Bob - No, ruger didn't reccommend it. But after hearing of others splitting problems w/ the wood stocks, I decided to be proactive and add it before I ever shot it. Same w/ the 1" decelerator. I don't know about what it does to the warranty, actually never thought about it till you said something! A friend of mine w/ a milling machine bored the stock for me. My rifle came w/ medium height rings, and I wanted lows, so when I called ruger CS about exchanging, I asked if I could purchase a factory crossbolt, so it would match the other. The lady who helped me said no problem, she'd just include it w/ the ring she was sending, no charge..........
