Thanks, I had a pile of liners, after I installed the liner I noticed an old instruction sheet from Chambers in the bottom of my parts box, 82 degrees is what they recommend.
I bought a Track Issac Hanes kit a while back that someone put up for sale on a free archery classified. Inside was every drill bit, tap and countersink for completing the rifle. I tried the 82 degree they supplied with the kit, it didn't like cutting a Green Mountain barrel at all, pretty cheap.