I have built most of my parts guns on Remington 700 series actions because they have generally been less expensive to buy and there were far more after-market part options easily available. When I started building parts guns in the mid-1980s, there were lots of Remington 700 and 722 donors that could be bought for around $150, but not nearly so many Ruger 77s in the same price range.

The only Rugers that I've put together were in the RSI configuration, because I like mannlicher stocked rifles and 77 RSI stocks are the easiest mannlicher style stocks to find via the internet.

JEff