KIT: Parts I would assemble.
Example: I'm looking at the Lyman Great Plains rifle in either .54 or .50, but both have a 1:60 twist.
And I am preparred to spend bench time working up a load. "Shoot more . . . shoot more often"!
I know 300 yards is way out there with iron sights . . . just not sure what these types of rifles are capable of and would want to spend the money on one that can deliver ethical knockdown at distance.
I took my Antelope at 550 yards this year. I load my own and practice these shots though and am very confident in taking them.