I was loading some Sierra 168 gr. match kings for my .300 wsm. Having measured for a.o.l. a round should have been right at 3" exactly to have the bullet touching the lands, don't have the number in front of me. This , however, only seated the bullet into the case neck about a 16th of an inch. Seating the bullet deeper leaves to much jump before the bullet engages the lands. Is the only remedy for this to shoot longer bullets? And if I make them that long will they fit into the mag. The barrel is a Hart with a 1 in 10 twist. Can some one recomend a bullet and powder for good accuracy for punching paper.

A bullet does not have to touch the lands to be accurate. Try them seated deeper than 1/16". Shallow seating like that might work but the bullet may pull out of the case if you open the bolt on a loaded round. I have found that the runout gets better when they are seated a little deeper than that too.

As to bullets any of the Sierra line will be acccurate. You don't have to use MK's for paper.

Try 175 and/or 190gr SMK's. The Ogives up front are similar but of course the heavier they are the longer they are. Some rifles won't allow seating depths of more than 2.860 (some Remington conversions won't even allow that), you'll have to check your box to see if they fit and feed..........DJ

190gr Sierra MatchKing and Hodgdon H4831SC powder. Lapua brass and Federal 215 Large Magnum Rifle primers.