So my Dad bought this 6.5×50 Japanese Arisaka 1927 type 38 rifle about a year before he passed , so it's been sitting about 5 yr and who knows how long before that .
I don't post often but I've been patching for several years with good success following the basics with my 50/50ish pistol alloy . I even killed a mule deer with a 200 gr PP in and 06' .
The Arisaka bore was a little dark and some scrubbing with brass brushes and a few passes with steel wool knocked most of the gravel out of the bore leaving a little bit of sticky not really drag or bind with a patched jag . Slugging showed me .258×.268 more or less but it would chamber a .278 as far out as .375 from the case mouth in formed 35 Rem . It's only about .280 in proper Norma brass but it touches the neck enough to scrub soot off .
Bare cast with a 270-140 FP NOE , 280473 and a .277-130 PC left an impressive even coat of gray haze with a couple of goobers . Accuracy ranged from palm sized with the NOE to 14" with the 280473 .
I proceeded with SOP and assorted bullets a 280473 sized down to .265 which wiped the grooves and the GC shank step . It shot about 4" with 9.9 Unique at 50 yd with the 280473 and just 46-48" with the Loverne 266473 both sized .265 .
Moving on , I expected very little with 160 gr start loads of H4831 at 35,35.5,& 36 gr . I was instead rewarded with about an 8" triangle at 35 gr and at 35.5 a roughly a 4×6 football shaped group . 36 gr delivered more or less point of hold for 2 shots about 3" and 3 off in parts unknown . I did get some confetti a bit of land marked and what was a still folded base . Mostly just poof dust .
With that known , I dry wrap , folded tails , from some old school calculator tape . The goal was to clean up the bore not shoot groups but if you're doing it you may as well do it right . I should add that the trigger is 2 stage of about 3.5# of take up , 7# to break , and the sights leave a little something to be desired . But I feel like my hold is good and follow through isn't horrible . The last part is that this is Metford rifled so I doesn't have a hard edge to cut patches in fact I can see where if the patch doesn't spin or parachute off and stays intact it could ride along quite a ways .
I'll try to get some pictures of the bore as is with a picture of what I started with .
Any experience with Metford rifling or other no hard edge polygonal rifling ?
Am I headed the right way when I go to green bar paper ?
Should I write a whole process of getting there like it's new ground ?