Break In -

( Presuming we don't mean custom built extra tight target 1911 or such ) , most current era firearms intended for potential Duty Use require little to no break in of the Firearm itself . ( Of course , strip down , clean, and suitably lubricate before using .) If something is initially defective , it will *usually* show up imeadately .
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However , I personally err on the side of caution as to compatibility of particular Ammunition in particular guns .