The answer I got was ...." I am stumped and didn't know that and would ask Engineering "
Next reply was...It appears that ONLY the round barreled .44 Carbines got the longer 17.5 barrel and the octagonal barreled .44 got the 16.5 barrel and
as to why he doesn't know! Maybe he might do some digging and find out the reason one day.
Anyway I did ask if I could send mine in for a octagonal 16.5 barrel swap and he replied that due to fixturing issues it couldn't be done in the plant.
But right after my first email about the issue I had another email from Henry that I had a free hat, coffee mug and key chain on it's way!
How many other firearm companies or any company can you talk directly with the head of the company and get immediate replies back!
So the real reason for this barrel oddity is still hidden in the depths of Engineering but I will sit back with my Henry hat on with nice Henry mug of coffee looking at my great pair of Henry Carbines and think was I the first one to notice the barrel length differences after 5 yrs. of production? Maybe!
