Although I am not sure that it makes any difference in short range Benchrest, I don't believe that the reason for three lugs, on a target action has anything to do with reducing the degrees of bolt lift. I think it all goes back to some research that Creighton Audette did, using a two lug highpower match rifle, with heavily FL sized brass. I believe that it was a .308. The upshot of it was that when the extremes of case wall thickness (at the back of the case) were oriented in alignment with the lugs, there was less effect than if they were aligned at right angles to the lugs. This supported the idea that with rifles, and ammunition of that type, that the more evenly you could support divide support (lug contact with the reciever) around the case head, the less effect randomly oriented case wall eccentricity would have on overall accuracy. This is why some actions that were designed for prone type shooting have as many as four lugs. There is no issue with disturbing the rifle on the bags with higher bolt lift, and the nature of the ammunition favors that design approach. On the other hand With the typical brass quality and fit that is virtually universal in Benchrest PPCs, it has yet to be conclusively demonstrated that there is an measurable advantage in to be gained by using more than two lugs.