A couple of thoughts...
Got that rear bag yet? No, get it ordered, it'll make a world of difference.
Experiment with your body position.
- You want to find something that is relaxed, specifically you do not want to have tension in your body.
- A key part of it will be finding your eye/head position. You want your eye looking straight down the scope tube. Since you have the adjustable cheek piece on that stock, use it. You want to find a repeatable "feel" on your face. A lot of people rest their cheek bone on the cheek rest for their feel point.
- Preload the bipod, if you're not sure what I mean, Google it, lots of better explanations than I'm going to articulate here
- No tension points in touching the rifle. Don't push or pull the rifle. When you have a rear bag you want it loose enough you can squeeze it to make slight adjustments in POA.
- The RAW's have EXCELLENT triggers, take advantage of them! Slowing move through the first stage, hit the second and follow through. Straight back, hold it till you see your pellet hit the target.
- Build a relaxed, meditative routine to taking a shot. Slow deep breaths, seriously breathing will help more than you can imagine! Do it the same way every shot. Chase stray thoughts out of your mind. Its normal for your mind to wonder, just come back to what you're doing and keep going.
My breathing technique before I start a session... (10) deep breaths. In slowly counting 1 to 10, out slowly counting 1 to 10, (1) breath done. Repeat tens times.
My routine... look through the scope, I have a touch spot on my face on the stock to insure center line. Adjust my rest to something close to my POA, come off the rifle, pull my bolt back, pick up a pellet and feed it, close my blot, 3 fingers on the grip, thumb straight up behind the grip, head down hit the touch point, trigger finger along the stock, look at the target, make fine adjustment to the rest, finger in the guard, slow deep breath, relax, finger on the trigger, exhale slowly while moving through the first stage of the trigger, move through the trigger till it stops on the natural break between exhaling and inhaling. Slowly inhale, spot the shot, make mental note of any difference from POA and POI. Repeat for the next shot.
There is the idea of "free recoil" in bench rest shooting, again Google for best explanations.
Are you using the same pellets Marksman was using with it?
Make sure you are staying on the regulator! I'm not sure with a 25cal how many shots you should expect, but sort out your pellets before you start shooting in groups of whatever number that is. Take a test shot or two after a refill. IME my BM500x doesn't change POI on the first shots after a refill, but some have reported they see one.