Barrel length vs power in a springer

[ChaoSS]

You don't need to go into more detail, it's probably more work than I'm interested in doing, on a gun that might not be able to be done without spending tons of money.

I'm shooting an Umarex Octane, and would not mind it being somewhat quieter. Actually, it's probably still dieseling, so it's probably still making more noise than it will when it's fully broken in.

I'm thinking next year I'll get into a PCP, and then, at that point, I'll want to discuss, with you, or someone else knowledgeable, the Air Force systems vs the Marauder, but that is a ways away, and by then, who knows, there might be something else worth getting into.

 

[Chevota]

The Umarex Octane is like a Ruger Air Mag with a nitro and different trim is it not?
It could be dieseling, but if it's .177 then I'd say it might be the pellets going ss. A 10.5gr pellet will probably fix that, if not a heavier one like the JSB 13.4gr will. Aside from eliminating the ss crack, the 13gr pellet should quiet the gun down some and tame the reverse recoil/shock. Otherwise there's not much you can do to quiet it, little stuff like button the piston, maybe some kind of dampener in the stock. Making a longer suppressor is risking prison time, but you might be able to make the one on there work better, but like you said; probably too much work. However it wouldn't be expensive because I specialize in home brew mods that are cheap or free, the only expensive parts I buy are things I can't make like barrels $15, stocks $22 and such.
If you ever take it apart I'd love to see the internals. The original setup like the Ruger could not accept a nitro as it was, so a piston and trigger change would be needed and I'm curious how they went about it. From the pix it looks a lot like a Gamo trigger.

 

[RussB]

My 2 Weihrauch springers were all made quieter after tuning them. The firing cycle is more of a "thump" than a "twang". The judicious use of spring tar really dampens the action.

I also have a tuned RX (adjustable gas piston) which is still quite loud for a "springer". It's firing cycle is louder than a 22 rifle with CCI CB's

 

[ChaoSS]

The Umarex Octane is like a Ruger Air Mag with a nitro and different trim is it not?
It could be dieseling, but if it's .177 then I'd say it might be the pellets going ss. A 10.5gr pellet will probably fix that, if not a heavier one like the JSB 13.4gr will. Aside from eliminating the ss crack, the 13gr pellet should quiet the gun down some and tame the reverse recoil/shock. Otherwise there's not much you can do to quiet it, little stuff like button the piston, maybe some kind of dampener in the stock. Making a longer suppressor is risking prison time, but you might be able to make the one on there work better, but like you said; probably too much work. However it wouldn't be expensive because I specialize in home brew mods that are cheap or free, the only expensive parts I buy are things I can't make like barrels $15, stocks $22 and such.
If you ever take it apart I'd love to see the internals. The original setup like the Ruger could not accept a nitro as it was, so a piston and trigger change would be needed and I'm curious how they went about it. From the pix it looks a lot like a Gamo trigger.

From what I understand, yes, it is the NP version of the Ruger Air Magnum. Different stock. I like this stock, although some people seem to think it's ugly.

I've fired it very little, so it's definitely still dieseling. The PA blog says that this one takes awhile to quiet down. This weekend I want to take it to the gun range and run a couple hundred pellets through it, if I can, and see how quiet it gets. I really want it to be quiet enough to shoot in my yard without the neighbors hearing and calling the cops. If that's not going to happen, then oh well.

And this is the .22, and the lightest pellet I have is the 14.3 CPHP, so the dieseling is doing something amazing, it isn't going SS. It doesn't sound like that anyway. One of these days I may take it apart, and if I do, I'll take pictures for you. That won't likely be any time soon though, I'm not much of a tinkerer. I do what I need to do when I need to do something, but I don't particularly enjoy it so I don't do it just because, or just to experiment.

I have heard the trigger compared to the Gamo one, though, and I don't know if that's good or bad.

FWIW, when I shot it just outside my door, to me it sounded like a lot of mechanical noise, my wife inside said it sounded like a gun shot, just quieter. I'm hoping that means that most of the noise that carries is the air blast, which should go down as I shoot it more.

 

[Chevota]

Russ: I recently sold an RX I had for about 12 years. Amazing quality, too nice actually because I rarely risked taking it outside for fear of scratching it. It's the only gun I didn't tune because I didn't want to mark up the screw heads or anything. Anal I know, which is why I sold it.
I usually use disposable guns like Crosman so there's little fear of damage or confiscation. I use tar too, but I prefer to use another method to dampen the spring by using a plastic sheath, and if possible a silicone plug. It isn't as quiet as tar, but you don't lose power and there's no mess. No matter how careful I am I usually end up getting tar on things I wish I hadn't.

Chaoss: Oic. Well, JSB 18gr and H&N Barracuda can help tame a .22 if you want to try them. I can't speak for the mechanical noise because the nitro guns I've had, mostly Crosman, were very quiet mechanically. Tightening everything and buttoning the piston is where I'd probably start on yours. If nothing is loose then it should be a nice solid thok like a rubber mallet on concrete. The way I deal with dieseling is I have an old towel rolled up tight like the shape of a small bread loaf with a band of duct tape to keep it together, then with the barrel touching one end I pump pellets into it until the loud dieseling stops. Hard to say how many shots because it depends on the amount of grease they stuffed inside, but usually it's only 5 or less loud shots. I can't imagine it taking more than 20. The quiet "smoke only" shots will take much longer to stop, maybe even 100. The same towel is also the backstop for targets or Crony use indoors, it's a great pellet trap imo; cheap, silent, and never fails.
The Gamo/Crosman/Stoeger/etc trigger is considered horrible by most, but the majority of that is because they have a heavy spring and limit adjustment, both of which I'm sure is to prevent lawsuits. With a trigger job it performs great, and there are quite a few ways to make it better from a simple screw change that takes 30 seconds, to an hour or so of work which nets the best possible result.