I've had a few early war Arisaka's in 7.7. Various barrel lengths etc. I've shot them all and they all shot well with open sights.

Someone was getting rid of a "Last Ditch". I figured what the heck. I could use a spare bolt, etc. I've had it for years actually and finally decided to try shooting it. I checked the head space and action feed prior to taking it out but I "DID NOT" slug the bore. I just "eye balled it" like an idiot.... It looked good.

Turned out I couldn't hit the side of a Mack truck with it. I was amazed. Some of the rounds even tumbled.

So, finally to my question. When I got home I slugged the bore. What I found was astonishing to me. The bore mic'd at .304, .308, .311, .317, .319..... depending upon what side of the bullet you were measuring. So I slugged it again and found the same results. The slug actually has rifling on it. Well, some of it does.

I've never even heard of a out of round bore before. I've seen plenty of shot out bores but out of round?

Question to the Arisaka collectors. Have you ever seen this before? I'm not sure how "late War" this gun is but it's a short rifle, 3 nails in the butt stock, late serial number.

Murph

Just when you think you've heard and seen it all. Never say never with milsurps.

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Release the Kraken

The best I can say for mine is the bullet goes more or less in the direction you pointed it

I think I'd hang that one on a wall.

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No baby we aint

I have a very nice last ditch bayonet. Very crude compared to normal jap bayonets.

I’ve had a number of Last Ditch rifles, but never thought to slug the bores. The ones I shot were all Type 38’s, 44’s, or early to mid war 99’s.

I guess if you want a accurate shooter you should probably stay clear of the late war Or “Last Ditch” rifles. The U.S. was bombing Japan at will during that time so the quality of the Machine work was obviously impacted greatly. The various arsenals were often a primary target.

I’ve watched a few videos from Japanese WWII rifle collectors claiming the late war guns are still OK and even claiming the Japanese were actually only streamlining the manufacture.

This one sure isn’t! In my opinion it’s original work. Looking down the bore you can clearly see rifling all the way. So it was poorly manufactured like this. I think it’s obvious that the shop conditions were in a desperate state.

I was thinking about changing the barrel since I have a couple early war barrels but I kinda like the history here. I’m thinking I should leave it alone.

Murph

Come in for the big win…M1 Garand…just kidding brother, thanks for posting.

Even the late war 99s had chrome bores for the most part. But I think some of the very true last ditch models did not. Is the bore chromed? Maybe the bore never got completely finished on your rifle.

No chrome lining. I’m looking up the markings now. I’ll post what I find. I took a really good look at the machine work and it’s sloppy. The exterior of the barrel is uneven with clear mill marks. Zero effort to complete the surface finishing. It was hastily done.
I also looked very closely for any dings, dents, bulges, anything that I might not be seeing through my shop glasses. Nothing visible.

The bore measurements make no sense unless you plug in poor machine work. Even if the barrel was bulged in the heat of battle the slug would still measure normal with a distorted rifling signature. I’ve seen that many times. That’s not what I’m seeing. What comes out is malformed. Yet you can’t see it with the naked eye. All I see is clear rifling all the way down. It’s amazing.

This truly was a desperate product. When I shot the rifle the report and recoil were normal. Shot placement at 50 yards was about 3 feet with like I mentioned, tumbling rounds, key holes often. Missing the target completely often. I shot 40 rounds that I match loaded.

It’s definitely not safe to shoot with such variance in bore diameter as low as .304 and as high as .319. I doubt the bullet actually spun. Oddest thing I’ve ever encountered.


Murph

"Last Ditch"...I imagine the state of rifle manufacturing in Japan at that time was pretty sketchy, thanks to US B-29's. Bullet exits the bore without blowing up the rifle, quality check complete.

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Hand tighten only

The markings translate to a late 1945 product from the Izawa Jyuko factory, short rifle with typical "last ditch" features. I'm not going any further with this. Have too many other projects going on but I found it very interesting. Also, I personally will never shoot a Last ditch Arisaka again. Only early war vintage. I don't care what the videos claim. I believe my shop tools. They have no opinion. They only measure what is true.

Murph

I’ve never heard of one that bad before. I’ve seen some that were in like new condition with bores that looked like they had thick chrome plating that made them look like Glock bores. I have a few 99s, all with chrome bores and with some you can’t really see sharp edge lands like conventional rifling. But if the action is in good shape it’s almost impossible to blow up a 99.

Back late 70’s many of my friends had either 38’s or 99’s which they brought out to the farm to shoot. One good friend dealt in jap items and had a last ditch he bought from a Veteran. Remember him shooting it at about 100 yds, didnt even hit the target. We all joked him. He also had a couple of 99’s that were very accurate.
Try and find a jap copy of the M-1 Garand to shoot, only seen 1 in a museum.

