Another tip with public transport is to think twice about your choice of bags.
A gun bag is designed well for the purpose, but looks like a gun bag
Consider other options, eg a sports bag or hold-all rather than a dedicated gun bag, or alternatively an outer bag - I have a snowboard bag that I used to use with gun bags inside it, that was more for the convenience of storing and carrying two or three gun bags at once from the back of the car onto the site but it also anonymises the contents
(It would have been useful on the day that my car was parked on one side of motorway services and we had traveled on as a group getting dropped off on the other side. My team mate passenger was not so good at luggage and had also bought another gun with no bag or case - We had to make multiple trips due to the amount of gear, wrapped his in dirty playing clothes, met coach loads of pedestrians on the bridge in the opposite direction and as I had parked in a distant quiet part of the car park the motorway police had decided to meet up for their coffee and donuts next to my car - a big anonymous bag with lots of spare space would have been useful
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Regarding spare clothes consider them for multiple purposes:
You can avoid looking like a gun nut on public transport
A clean set of clothes feels so good after a days play
Depending on venue, weather and your style of play - if you have extra carrying capacity some spare playing clothes can let you be dry, clean and comfortable especially if the site breaks for lunch - it’s then that you cool down and feel grotty after crawling through mud earlier on. Fresh playing clothes reinvigorates you