Most of the local Regina WestJet staff are use to Airsoft guns from all my years of travelling, and have become well versed in what they are. Security on another hand changes so often that they continuously have new staff.
In my 8 years of travelling with them in my locked suitcases I always just filled out the declaration form at the counter, which when you read it has a section for paintball/co2 guns on it. Considering over those 8 years, I did an average of about 120 flights a year, and only once had a RCMP visit in Vancouver due to a panic'd xray tech there, I'd say its perfectly safe to fly with them if done correctly. That time in Vancouver, I got to watch the 2 RCMP officers search my luggage and then play with my guns on camera for about 25mins, even posturing and posing with my M500 shotty. The westjet agent who was sitting with me laughed her ass off at them and said well I'm pretty sure at this point were okay to let you back on the plane.
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