How to tune a Bobcat MK2 .25 cal?

In reality, while there are probably a few things that can be done, a new Bobcat should need no tuning. The FX guns that I've had out of the box shoot lights out and will stack pellets and need no tuning. Are you having any accuracy issues specifically that can be addressed or are you just asking about tuning in general?

Trying to put the finger on the exact problem is like trying to get your hair cut on the telephone but here are some thoughts. 
1. Did it start spreading after you added the LDC? Might try seeing what it does with it off. Could be clipping. Look for lead particles. 
2. Have you put it thru the chrony? Make sure you are getting consistency there. 
3. Does this gun have a power wheel? Make sure it is set properly & not a little off. 
4. I don't use cleaning pellets cause I want to actually see what might be in my barrel. If it shows lead particles that would indicate clipping. 
5. Use a light and carefully inspect inside the LDC and in the barrel too if you can. 
6. If it continues I would describe the problem in detail and call AOA. I believe the gun will still be under warranty, if so, AOA will send you a shipping label. They will fix it. If not under warranty, I would still send to AOA cause they will fix it. 
Hope it's just something minor cause this very aggravating. Good luck!
chuck

Added: Make sure the scope is tight. Almost didn't add this because it's rarely the case. 

Haha Longbrownbox, got a good laugh at the "haircut over the phone" comment. I agree though, difficult to diagnosis over the forum. AOA will get it set up in no time at all.

Vudo: the things recommended too you are very good troubleshooting. I want to add another thought. I shoot a Bobcat mkl and my POI at 50 yards would be .3-.4" then after 3 shots 1" off POI and all 3 shots hit within .3"-.4" again. My scope internals failed . Changed my scope out and all is well again. Your gun is very capable of 50-70 ,yard shots consistently.

Those groups look pretty good if it's been shot in windy conditions. Check your trigger pull. If you are pulling your trigger a bit fast, your groups can move to the left or right. Try shooting by following through with your trigger and slowly squeezing it, your groups should improve. 

Groups dont look bad, I would say you might be canting the rifle which is easy to do with the bullpups. I don't care for how the shroud is on the bobcats, try removing the end cap and shooting without it. More of a free floating barrel. You can also play around with velocity to see if the barrel might like a little more speed. Do you purposely have the poi and your poa off for your groups?. I find all the st fx barrels I have are very pellet fussy, some claim theirs are not but having had 6 different fx st guns they all were for me. I have done various things to FX guns to help accuracy, have modified magazines, opened holes in stripper, opened bore in endcaps, opened holes in FX baffles, adjusted shrouds on bobcats. I have had st barrels that would put 5 pellets into 3/8 at 50 using jsb 18 then shoot some h&n pellets and literally only one pellet even hit the 8" square piece of paper.

On your target you say target.....but group is to the left. POA POINT OF AIM..... some people set scope to group off of where they aim to keep a good aiming point. The easiest is to turn in the hammer spring tension screw to raise the velocity. Turn it a little at a time and check velocity and shoot some groups.

The screw can back out during use if it doesn't have some thread lock on it. Also check your barrel screws to make sure they are tight. Is it regulated? 

Vudo, I see you have been given more great information for troubleshooting that POI (point of impact) change. Let us know how you come out. Try not to get frustrated you will get it figured out with some time.

Vu, more FPS doesn't mean more accuracy. I don't remember what grain pellet you are using. The JSB .25 gr pellet will shoot about 100 FPS faster than the JSB .34 gr pellet. I stick with JSB pellets but I would try a different weight. My FX 500 loves the .25 gr but my regulated FX 500 likes the .34 better. Both are .25 cal.
we all seem to want more FPS but be very careful if you adjust it. A small adjustment can make a big change good or bad. 

vudon, sorry must not gotten your email. Email me: [email protected]

to properly trouble shoot your BC;

1. Shroud removed --- just barrel and check for proper mounting---> take 5 six shot groups from 200 to 175b if regulated if not find the flattest string and take group accuracy @50y

speed setting with above testing;

current speed to around 20fps increments till max speed is reach,if possible around 925fps (most ST barrel like this speed and some don't like it slow)

2. Install a barrel that I know is accurate and take shot string with the same setting as above

if accuracy are similar with no issue then shroud reinstalled with end cap and take group accuracy as noted above and compare groups, install NC LDC and take group accuracy as noted above, look at all the groups and compare--most like you can pinpoint issue area.

your current groups are pretty decent -- there are so many variations to have that groups and many more to get it tighter.

notic your power wheel on #2, it should be set to the largest TP hole, with a smaller TP aperture accuracy always open up. 

yes the power wheel has 3 different size TP hole