>>64362711
I unfortunately don't have any unfired .410 to check. Looks like rounds should easily load if dropped straight on the mag follower they threw on top of the wood block in the magwell. Seems they beveled the lower edge of the barrel. With a nice round edged 410 cartridge I don't think you'd have issues. Probably varies gun to gun. Still available last I checked @ centerfire but needs to be bored to accept .410 shotshells unless you want to fireform .303s to IM .410 and load those shells like you would a .410. Just copying from an old reply of mine:
https://centerfiresystems.com/ishapore-no-1-mk-iii-shotgun-model-410-musket-surplus-incomplete-c-r-eligible/
But note that these do NOT come with a bolt! Barrels are a whopping $40 lol.