When I started cleaning my Ruger M77 Mark II in 257 Roberts today I made a mistake and patched a 30 caliber cleaning rod. The rod easily startes in the chamber and fits loose until it hits a spot about 12 inches down the barrel, it stops like it encounters a stuck bullet!

I measured the rod at .249". Out of curiosity I tried putting the rod in from the muzzle, no way.

The rifle has actualy been shooting some decent groups but with at least one crazy bad flyer out of every five shots.