[are there any special cleaning techniques I should know of relating to the BAR?]
Just like any other gas auto, don't let the gas ports in the narrel. or the gas piston, get lead fouled by shooting non-jacketed ammo - or you'll have a headache of a cleaning job to fix the resultant misfeeding.
And like the Remmy auto's, they're susceptible to all sorts of smaller woody "junk" getting in behind the closed bolt while hunting, and drifting down into the trigger group - which can be removed for a good clean/lube after removing the buttstock, if ever needs be.
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