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@Frog4aday What are the downsides of a PCP? Can I get an air dryer, or some other accessory that will extend the life of the rifle?
TheRifleMan556 nailed it in his post above. The moisture needs to stay out. There are ways. If you were going to go whole hog and jump both feet into the 'air-rifle' game, then perhaps a PCP is the way to go, especially if you lived somewhere DRY, like the rocky mountains (low, low humidity.)
But if you really just want to nail some of the rabbits eating up your yard, a QUALITY spring-piston airgun will get 'er done with fewer hassles and less money. The air rifle I've had since 1982 was sold as the BEEMAN WEBLEY VULCAN, which I only see shown now as the "Webley Vulcan", but I can say with certainty it is accurate and has lasted all this time with no problems (knock on wood!) Just a drop of airgun oil down the piston tube now and again and it just keeps going and going.
Get a 'name brand' gun (Beeman, Diana, RWS, etc.) and it will shoot and last. I'm not sure how the Spanish guns hold up (Gamo) but others will chime in, I'm sure.
My personal opinion is that putting a SCOPE on a "springer" is a waste of time. An exercise in futility. Just use the open sights. It will be so much simpler and less frustrating in the long run. Springers do weird things to scopes, rings, and mounts. When you talk about a springer shooting a 10" group at thirty yards, something is seriously not right! And I'd bet it was the scope (or mount, or rings, or all of that.) Shoot a quality one with the open sights and it'll surprise you how well they can shoot. With my springer, I couldn't get rings to hold onto the mount. And scopes came apart internally in short order. The one scope that 'lived' would slowly slide it's way down the mount with each shot. Such a pain in the a-s-s, I eventually just gave up and stuck with the open sights which work great for the effective distance of the gun (40 yards or so is my comfort zone on 'big' stuff like squirrels and rabbits.)
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This was a good quote on the 'pros' of springers from this webpage (
https://www.topairgun.com/spring-piston-air-rifles):
High powered spring piston air rifles are the best guns for long range adult targets shooting, hunting small game and controlling pests. Spring loaded pellet guns are self contained and always ready to go. All you have to do is cock it setting the spring activated piston, load a pellet, take aim and pull the trigger. With a spring piston air gun, there is no need to carry around an air tank or cartridges that can run out causing your pellets to lose power and accuracy. And you don't have to worry about carrying around extra tanks. Spring loaded pellet rifles are extremely consistent and accurate. The spring piston has the same amount of force with each load so the pellets travel accurately and at the same high powered velocity with every shot.
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I have absolutely NOTHING against the PCP guns! They are great. But when you have to deal with air tanks, moisture issues, refill tanks, 'pumps', and so forth, they start to be more work. You want to see a rabbit in your yard, grab the gun, load a pellet and shoot it. A springer makes that easy. I had mine sitting by the back door with a pellet already loaded in the chamber. All I had to do was cock the barrel, aim, and shoot. That's it. And then it got put in the corner again. No valves or air tank to deal with. No 'pumping it up' again after it sat for too long. No air to leak out over time.
The 'downers' to springers is they are louder (staple gun, nail gun loud), they 'recoil' a bit, and they don't do well with scopes on them. There's no free lunches. You gotta pick what's best for your needs and accept the cons with the pros.