That's one very nice looking pistol. I know the sentimental value makes it priceless, but I got curious and looked it up at the Bluebook of Airgun Values and got this. I know it doesn't help answer your question but thought I'd throw it in:MODEL 79G- .177 cal., CO2, SS, styled after S&W Model 41 semi-automatic pistol, gun blue finish, brown plastic grips, 8.5 in. barrel, 475 FPS, fully adj. sight, 42 oz. Mfg. 1971-80.View Historic PricesGrading 100% 95% 90% 80% 60% 40% 20% $175 $150 $125 $100 $75 $50 $35Last MSR was $53.45.Add 50% for orig. box with can of S&W pellets and box of CO2 cylinders.Add 30% for orig. box with plastic envelope of pellets and CO2 cylinders.Add 25% for early pistols with adj. trigger.
There's a disassembly guide here:Link removed because I'm not allowed to post external links! Must be a newbie thing!You can find other blogs with modification tips by Goggling "s&w 78g 79g blog".Also, there was a previous thread on this forum that may help:http://www.gatewaytoairguns.org/GTA/index.php?topic=54347.0
I rebuilt my 78G on the couch, as long as nothing is corroded it should come apart fairly easy, I was intimidated at first reading the posts about it but it wasn't all that bad.
Paul,One thing that you can do to help ensure you get it back together correctly is to take pictures at each step of the disassembly, and set the parts aside in the order that they come off. Have the disassembly blog up on the computer too, and try to do it when you have enough time to complete the job without interruption. You'll do fine, I've done a couple of these and it isn't that difficult.Hoppes should be just fine, but be careful about getting strong solvents on the painted areas or plastic grips. Get some Pellgun oil so that you can put a small drop on the tip of every other CO2 cartridge, and lightly oil the internal steel parts as you would any firearm.You'll be impressed with the power and accuracy of the S&W 79G, they're a lot of fun to shoot.
It's been a while since I had one of these opened up, but I'd imagine that the "freezer tube" mod would work. Just get a short length of the plastic tubing that's used to connect refrigerator ice-makers, and cut off a piece that's the same height as the transfer port button, then replace that metal button with the piece of plastic tubing. The plastic will get a better seal than the metal-on-metal of the transfer port button.
Paul,That looks in incredible shape and to top it off it has sentimental value! A keeper for sure!Coincidentally, I just resealed one this week. Did you get the reseal kit from MAC1 with the new poppet? Great kit. So here's my advice...1) Get the kit from MAC1 with the poppet2) When replacing the tiny orings on the exhaust valve first get the hottest tap water you can and drop those little suckers in there for a few minutes. It makes getting them on much easier.3) place a tissue over the loading port and shoot. This will tell you if you have a transfer port leak.4) if you do have a TP leak first check that the barrel has not twisted on you. It can easily and then you won't get a good seal.5) depending on the shape of your TP you might want to cut a new one from some ice maker poly tubing6) if it all seals up and you have low power, check the power adjuster. Yeah, I didn't know this and was wondering what was up. The threaded screw in the front of the barrel adjusts the power. Note that there is also a screw inside the adjuster. That should do it. It is a pretty easy reseal job and only takes a few minutes. Andy
For the record, I got the same kit off of ebay and it's been holding for a long time, even holds CO2 for a couple weeks at least... I haven't shot mine in a while though