Arisaka Type 38 long rifle and bulged 6.5x50 cases
I have an open question about my Arisaka Type 38 rifle.
I picked it up in a big rifle trade I did a couple of years ago and other than having a slightly defaced mum, it is in really very good shape. The bore is nice, there is a nice crown and it is acurate and has a pleasant recoil.
My problem is the bulged cases. I have fired Hornady 6.5x50 in this rifle and I get bulged and somewhat asymmetrically deformed cases at the base. They are deformed to the point that I wouldn't want to reload them. Considering how expensive Japanese 6.5 brass is, it would be nice to reload them to make shooting the Arisaka a bit more economical, but I don't dare reload these. The primers are not bulging out and none of them are pierced and I have never had a case head failure, ruptured case or a failure to extract, but the brass is bulged at the base.
I understand that the headspace is likely to be rather 'generous' more probably due to the way it was manufactured (being a combat rifle designed to function in the tropics when it was dirty, and generally speaking military specs are a lot more generous than SAMMI) rather than throat erosion, although that could very well be a factor.
Has anyone here ever removed the barrel and turned it down a bit at the shank where it meets the receiver and then shaved off some threads and then re-bored the throat to specs? Arisaka is supposed to have the strongest action of all the bolt action rifles of that era, and the 6.5 caliber round pressures probably give some room for working with it.
I'd like to shoot it more because it's a fun rifle, but the ammo is a bit pricey and if I can't reload the brass a couple of times, what is the point or reloading?
If anyone thinks I'm nuts for considering this on a Milsurp rifle or if this has beaten to death on another thread, then I apologize in advance, .......... I'm new here.
04-02-2011 03:00 PM
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Headspace is likely OK. Just neck size, it'll be fine! They all do it.(bulge at the base in 6,5x50, that is.) Norma, Hornady, whatever. Maybe the AMMO is wrong?
BTW, A couple of years ago, as a test, I shortened and fired .303 British brass in a 7.62x54r rifle- and then did it again with the same brass! 30-30 DID rupture- but that's a HUGE mismatch!
Will link to that thread when I find it.
---------- Post added at 02:58 PM ---------- Previous post was at 02:49 PM ----------
The old experiment- which was performed after much rancorous debate, which you may or may not want to see- there's some good stuff in it, but plenty of fur flying as well. Different thread, fortunately!
Click on link below:
Oversized Chamber Experiment
---------- Post added at 03:06 PM ---------- Previous post was at 02:58 PM ----------
See also this thread:
Why there aren't Japanese rifles among "favorite WWII rifles"?
Posts #34 through #37
Really Senior Member
I have both Type 38 and Type I rifles in this caliber. The chambers in all 4 are much larger than the brass. There is nothing wrong with the ammo or the rifles there is just a lot of clearance designed in. You can make better fitting brass out of .303 if you are willing to do that much work. You can also swage down .308 size cases if you have a big press.
If you wish to do so you can partially full length size the cases just enough to get the bulges out without any worries. A while back I performed one of those wonder what will happen type of experiments with a T38 just to see how many times a single case could be loaded before it had head seperation. I took a Norma factory load and proceeded to load and fire( FL sized each time) and the neck split on the 12th shot. Next one I annealed the neck after the 10th shot and got 14 more loading out of it until the neck came completely off on shot #24. No head seperation. One day I'm gonna do the same thing with a PRVI case.
Last edited by vintage hunter; 04-04-2011 at 10:37 PM.
You can reload with no fear of head seperation if you will watch for a white line just above the web. When you see the thin white line, most likely the head will seperate on the next shot. But even if it does its not big deal, you are in no danger of getting hurt. To get the seperated case out of the chamber insert a cleaning rod down the bore, attach a 45 cal cleaning brush on the rod, pull it back into the chamber and then bump the rod and the case will come out. Unscrew the brush from the rod, pull the rod out and you are back to normal. As to the bulge, thats normal. You could wrap on round of 1/4" masking tape around the base of the cartridge and that would center the case and the bulge would be spread all around and not look as bad. If you will back off your full length die and not size the whole case your cases will last longer and fit the chamber.
Someone m entioned taking the barrel out and setting it back a thread. A friend came by couple of months ago with a beautiful sporterized T38 that the bolt would not close on a cartridge. It appeared that someone had set the barrel back and did not have a chamber reamer to deepen the chamber. I used a 6.5x50 finishing reamer and got the bolt to close and correct headspace. Sometimes when you do this you also have to remove metal in the mouth of the chamber or the bolt will hit and keep it from closing. Some years ago I made and sold a bunch of dies to resize the base of 308 win brass so it could be resized in the Japanese die. It corrected the chamber bulge. Since Hornady and others sell brass and loaded cartridges there has not been the demand. Unless the primer blows out when your fire the rifle, don't worry about the bulge.
6.5 x 50 buldged cases
The 6.5 Japanese cartridge is a semi rimmed case. Semi rimmed cases headspace on the rim not the shoulder. The rim dimension (thickness) should be .060. the case should be 6.5 x 51 rs not 6.5 x 50 and ocl should be 2.008 inches. The Hornady cases I believe are made by prvi Partizan and should work correctly. I have able to fire them without buldging. Norma has changed their case dimensions to provide a .059 - .060 rim thickness and these newer cases should work fine as well.
Thank You to kamzac For This Useful Post:
I've a bunch of old 6.5 Japanese milsurp ammo in boxes and on chargers/clips. Having done some cursory measurements around the base area (not a detailed study!), I believe ireload2 is correct- the ammo is just smallish as regards the chambers.
BTW, a quick check notes that Cartridges of the World and Sierra both list the 6.5 Japanese as 6,5x50. From where they got the terminology, I've no idea.
mine shoots the same cases bulge slightly however no one wants a case failure first do run empties thru full length sizer leave the lower third alone sier weakens brass when moved a lot . it was made to take about anything . the bolt of the rifle has a failsafe built in the big old nob safety also ws purposely shaped to redirect gasses from a ruptured case . buy a nice pair of safety glasses to use and enjoy.