Riser Breaks...

[Shredd]

If I want purdy I'm putting my tools aside and buying a Blacktail...   

[kennym]

I'd have to use my other tools a while to get one o those!! 

[Shredd]

  True, true...    

[Flem]

The one on the right, the brown wood broke at some transverse grain, wood failure. The one on the left failed because the portion that needed to connect the limb pads, was not continuous. Design failure.
Unless of course they used crappy glue, or made some construction error, or........
Considering we know squat about these risers, its all speculation.

[Arlo]

Both broke on a glue line, after the break starts, it can do some strange stuff. 

I think that's a good possibility that it was phenolic or glass accent line. That and a bad placement where the accent line comes through the throat.

Footing and accent lines need to either run full length of the riser, or be capped with an overlay or the limb pad cap to keep it from separating. You need to always cap end grain. That's the weakest spot.

Poor design IMO     

Arlo