JeffinNZ
posted this
25 February 2008
Hi
My No1 MkIII is very fond of a 221gr bore riding bullet cast in clip on wheel weight with heat treated to 30BHN. I shoot it over 41gr of H4350 for just shy of 2000fps which basically duplicated the MkVI load.
The critical aspects of shooting the 'smelly' I have found are:
1) Heavy bullets with bore riding noses.
2) Correct sized bullets. My 221gr GC bullet .315-.316 out of the mould with the nose at .305. I size to .314 and seat in a neck expanded to .313 with the nose of the bullet just engaging.
3) I have my action bedded and barrel pressure pointed top and bottom from the barrel band forward. The barrel is locked tight between the woodwork. Knox form is floating.
4) Cases are neck sized only with a Lee collet die prior to expanding to .313 and cases are fire formed from new to headspace on the shoulder. Good case life ensues.
5) Necks are annealed every 5th firing to be sure of consistent neck tension.
Hope this helps.