All non-sniper rifles are required to be 400 and under, while sniper rifles are allowed to be at 450 and below. They do have a make-shift tech shop. You might be able to get them to lower your FPS via a lighter spring for your AEG with a service fee. I wouldn't bet on them doing it for you for free, due to liability issues that may occur when opening your gearbox.
You will have to adjust your own velocity. Sometimes they will do it for you for safety reasons.
I'm not sure because I'm very new to this
I'm not sure. I've only been there once
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