You are on the right track, you test fire your pal's 82G and see how it does. It should shoot one ragged hole at 50 with ammo it likes. He paid around $425-600 for it, with included iron sights. A Weaver T-36 at 100 is an excellent practice unit for F-Class. I highly recommend sending the gun to Lapua, Mesa AZ. For $50 they test as many lots of ammo as they have, look for Center-X, Midas+ gets spendy. The only caveat to the Lapua test is you must purchase at least a case of your choice ammo. (5000) Also, you can purchase the ammo tested at Lapua thru "your dealer", like Clint Swigert of Precision Shooters, who will give some kind of discount. The 82G is economical enough to allow you to make the stock similar to your F-Class gun, cut away, add to, sounds like fun! BTW, I've got 4 Kimber 82G's, one 40X, 4 Anschutz, and a Pandaschutz, The kimbers hold their own!
willy