Not yet.

Back when I broke a lot of B-50 strings I was shooting the lightest, fastest arrows I could shoot out of my bow. Dan Quillian told me I was dry firing my bow with the light arrows which was causing the strings to break. Turns out he was right, bumped my arrows up 100 gr and never broke another string.

I shoot arrows in the 525-650gr weight range now and suspect this is why I never break FF strings. My strings are 12 strands of DF-97 with 4 strands of B-50 in the padded loops.

Any of you other guys who break strings shoot heavy arrows?