i am begining to shoot long range with my 7 mag. i thought i would try the 168gr sierra matchkings. would r22, h1000, and h4831 be good powders to try? any other recommendations? thanks for all your help.
Looks like you are on the right track. My favorite is R22. Probably the most recognized powder for the 7mm is H4831. SMK's generally offer the best combination of price, BC, and accuracy, but check out Northwest Custom Projectile www.customprojectile.com They make a 162gr. hunting bullet which you would be able to shoot faster and it has a BC of .559 vs. .49 of the sierra. (Tell him Kevin sent ya).
Try 150 Nosler Ballistic Tips and 67.5 grains IMR 7828. This is a Ken Waters pet load combination and has worked very well in my fussy Sendaro in 7 Rem Mag. This is near max in my short bthroated rifle so you may want to start at 65 and work up.