Seriously... a gun bag. Buy one - they're only $26 (I bought mine for $80... damn! ... Anyway...) put a broom handle in it to stop it flopping around, throw it over your shoulder and ride.
I had to bring a rifle into town this morning for a wee fix up and the cars were parting like I had Moses himself waving his magic wand. Bloody awesome!
Funny what it says about bikes not being seen too... people will see you if you're a threat...
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