I've been playing around with a sporterized type 38 Arisaka that still has the original 6.5 military barrel. But, had been rechambered to 257 Roberts a long time ago....so the cartridge for it is a 6.5x57, aka 6.5x257R.
When I first began reloading for the rifle, groups at 100 yards were pretty bad....4" or more. Tried various powders, experimented with different bullets and etc. Got 100 yd groups down to maybe 2".
This week, tried some reduced loads with IMR SR4759 with 85 gr, 120gr and 140gr bullets. Was only 75 yds, but Egads, the 85 gr bullets were less than a 1" group...3 clover leafed, one bullet hit about 5/8"" outside them. The 120 gr bullets were about the same...3 cloverleafed, 4th ruined the group. The 140gr didn't clover leaf, but produced less than a 1 1/2" group. Returned the nexst day with more SR4759 loads. Seems rifle likes 120gr or less bullets with the SR4759.