S spikeyken Member Joined Apr 21, 2007 Messages 7 Reaction score 0 Apr 21, 2007 #1 Hi all, Does anyone know the inside diameter of a H180W fuel grain please? Thanks, Ken
Chicagonative17 Well-Known Member Joined Jan 31, 2009 Messages 1,590 Reaction score 0 Apr 21, 2007 #2 Why?
outasight13 Well-Known Member Joined Jan 20, 2009 Messages 1,043 Reaction score 0 Apr 21, 2007 #3 A tiny bit more than 1/4".