New guy looking for a rifle. Suffering from analysis paralysis.

Super short version:
I need to upgrade my anti-squirrel device - Benjamin 397, because it is just too loud. I'm considering the Benjamin Akela with an STO moderator. Thoughts?

Super long version:
My 397 is dependable, but it is ridiculously loud for my needs. Currently, I have to brace my rifle against the fridge, fire across the kitchen and out the window to keep the noise inside my house. Before I can do that, I have to look out of various windows to see if any neighbors are outside. Then, if I'm waiting on a shot for too long, I have to go check on neighbors again. Needless to say, I miss my opportunity to fire way too many times.

After reading numerous posts and seeing there's no real consensus on which guns are quietest, I have come to two conclusions;
- a PCP is quieter than a springer
- noise increases as air/propellant increases.

My requirements:

1. Ultra quiet.
I live in a neighborhood with small yards and a lot of retired neighbors outside all the time, including one across the cul-de-sac who feeds squirrels. Most of us have chain-link fences (or no fence at all) so there's no privacy fences to block noise. If they hear a noise, they can easily see in to my yard where I am shooting (this leads to req 2 and 3). If my neighbor sees me killing one of his "babies" I'll get the police called. Without exaggeration, I can hear my neighbor's kid shooting a Nerf gun when my windows are open, so even that is a little on the loud side. Even if I don't see anyone outside, they're old and like it warm, so they have their windows open in the summer a lot.

2. Small (bull pup only)
I need it short. I can't have a gun barrel sticking out of my window. If I am outside and can take a shot, I need it to look as inconspicuous as a rifle can.

3. Kill squirrels DRT, from 5-20 yds. Most between 5-10 yds.
If a squirrel runs in to anyone else's yard and they suspect it was shot, they will let my neighbor who feeds them know, and he will call the police.

4. Needs to be ready to kill something seconds after picking it up and will only be fired dozens of times per year. I have fleeting moments to kill squirrels in my back yard as they pass through. A PCP that can't hold air for months is out. 

5. Air only, no CO2. Personal preference.

Legal considerations:
According to my local PD and Animal Control, it's legal to kill squirrels with traps and pellet guns so long as the pellet stays within my property. However, a neighbor could still call the police for suspicious person with a gun, animal cruelty, improper disposal of an animal, etc. The police can come hassle me, give tickets, or even worse...and who wants that?

My thoughts:
A Weihrauch hw97k would be great for me, but it fails to meet req 1 & 2.
I'm considering getting a Benjamin Akela in .17. It uses less air than .22 and should thus be quieter while still providing plenty of killing power. I could even put a lighter weight hammer spring in to decrease mechanical noise and allow me to turn down the air/power. Hopefully that, with an STO moderator, makes it about as quiet as it gets. I've read about installing a regulator and an SSG to increase accuracy and reduce air usage, but I would likely buy an FX Wildcat before doing all of that.
As for a scope, I have no idea what to look for that will focus to 5 yds and provide 30+ MOA hold over for those close shots. I thought about using a laser for the close shots and the scope for the 10+yd shots. Does anyone do that? Is that a thing?
 
“Most between 5-10 yds” you say.....

Seriously my man you should consider a good set of slingshot. Total silent compared to any air gun you can possibly find and extremely fun as well. A nice shot of 10mm lead ball over 90 grains enough to kill any squirrel while that rats staring at you on a tree. Nothing beats that feel of taking down a pigeon or squirrel at 35 yrds with a slingshot. 
 
If you plan on living there for a while, don't shoot them, -yet. Keep track of them and your property. The second they cause ANY damage call an exterminator and have a record of them being a nuisance. An insurance claim for the exterminator will help too. Then, take the advice about shooting them, given here, and if anyone complains or calls the police, you will be deemed justified and they will be considered unreasonable. Coming to airgun nation and asking about a squirrel problem is like asking a hammer what to do about a nail, and you will get just as myopic an answer.
 
I also shoot pests out of windows. Not because I have to by as stealthy as you but because walking outside almost always causes a pest to run away. Some things to consider.

Having a slightly longer gun is not necessarily a problem as it allows you to sit a bit farther from the window which may be less noticeable to neighbors and more comfortable for you.

Having a slightly longer gun might work better if you're just barely cranking open a casement window.

Having a low scope position can eliminate or at least greatly reduce some of the crazy hold overs required at super close ranges. With your cheek sitting above the barrel height on a bullpup they're not always the ideal choice.

Shooting a projectile slowly can also help reduce some of the holdover as well.

I've stood outside and had my son shoot into the ravine behind us (from inside of the house) so I could hear what others would hear and so the sound of impact was at least off in the distance and not biasing my perception. I'm not sure why but I swear I can hear much more noise from my HW30 shooting than some of my PCPs shooting much faster. I need to do this test again and make sure he's not leaning further out the window or whatever. I'd much prefer to use a springer for pests to avoid regulator creep but my initial tests have me leaning towards staying with PCP.

So with all that said, my current out the window pest rifle is an Edgun Leshiy Classic with a 25 cal barrel shooting Polymags around 460 FPS. I have an STO insert and it's very quiet. Currently the barrel is 250mm but I'm thinking of going to a 350mm barrel so I can be a bit more comfortable shooting out of a window.

It still has a somewhat high scope position but with my high cheekbones it's fairly low and with that 25 cal projective moving so slowly I basically don't have to use any hold over in my yard. 

