyway (for example that pastic exhaust/gas transfer bushing beween the lower tube and the barrel.... why, crosman engineers,why??...)