If you're going to do serious reloading, you need a cartridge overall length gague..It's important to know where your bullet is in it's relationship to the lands..otherwise follow the manual COL as it is listed for that particular bullet..Stoney Point(I think Hornaday sells it now) is what you want..You have to practice with it a little to develop your technique with it..taking several measurements until you get the feel of it..I think it is a very good tool and easy to use..it is a "must have" tool for accurate reloading IMO..I would start at about .025 off the lands and work in with .005 increments..for hunting ammo I'm usually no closer than .010 off..remember, If you are very close, or IN the lands with a hot load, you may have very high pressure!..I knew a guy who blew the bolt right out of the gun doing that!..you might find that your magazine box will limit your OAL, or your magazine will hold the length but you can't chamber it..so..read a lot, and take careful measurements..reloading is all about measurements, and seating depth can make a big difference in the accuracy department..
art
