one of the first purchases after getting a marker should always be a chrono. You cannot safely play a game unless you know exactly how fast the paintball is moving. We cannot tell you much without you telling us your paint's speed but I might suggest that perhaps your APEX is doing the intended job but you need to raise your muzzle more. Chrono your marker to about 280 fps and try it again. Do what you did last time and see if it's stillacting up. If yes, raise your muzzle about 5 inches and see if the paint starts to climb higher. If that's the case, your APEX is working but you need to aim higher for it to do the proper job.

If not, there could be some broken paint stuck in your breech-to-muzzle area, that's causing an issue for you.

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