Most barrels marked Twist are "Plain Twist", also called "English Twist" (even if made in Belgium) and "Skelp" (if made in England; and Greener called them "Wire Twist")...unless they are "Stub Twist"...which are different
It's sorta one of those 'I know what it is when I see it' deals
See
http://www.picturetrail.com/sfx/album/view/17227428
and
https://docs.google.com/Doc?id=dfg2hmx7_40dxk2scc7
and some of those "Twist" barrels could have been made by Parker
http://docs.google.com/Doc?id=dfg2hmx7_1742r4n6vcz
Just don't confuse them with "Faux Twist"..............Sorry
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