ISO: Italian bread keeps spliting apart where score is when in oven...help?

Hello!

I keep trying to make some Italian bread but always have the same problem...the bread, where scored, keeps expanding/ripping too far when in oven.

My bread seems fine except for this 'problem'. The only change I make from the original recipe is to combine all the dough, the recipe calls for 3 loaves from the dough, to make one loaf. The reason I combine all the dough to make one bread is this: The original recipe calls for 3, 7seven ounce loaves from the recipe, and I find that that doing this makes for too small a bread...so I make one large bread with all the dough.

Now, could my problem come from my combining all the dough together and not making the dough long enough? So that when in oven it burst open at the score and leaves rip marks along score line.

THX