I started to shoot a Hill style longbow recently.  I am getting very decent accuracy using a 68 inch longbow.  I draw 30 inches.  Why am I catching the corner of my chest on my bow arm side?  Any ideas?

It sounds like you're either going to have to go to a more open or a more closed alignment.  With a more open alignment, your chest should be back away from the string.  With a more closed alignment, the string might have clearance to the side of your chest.  Either Darrel Quidort or Denny Sturgis (I forget who) demonstrated this pretty well on MBB III.  It's easier to see than to describe.

I shot a 68" Hill with a 30" draw also.  When I caught the corner of my chest, it meant my left arm was locked and not in line with my shoulder.  I shortened my draw length to 28 1/2".  I got more consistant and arrows are easier to tune.  Bill

Bow is canted too much.  Straighten it up.

Well, it seems Bill Skinner was right.  I was overdrawing the arrow to about 31 inches.  I am only 5'7" with a 6'3" wingspan and have to draw around 29 to 30 inches to get good alignment.  Sometimes I over draw when I emphasize my back pull.

Three Arrows, I had that problem when I went back to the longbow after shooting a compound for several years. I thought I needed to draw it to 30" like my compound, and when I relaxed to a proper (for me) 28" draw, the problem was solved.

try a shorter draw length. lean forward at the waist and get a good cant

Why would you have a longer draw with a compound than with a recurve or longbow?

I too was hitting my chest on the bow arm side (shooting longbow, three fingers under).  By not locking my bow arm, i.e., making certain that the arm was bent, the problem was eliminated.  My tendency with a push pull draw was to lock the bow arm as something to draw against.  Doing so put the bow arm out of alignment and caused edge of the chest interference.

I agree with the cant of the bow. I kept hitting my under arm and short sleeve and could not figure out why. I opened my stance closed my stance and nothing worked, then while bareshaft tunning my arrows I held my bow straight up and down and it went away then I just didnt cant my bow as much and wala it's gone..
Terry