increasing the amps will increase penetration and is usually done with wire feed speed or stick out
Of course it dose. If your using a mig process constant wire feed if you increase your stick out your amps will drop and so will your level of penetration. Vica verca if you decrease it. The arc length will stay the same with mig because it's a semi auto process unlike tig and mma.Care to explain how stick-out affects the current?
Weld a 100mm run with a 10mm stick out then do the same with a 40mm stick out.
Are you telling me the depth of penetration will be the same if you keep all other conditions the same.