it could also mean the barrel twist rate. but, generally means its a heavier, bull barrel
I have been a silent witness
to all of America's finest hours.
But my finest hour comes
when I am torn into strips and used as bandages
for my wounded comrades on the battlefield,
When I fly at half-mast to honor my soldiers,
Or when I lie in the trembling arms
of a grieving mother
at the graveside of her fallen son.