I think we are proving a pattern to the last ditch rifles. "UNSAFE", poorly machined.

BTW, I did not shoot full loads. I shot match loads but reduced loads. 139grain, and 170 grain, at 1800 and 1500FPS. That's one thing that I always follow. Using reduced loads on an unproven gun until proven safe. If I had slugged the bore I would have saved 40 match loaded rounds for a better gun. Also prevented possible injury from excessive pressure.

I took a look at the cases and some of the primers walked out. So there was some pressure issues as well. Obviously caused by the sectionally undersized bore. I'm at least glad I didn't load up full charges.

The actions on these are proven to be very strong, however case failure is known to injure shooters with gas blowing back at the shooters face. I guess I got lucky. I don't like that in the least. If I had been injured, I'd have nobody to blame but myself.


Murph

Your primers backing out were due to the low pressure of your handloads, not high pressure. What 139 gr bullets were you shooting? I am not aware of any 139 gr .311 or .312 bullets that are correct for the 7.7 ctg. The Arisaka action is very strong and also protects the shooter well in a case head failure. It’s basically a modified and simplified 98 Mauser. Did you scrub the bore well before shooting it? Could the difference in bore diameters be due to lead buildup from previous use of cast bullets?

I have never seen a "last ditch" rifle but then i've never looked for one. I have my grandfathers Type I rifle that was rechambered to 6.5X257 that shoots to POA if I use the proper bullets. 257 Roberts are not true 6.5 dia.

Of the 40 rounds I shot only 2 had primers that backed out.

I used Ideal/Lyman hard cast bullets. .311 cast at weights I listed.

You can actually see the oblong bore when you look closely. I missed it. Maybe because I’ve never seen one before.

Comparing an early war barrel to this last ditch reveals just how poorly it was constructed.

I’m not saying that “all” of them were junk. I’m just saying very clearly that this one is definitely poorly made. It’s not leaded up. It’s out of round. It’s not just the muzzle. It’s all the way! It was machined that way. If you had it in hand you can actually see it.

Murph

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I picked up a last ditch Kokura type 99 that was built probably in July 1945. Rougher exterior finish as expected and the front site is canted to the right. Shoots nice groups - but way left! Certainly a novelty.
Fp

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Well BMur your’s may truly be a very last ditch that gave all the late models their bad reputation. You could try a few handloads with medium power .311 150 jacketed bullets if you’re brave but it may just be a wall hanger.

I had a pristine, early war arisaka, that fit, form and function were nice...it was a calvary model. No comparison with WW2 late models. I ended up selling or trading--can't recall--due to ammo availability and pricing.

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Rather be outdoors

They have come up in value quite a bit. Especially with matching numbers etc. Even the "last ditch" examples are selling for a lot now. I have a matching early 6.5 carbine and early war type 99. This one isn't matching. Some parts are replaced.

I honestly see it as is a shooter, so I've decided to change the barrel out. I have a couple early war spares that are minty. If it was all matching, I'd leave it alone, but I want to take advantage of the functioning action. It functions extremely well. Feeds and ejects well. Trigger pull is perfect so it's going into the vice.

I sure hope the barrel threads are the same?

Murph

But is your mum intact?

It’s about 60% there. Looks like they tried to file it off but didn’t quite get there. No real impact in value with this one from changing the barrel out. It’s worth more parting it out.

Murph

Wondering if this is an example of something that some "gunsmith" tried to modify for some unknown reason over the years.

The Mums are partially ground on the majority of surplus Arisakas. The US military did that. Guns captured in battle usually had intact Mums.Guns surrendered at the end of the war usually had Mums that were quickly hit with a grinding wheel to keep track of which was which.It makes little difference in value unless the gun is otherwise mint. Of course on GB guns with Mums are hyped as rare collectors models and the sheep bid them up regardless of condition
.

Found one of those last ditch guns under a WWII vet neighbor's workbench about 50 years ago. Looked like a D- high school shop project. A few years later I bought my then-fiance a nicely sporterized 6.5. What a difference.

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I need ammo, not a ride.

Just a quick follow up to this thread. I did purchase an early war 7.7 short barrel rifle replacement barrel. It's in wonderful condition and will swap it out with the last ditch barrel that is out of round. Here is a photo of the slug that I ran through the barrel. It's amazing. Never seen anything like it. The bullet actually plowed through the bore without spinning. You can see how the lead actually scraped forward as the bullet was punched through. Believe it or not the exact same design bullet was used on each barrel. I'm still amazed every time I look at the results. Never heard of such a thing.

The second bullet is from the new barrel. Wonderful results.

Murph

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