Air Arms S510 XS Stealth Carbine PCP Air Rifle

Every single thing! It's beauty and balance are just for starters. This rifle is almost silent. The pellet hitting the target is louder than the shot...by a lot. I ordered it with a Leapers UTG 9x40 scope and purchased the 20 for 20 service and am so glad I did! Out of the case this rifle was right on the bullseye every time (or should have been but missing was my fault). Lastly, the craftsmanship that Air Arms put into this is incredible. I like everything about it.

Nothing.

Yes, it is a pricey rifle but you get what you pay for, and, in this case it's worth the money.

This rifle is well balanced, although feels heavier overall than the weight listed. I selected a .177 since I already own PCP's in the other calibers. The FPS using 10.3's on the highest setting averaged around 990. Faster than I expected and nice to know I have room to adjust based on the speed and shot count I want to achieve. Accuracy surprised me at the original speed tested, averaged around 3/8" groups at 50 yards. Based on my experience, with the correct pellet and good scope you should be able to keep all pellets touching at 30 yards. This gun is quiet in comparison to a shrouded barrel and slightly quieter than some others with factory moderators. Cocking effort is smooth with minimal effort required. 1st stage of trigger as preset from the factory is extremely long with very little resistance, 2nd stage just a hair heavier than what I prefer. I have not yet made any trigger adjustments, so not sure how it will dial in after adjustments.

The magazine sits low enough to accommodate scope mounting without having to use higher rings. Although this part of the magazine design is good, I think the location/size of the O ring could be redesigned to create enough resistance to the pellets when loaded to prevent them from falling out. After the magazine is loaded, the cover prevents (9) of them from falling out, but the last one has an open hole and can easily fall out prior to or during the loading process (inserting the magazine into the breech). I end up rotating the cover so it is in-between two pellets while storing the magazines. The magazines are also a bit tight when inserting them into the gun which will most likely be reduced with use. Other than these minor items, other features like not having the magazines spring loaded and the recent revision to the indexing system are big pluses. Please also keep in mind I am comparing the trigger to other very high quality pellet rifles which cost more on average.

If you are looking to purchase something in this price range, my comparison based on other rifles is as follows: Daystate Huntsman Regal - maybe a bit lighter, better trigger out of the box, accuracy and quality appear to be comparable, magazines double the price. The Air Arms has smoother cocking (lever vs. bolt), is quieter and has a better shot count. Original FX Streamline - lighter and better trigger out of the box, good shot count and accurate, expensive magazines. Air Arms a bit quieter, stock fit and fore end would be better with someone with larger build/hands. Weirauch HW 100 - Nice magazine system, better trigger out of the box, well built and accurate. Air Arms would be lighter, more attractive bluing, better shot count and most would find the overall gun better looking and not as bulky. I have actively used all of the above and various other makes and models and I was a bit skeptically if I would be satisfied with the accuracy of the Air Arm. I am very pleased,

Very quiet and very accurate. Lovely to look at. High shot count.

The Air Arms fill adapter. For some reason, mine won't seal, so I have to send the gun back because I can't get air into it.

I had to think a bit before this review. I don't want to say every one has a problem because mine does. The gun is great. Quiet, accurate enough for shooting bottle caps at 45 yards. Can't go wrong with this one. I've just had a bad experience with the fill adapter.