Need Help with Type 38 Head Spacing??

[1mark]

Took the Type 38 to the range. Using Hornady 140 gr 6.5. The primer is backing out. So I changed bolts and the same issue. I cannot locate any head space gauges for a Japanese 6.5.
Do I try and find another bolt or what??

http://www.fototime.com/inv/AE312819D6A17B7

[Parashooter]

Headspace with new or FL-sized cases in the Type 38 is controlled by the rim (it's what we call a "semi-rimmed" case), not the shoulder - and that control is somewhat marginal -



Since the backed-out primers indicate pressure too low to stretch the case walls and thus invite eventual separation, you really don't have anything to worry about with that particular batch of ammunition. Even with higher pressure that would re-seat the primer, the amount of headspace shown by the protrusion in your photos isn't enough to cause problems with good, new brass.

If you'd like to try an unconventional approach to eliminating the protrusion, apply a light film of lubricant to your cases before firing. With the right amount of good lube, your cases will slide back as pressure develops and re-seat the primers - without stretching the case walls. Although this will increase bolt thrust, a sound Arisaka action has more than enough reserve strength to handle it.

If you handload, partial or neck-only sizing can eliminate the cartridge end-play that is the root cause of the protrusion - by allowing the case shoulder to control end-play as with a rimless-bottleneck case.

[madsenshooter]

Yea, it would help if they'd make the semi-rim the proper thickness. I make my 6.5 Japanese from Krag or .303 brass, so that I have the right dimension. Lots of people get along shooting the undersized stuff, but I'll take all the material between me and the high pressure gases I can get. At least some of this newer brass is closer to the proper dimensions than the old Norma stuff.

[Sunray]

Clymer apparently makes 'em. Do not change bolts without headspace gauges. Bolts are not drop in parts.