That piston liner is kind of a pita so the first one might not work. Once you get one done I think you'll have the hang of it. Ideally you want it to be a press fit which both makes it tight and keeps it perfectly round. Whatever plastic you find won't be the perfect thickness, but anything is way better than what it was. If you have a smaller Canadian spring then you might have room for two layers of 2-liter bottle, but you can always make a shim liner out of something, maybe a long beer can? Basically like that pix of the oem 350's steel liner, then put your tight fit plastic layer in that. I've made them with just one 2-liter bottle which leaves up to .030" clearance and it works great, so no worries getting it perfect, but if you have time I'd try to make that closer to .010. I'd also sand the OD of the spring smooth so it can't scratch up the liner and skims over it easily. The guide should explain everything well enough but I always forget stuff. If you have Q's feel free to ask. I suppose you could goop the moly paste on the spring guide since that will be the main source of noise after the liner is in, and since that's the less dramatic end I think the moly will stay, or at least stay longer and it should not affect power enough to notice. The main reason things like paste and sticky grease, sticky silicone etc affect power is because when it's in the compression tube the seal and piston have to plow thru it, plus a section of the piston skirt is no doubt dragging thru it too. The spring is struggling to get the piston going as fast as possible to make max pressure, and already falling short, but now think about all that surface area covered in grease. Picture wiping a squeegee firmly across a greased surface 3" wide x 4" long. Slow no prob, but as fast as possible and it's an issue. The thickness and especially stickiness of the lube and its temp make a difference.... This is why you hear about cold weather costing you power. So do it right and power should max out and cold should have little effect. Tar will likely never make it to the compression chamber, but no worries of detonation if it did since it would so little. The real worry would be having it on the tube wall to slow the piston. Tar generally stays put because it's so sticky, picture sticky like honey but much thicker than peanut butter. You only put it on the spring so it should never get on the comp tube, but it is on the spring and the spring slides past the guide and inside the piston so that's where you get the power loss. If carefully placed and the other parts are dry lubed then coated with a very thin coat of motor oil or grease then it should allow the tar to slip past w/o sticking. This is another cool thing about the liner since it's easy to dry lube, then oiled it's pretty much tar repellent. The main reason I dislike tar is it's so messy and if you ever take the gun apart again it's an ugly mess to get off. It's not like you can wash it off with soap and water. As far as I know it is a type of grease, not tar like road tar. It may look and act like tar, but upon closer inspection and smell it clearly isn't and smells like grease. No fumes either. If I were to rate its stickiness, with 0wt motor oil being a 1, sticky grease a 2, then tar is a 5. If you do the plastic liner you should be pretty happy about how much it quiets it, but options to make it even quieter include a tighter fitting liner, the silicone plug, thick grease or paste on the guide and spring, and as a last resort; tar. If you use tar you need to strip the spring squeaky clean so it can stick to it, if it's oily then the tar might sling off. And don't get it on anything you don't want it on, like clothing, carpet etc, because your options for complete removal are pretty much nil. The clear tar is a bad idea because it's silicone, but also because you can't see it and end up spreading it around the house. The tungsten should be in powder form, and rub it directly into the metal or whatever. Details are in the guide I sent. If you get spray then how do you mix it with oil/grease? If paste then what is the paste part and what if you need it thinned way down like oil for the comp chamber or pivot points? Powder is cheapest and the way to go. I have air brushed moly on auto parts, but that was for a much thicker layer and I assume it had something in it to hold it together. If you were to air brush/blast tungsten powder you'd no doubt lose the vast majority of it and still not do a better job than rubbing it in by hand. Picture rubbing pencil lead into paper until it's a shiny dark grey, that's what a tungsten'd part looks like. Ultra thin layer but amazing. You could use pencil lead too I suppose, I have a pound of graphite powder that I use for less important things. And a pound of motor mica for virtually mess free dry lubing.
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