just started loading for the 7 mag bought some 168smk's these bullets appear to be very long and when seated the base appears to be below the shoulder of the case will this cause any problems or does this happen on certian bullets.

It's common, and causes no problems if it does not compress your powder charge excessively (to the point that the bullet or case is deformed). But try seating out as far as your magazine will allow, so long as the bullet does not engage the lands.

Seating a bit deep is fine with copper jacketed bullets, but cast bullets can't be seated with protrusion.