I've often wondered about the function of the rear stock cross-bolt (the one behind the magazine) on centerfire rifles--Sako and others. I had thought that the front cross-bolt (which is the only one on many centerfire rifles) was to somehow reinforce the recoil-lug area of the stock. However, after an examination of the inside of the stock on my new Sako 85 (pic below), both bolts seem to me to be far too thin and light to absorb much shock. So, what is their function? My guess is that it is to prevent the stock from bowing out around the magazine area upon recoil, since the broad heads of the bolts might keep the stock from swelling laterally. Is this it or am I missing something?