The "through chuck"idea is what I meant by spindle boreApprox1 3/8 in allows a 5-c collet setup,which is a very useful thing.
A taper attachment is handy
A South Bend such as this one,if the link works,is a pretty good gunsmith lathe
http://www.ebay.com/itm/HEAVY-10-SOU...item4ac1e528c3
I ran one of these for years,stout,precise,rigid,excellent for threading,one of the finest small lathes ever!But maybe more than a hobby gunsmith needs.
http://www.ebay.com/itm/MONARCH-10EE...item2ec71abd51
In between,this Harrison is a good machine
http://www.ebay.com/itm/13-19-x-25-H...item4abf6e25b9