Any tips on sighting in a Center Point scope?

I have a Crosman Nitro Venom with a Center Point scope. I have a pellet trap about 15 yards away, and I CANNOT get a small group. A few shots will be near the bullseye, some are low, some are high. I'm also using a gun rest to keep it steady.

Does anyone have ANY tips for getting an accurate, small group?
 
well there's a few things

​clean the barrel and then shoot t relead the barrel see if your groups tighten
try other pellets
​chronograph string t make sure you getting a consistent fps
​ive heard/seen that some times ther breach where you seat the pellet the oring need shimmed of replaced causing a seal issue wich can cause fps issues now if there shooting just high and low and not pulling to the right or left I can see that being your problem
 
A safe place to start is with Crosman domed pellets. High probability that gun will work best with them, at least a domed pellet. As mentioned above, many springers are sensitive to how you hold them. That is why I switched to PCP, because I could not consistently hold my Nitro Trail in hunting situations. Be patient. If you have made large adjustments to your scope, you might be past the turret spring limit and need to recenter the reticle.
 
In addition to the ideas mentioned above, you should check to see that your stock screws are tight, there are two near the barrel pivot(one on either side) and the larger of the two trigger guard screws. Don't overdo it, just snug is good. If they come loose a lot you might want to put some blue loctite on them. Don't hold the gun tight to your shoulder like a firearm, use just enough pressure on your shoulder to keep the butt stable and hold the forearm lightly at the balance point in front of the trigger and try to be as consistent as possible with your hold. That series of guns have awful triggers, you can get aftermarket ones from AOA. 
Good luck and keep us posted,
John
 
I just checked and they are nice and snug. I understand the artillery hold, I just have a hard time doing it because half of my fingers were amputated so I can barely reach the trigger. My dad agreed on the horrible trigger and put a different one on that he said was made by Charlie Da Tuna.

Because of my hand condidtion, I feel like without a rest, I have a hard time following through with my shot. I got a headshot and a ring neck yesterday and I was aiming at the heart.

Would you recommend sighting it in without a rest?
 
Don't know how old the rifle is, but try this-with the barrel closed and locked up, see if there's any side to side play between the barrel and compression tube. If the barrel seems floppy it's possible the plastic pivot bolt washers are worn. I think that series of rifles all use plastic washers on either side of the breech, kinda bums me out because the one I got for a neighbor had a good barrel and shot pretty well-for a while! I replaced the washers with brass ones and it helped but didn't restore the accuracy as much as I'd hoped.
John
 
That series of rifles uses a sleeve between the breech block and the barrel pivot bolt. This allows the possibility/probability that there will be play or wobble movement of the barrel when closed. Here's the address of the parts diagram(don't have the know how to get you an image).
https://support.crosman.com/hc/en-us/articles/203361814-CVW8M22NP-Owner-s-Manual-EVP-2011-Current-
click and download the parts diagram
If you study the parts diagram you will see a sleeve that goes into the breech block. To answer your question-It MIGHT be fixable (with a ton of skilled work), Guess it wouldn't hurt to see if Crosman would send a new barrel, but I'd advise you to try again with a different rifle. As far as I'm aware, pretty much all the Crosman/Benjamin break barrel rifles use this pivot sleeve and the plastic breech washers. My limited experience with these rifles has not been positive though there are many here who seem to have had good luck with their guns. I would strongly recommend you to look for a used or refurb RWS34 (Airgun Depot has refurbs from time to time) or a Ruger airhawk or Blackhawk which are clones(copies) of the RWS 34. If you can stretch the budget to $300, the best deal going is AOAs HW95. 
Good luck,
John