pcp for 8 yr. old boy?

PCP…Nope

Side lever from Russia.

Adjustable length of pull..

You can find them and PA sells one similar..



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I bought a talon p frame and a 20 cal barrel for my daughter who was 8 at the time. It worked perfectly. Not only can you adjust length of pull but you can change the top hat and hammer spring to make it as weak or powerful as you want. I highly recommend it. Also a single shot is safer for kids IMO. I'm getting almost regulator consistent strings by putting an oring behind the top hat.

I'll second the TalonP. AirForce guns are a very flexible platform. You can make them fit almost any need.

Also, I am a huge fan of single shots. Not only safer, but teaches a new shooter to take their time and make each shot count.
 
Yep and 20 cal is perfect for birds, rabbit and squirrel. I'm a little squeamish about handing her a 25 but anything below that I'd be happy with. I went with the 20 because airforce has a good price barrel at that caliber. It's really a good middle ground if 177 is too light at 22 is too heavy. You can put a 14.3g pellet in the 20 and have better bc than a 22 as well. Very hard hitting and flat shooting option. 
 
Sounds like when I got my wife a drill press for Christmas

Ha Ha! I bought my daughter a drill press and clamps for Christmas, her husband bought her a bandsaw. Now she wants a tablesaw and thickness planer for her birthday.

I would look into getting a SawStop for her. I have a 5 hp Cabinet saw and am lucky that I still have my right thumb from an incident a few years ago and I’m typically very careful. Sorry for the woodworking safety discussion...back to airgun talk.

I would also recommend a Weihrauch springer. You can pick a new one up from Krale for an extremely reasonable price. If you do go the PCP route there are a BUNCH of rifles that would be fine and several have already mentioned some good recommendations. 
 
FX dream Tac w/ short barrel , little tube & AR adjustable stock. He can grow into it & u can use it too. I think you can remove the folding thingy to make LOP shorter & gun lighter. Plus you can adjust the power way down. W/O the power plenum. Use the short one. I need to see how small I can make mine for my grandkids. 

FX Dream-Tac Compact | Utah Airguns
 
I bought a Kral NP02 off the classifieds here about a year back. I swapped the bottle for a .25 liter and trimmed the sleeve down on the stock so I could shorten the length of pull. I believe it’s the perfect pcp setup for a young boy. I’ve got three boys under the age of ten, I’ve put some real thought into the subject. my oldest two are big for their age, but my six year old shoots it good too. I also have a NP03. They do great with it too, but you do a lot of filling with a new shooter. The rear bottle makes the gun handle better for them too.

Edit: It’s my oldest boy’s gun. He’s 9 and has killed quite a few critters with it.