Hi James,,,
Welcome to GTA,, nice to have you with us. Congrats on the new Marauder,, I have one in .22 also and love it. I left mine at the factory 2500 psi settings and couldn't be happier. I have her sighted in with CPHP's and she shoots great groups. I'm patiently waiting for small game season to arrive here, which unfortunately doesn't open until November 1st.
Anyway, back to your question..................I would try Daves suggestion and try shooting without the baffles and shroud. As Dave said that should tell you if you're getting clipping in the baffle area. Before doing that though try shooting the pellets without using the clip. Shoot a group by loading them 1 at a time by hand. If the flyers disappear then it would probably mean the pellet skirt is getting deformed during the clip loading process,,,, which can happen with some pellets depending on their skirt thickness.
I have a question for you ... Have you lightened the trigger pull at all ???
Like I said, my rifle is still set up with all the factory settings,,,, with the exception of the trigger pull. I lightened it up 2 full turns and the difference was amazing. I didn't mess with any of the other "fine" adjustments on the trigger,,,, I just lightened it by 2 full turns. The reason I did that was because while my rifle was shooting very accurately I was finding I was getting some flyers that were driving me crazy. Lightening the trigger pull eliminated my flyers and helped me correct the problem.
I love my Marauder but I have to say that I personally have found it to be a bit "trigger sensitive". My trigger is now set to the perfect setting for me but even now if I don't concentrate and practice good trigger control I will wind up throwing a flyer. We all know the stories, which are of course true, about how installing one of Charlies GRT triggers in a GAMO rifle literally transforms the rifle and results in greatly improved accuracy,,,,,, Well,,,, same basic principle applies to all rifles, whether they be powder burners or air rifles. While we all know that there are a number of things that have an effect on accuracy I'm a firm believer that the major factor is trigger control. I have found this concept to be true for me when shooting any of my rifles and handguns, both powder burners and air powered.
Anyway, try adjusting the trigger to be a bit lighter and start shooting some groups. I'll betcha you'll see a marked improvement.
Well, I'll end here by saying once again..... Welcome to GTA :)
I'll be looking forward to your future posts.....
Jeff