how you can tell if its in semi and not ramping is when you pull the trigger and if you listen closely you can hear a little ting sound almost and if you walk it and it tings faster then your fingers or going its ramping

or #2
you just watch the led when your walking the trigger and if its in non vision mode it will blink for every time the gun would normally shoot and if it blinks faster then your trigg walking then its on ramp not semi

and #3
when you dry fire it you can usually tell the difference