If you went to the springer forum and asked for a recommendation for what you are trying to do, one of the top recommendations would be the R7/HW30 (same gun). It is possible you have a lemon, but probably not. If you have access to a chronograph, velocity should be somewhere around 650 fps with an 8 grain pellet I believe. Someone else might be able to provide a better number for velocity. If you don't have a chrony, it should shoot through both sides of an ordinary tin can at 15 yards with round nose pellets.
Servicing airguns is pretty much a DIY thing, although sometimes there will be a local guy who will take it on. It isn't hard, but you do have to know what you are doing. Fortunately there are lots of videos on youtube, and forum guys willing to give free advice. If the gun does seem to be making reasonable power, and it probably is, you might be able to work some springer rated grease through the cocking slot and onto the spring and inner walls of the receiver until you can take it apart this winter for a proper servicing. But remember less is more! You only want a light coating of grease on the internals. Vortek and ARH sell lubricants. I will never put chamber oil in a gun again as it has caused me more harm than good.
The scope and mount recommended by Yo are top notch, and the scope is a great deal at $299. Just buy them, they will be used on whatever gun you end up using. I assume the gun has an aperture sight at the rear? With experience you can become proficient with iron sights, but a scope is always going to be an advantage, especially on game. The scope will also add some weight, which aids accuracy in a springer.
Pointed pellets have always been the least accurate for me. For shooting at any kind of distance I prefer the round nose field target style pellets, either JSB or H&N at around 8 grains for that power level. Although Yo keeps recommending the Premier HPs, so give them a try as well.
And lastly, springers may or may or may not respond well to standard bench rest techniques, usually not. Try one bag in front of the trigger guard, just in front of the balance point. At 10-15 yards groups should be 1/2"-3/4" to start, and can be much better than that with practice.