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Lacking a slug barrel, improved cylinder works best for slugs.
Can you shoot a standard slug threw a modified and or improved?
The only way to know is to experiment with as many different loads as you can find.
No however barreta 302 and 303 is the same gun browning built the b-80 under their patients and made a slug barrel that will match up to the b-80 for around $300 plus shipping
head
A rifled slug- yes.
Shooting rifled slugs is the ONLY way to shoot thru a smoothbore for deer. If you shoot sabot slugs thru a smoothbore, it will not spin and therefore not be accurate. For accuracy, the slug must spin out of the barrel. Either shoot a rifled slug thru a smooth barrel, or shoot a saboted slug thru a rifled barrel.
No.
yes
Any non rifled slug. However for best perfomance you want a "saboted" slug.
Yes, but from my experience not accurately.
No