Depends on age of the barrel, forcing cone type and the shot used.
a new Remington 870 will not scratch.
an old Winchester m12 will scratch when using steel. lead is good for old barrels, steel wrecks them.
Focus on the target, ignore the barrels.
One or two, depending on how many barrels the shotgun has.
AFAIK, no.
both barrels are not choked
Store brand shotgun with two barrels, side by side.
shotgun is the answer shotgun is the answer
Try e-gunparts.com
One can practice shotgun shooting in more than one place. If you have enough land you can practice there. You can also go to a shooting range and try there.
That would depend on the make and model of the shotgun in question,and the length of the barrel/barrels that came with the shotgun.
No
atchison automatic
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