I barely do any other shooting nowadays so I do have some regulator creep and my Leshiy is not always first shot accurate. Dry firing a few shots before opening the window helps but one doesn't always have time for that. For that reason I am considering setting up my Marauder Pistol (aka P-rod) for the same task. It is unregulated and I gather should be more accurate after sitting for a while, assuming the tank is filled within the sweet spot. I don' t have a moderator on my P-rod but it is quiet for its power level.

Reading this and a similar post I made recently makes me sound like I'm discouraging the use of a bullpup for such shooting and that's not my intention. I've never owned one but if it was what I needed for shooting pests quietly and comfortably I wouldn't hesitate to learn the holdovers.
 
If it's legal as you have stated the pellet must stay on your property. Simply build a bait station with a back stop. Notifying the police and showing them your set up before you ever take the first shot would be a good idea. But after that noise would be a non issue. Be sure to tell anyone who ask you are getting damage from the high numbers your neighbor is feeding. Never admit you like to shoot them. It's because of him you have to shoot them to protect your property. Your just trying to deal with a problem he created.
 
If you insist on killing the squirrels on your smallish property then I can recommend:

-Benjamin Prod tuned at less than 600 FPS with CPHP .22 and a good LDC adapter and LDC

-SPA PP750 or SPA PP700 (both are pistol size, smaller than the Prod) with LDC adapter and LDC

-slingshot works well within 10 yards and is completely silent, needs significant practice to be accurate

Most springers (including the HW97) will be much louder than any of the above.
 
To everyone who mentioned the P-rod, I hadn't even considered a pistol/carbine. It does check off every one of my check boxes and saves me money over the Akela. Here's where the analysis paralysis comes in. If I turned the muzzle velocity down on the Akela to match that of a P-rod, would it be quieter since it has more shroud?


If you plan on living there for a while, don't shoot them, -yet. Keep track of them and your property. The second they cause ANY damage call an exterminator and have a record of them being a nuisance. An insurance claim for the exterminator will help too. Then, take the advice about shooting them, given here, and if anyone complains or calls the police, you will be deemed justified and they will be considered unreasonable.

We're thinking of moving (she would like to move before summer), but this is good CYA info that I will use. With luck, squirrels won't be a problem at our next house. 

I also shoot pests out of windows. Not because I have to by as stealthy as you but because walking outside almost always causes a pest to run away. Some things to consider.

Having a low scope position can eliminate or at least greatly reduce some of the crazy hold overs required at super close ranges. With your cheek sitting above the barrel height on a bullpup they're not always the ideal choice.

My squirrels are so used to people, I will open up my door and throw my yard-work shoes at them to get them to scatter. They don't give a crap because they know of people as a food source and not a threat. After repotting numerous flowers they dug up and sometimes killed, I spent hours cutting out metal chicken wire screens to place in the pots to keep them from digging...but they will still sit ON the flowers and smash them! I have to chase them to get them out of the flower pots. Jerks!

I like the compactness of the bullpup, but a low scope position is out of the question. I would prefer a standard rifle with open sights along with see-thru scope rings, but quality air rifles come without sights and it'll look too much like a "gun" if I am outside with it.

Based on personal experience, my recommendation is the Taipan Vereran. Even with an additional suppressor, it is short, accurate, and very quiet.

Good looking gun in the red laminate stock, but outside my price range.
 
If it's legal as you have stated the pellet must stay on your property. Simply build a bait station with a back stop. Notifying the police and showing them your set up before you ever take the first shot would be a good idea. But after that noise would be a non issue. Be sure to tell anyone who ask you are getting damage from the high numbers your neighbor is feeding. Never admit you like to shoot them. It's because of him you have to shoot them to protect your property. Your just trying to deal with a problem he created.

I put peanuts at the base of a large tree or on my deck railing in front of the tree. I use that method for most of the squirrels I shoot. The problem is my neighbors can't know I am killing squirrels. The one that feeds them, they are his "babies". He never had kids, so for decades (yes he's old and retired) he's been feeding critters at his house and considers them his kids. We talk often and he will interrupt our conversation to say hi to his squirrels, addressing them by name. If anyone finds out, they will tell him (they've all lived in this neighborhood for 30+ years) and they'll all hate me.

If it wasn't for my garden hobby and our other plants, I wouldn't even be killing them since I am not eating them...but they just dig up and destroy all of our plants. This is the first year we were able to grow much of any produce and it's likely because I killed 40-50 this summer between traps and shooting. Last week we sold over $300 of produce.

Why not just get a moderator? I know I'm not going along with the enablers but it would be way cheaper. If you get a pcp you'll have to get in the very least a hand pump.

That's a fair and reasonable question. I would like to, but my 397 just doesn't shoot like it used to. I used to shoot old shot gun shells off logs when I was 20 yrs younger, but now it's doing 7/8"-1" 5-shot groups at 13 yds. That's with 7.9g Crosman HP and the plastic tipped pellets (I forget the name). I can't make headshots confidently beyond 10 yds otherwise I would look in to silencing the gun I already have.

If you insist on killing the squirrels on your smallish property then I can recommend:

-Benjamin Prod tuned at less than 600 FPS with CPHP .22 and a good LDC adapter and LDC

-SPA PP750 or SPA PP700 (both are pistol size, smaller than the Prod) with LDC adapter and LDC

-slingshot works well within 10 yards and is completely silent, needs significant practice to be accurate

Most springers (including the HW97) will be much louder than any of the above.

Don't really want to, but they just cause so much damage. I've been using traps, but apparently the wrong ones. I am still looking for right trap/bait combo. I'll look at those pistol options you mentioned.