Range balls causing crack?

[WUTiger]

Any chance you were banging away on battered mats over a concrete base?

If you cracked both the 5i heads at the same driving range, you might consider the condition of the mats. (From November to mid-March, our course range makes us hit off the mats unless you're teeing up a driver.)

Maybe 10 years ago, I saw a driver with the face caved in by a high-speed swinger. Compared to drivers, however, irons have a much denser head.

(I cracked a driver head back in the 1970s, but it was a wooden Wilson Staff.) 

[Hacker James]

I can see where the cup faced drivers might be susceptical to being damaged, but not irons. I would side with @WUTiger in regards to possibly the hitting surface being the culprit. For decades people have been hitting range balls with persimmon with no undue ill effects, but I suppose we could consider that the covers were not as hard back then and thus a little pliable. In any event, if it were me, I would exercise on the side of caution.

or......start going to higher class driving ranges that use better balls. (yah, I know,not necessarily feasible).