Arisaka Type 99 Rebarrel

Scrambler96

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Hey,

I bought a sporterized Arisaka last year with the intentions of using it as the base for a future caliber conversion. I was thinking about having a custom 6.5 Creedmoor barrel made. I don't think feeding would be an issue since the cartridges seem very similar at the base? I'm guessing the different necking could have an effect on the feeding?

Not really worried about cost or practicality since I'm really partial to the Arisaka design, and not concerned about resale values.

Has anybody encountered rebarreled Arisakas? Scraping through old forum threads it seems most custom jobs were rechambers and people asking smart questions like if it's possible to shove a 308 into the chamber.

EDIT: Corrected misspelling of Creedmoor
 
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There's tons of converted Arisakas, however, the cartridge conversions were usually done in the 50s and 60s into things like 6.5-.257 Roberts or .30-06 or 7.62x39 in the case of the Arisakas left behind in the PRC.

There's a couple problems I see with converting a 7.7 to 6.5CM: (1) pressure differences; and (2) magazine feeding.

(1) Pressure

The SAAMI maximum pressure for 6.5CM is 62,000psi. There is no official SAAMI pressure for 7.7x58, however this article suggests that factory Norma ammo has a pressure of around 47,000psi:

Reloading Data 7.7x58mm Japanese Arisaka (Accurate Loading Guide #2) Metallic

Now, obviously not all 6.5CM ammo is loaded to max pressure, and the Norma 7.7 ammo is likely loaded slightly weak in deference to old guns, but there's clearly a difference in pressure between the two cartridges. By shooting warm to hot 6.5CM ammo through an Arisaka action, you're going to add wear on the gun that it wasn't designed to handle. Sure, we've all heard that Arisakas are supposed to be some of the toughest actions out there, but that doesn't detract from the fact that you'd be pushing an old receiver and bolt beyond what it was intended to handle. That'll cause problems on old guns, especially old guns made in a hurry during a war by potentially underskilled labor.

7.7x58 is basically a rimless version of .303 British. The .303 British was originally a black powder cartridge that was modernized into a smokeless one. Both 7.7 and .303 are pretty low pressure cartridges by modern standards. By upping the pressure, you're going to wear on the gun.

Instead, if you really want to convert a T99 into another cartridge, I'd try and stick with a similarly low pressure cartridge, like say 7.62x39. The Arisaka also isn't a long range gun by any means - it was designed, like all pre-WW1 designs, for volley fire at massed targets at known distances. Not sniping, not long range recreational shooting, not precision shooting.

(2) Magazine feeding

6.5CM is something of a short, fat cartridge, whereas 7.7x58 has a fairly tall and thin profile. I don't know, and I don't think anyone would really know, how well 6.5CM would feed from the Arisaka's original magazine. It would suck if you invest all this time, money, and effort into rebarreling an Arisaka, come to find out the gun doesn't feed for shit.
 
Hey,

I bought a sporterized Arisaka last year with the intentions of using it as the base for a future caliber conversion. I was thinking about having a custom 6.5 creedmore barrel made. I don't think feeding would be an issue since the cartridges seem very similar at the base? I'm guessing the different necking could have an effect on the feeding?

Not really worried about cost or practicality since I'm really partial to the Arisaka design, and not concerned about resale values.

Has anybody encountered rebarreled Arisakas? Scraping through old forum threads it seems most custom jobs were rechambers and people asking smart questions like if it's possible to shove a 308 into the chamber.
If I could find a new military contour barrel at a ok price I would have rebarreled one of mine already.
Pressure concerns aside for a moment.
You can get a idea if your 6.5 will feel in the 7.7 mag .
1. Does the 6.5 caee head fit the bolt head? If not is there enough meat on the head if it needs work?
2 load some 6.5 dummy rounds and see if they will fit the mag
 
If I could find a new military contour barrel at a ok price I would have rebarreled one of mine already.
Pressure concerns aside for a moment.
You can get a idea if your 6.5 will feel in the 7.7 mag .
1. Does the 6.5 caee head fit the bolt head? If not is there enough meat on the head if it needs work?
2 load some 6.5 dummy rounds and see if they will fit the mag

I was actually thinking about the bolt face issue myself yesterday because that was another concern I had besides pressure and feeding - both 6.5CM and 7.7 are 0.473" bolt faces.
 
I was actually thinking about the bolt face issue myself yesterday because that was another concern I had besides pressure and feeding - both 6.5CM and 7.7 are 0.473" bolt faces.
Thats one hurdle over come. Drop some dummy rounds in the mag and see if they will fit at your Expected COAL, then see if they will at least feed up and start into the chamber? I did a 308 conversion on my 98k and it works well if I just dont dilly dally on cycling , slow bolt manipulation will cause jams

who is going to do tour barrel work.
Do you know of other mauser type barrels that share same size barrel and threads? I have heard a few rumors over the years that win 70 barrels fit?

if it was not cost prohibitive I would love to send a type 99 barrel to a barrel maker and say copy this. Maybe even in 308?
 
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...
There's a couple problems I see with converting a 7.7 to 6.5CM: (1) pressure differences; and (2) magazine feeding.
...
Yep! I hadn't taken much consideration into pressures because the action is known to be capable to handle abuse from high pressure loads. But I agree with the fact there will be expedited wear on the action. I can't believe I didn't think of that. I was thinking 6.5 Creedmoor, but I'm not set on the particular caliber.
Thats one hurdle over come. Drop some dummy rounds in the mag and see if they will fit at your Expected COAL, then see if they will at least feed up and start into the chamber? ...
I was actually thinking about the bolt face issue myself yesterday because that was another concern I had besides pressure and feeding - both 6.5CM and 7.7 are 0.473" bolt faces.
I did notice base of 6.5 Creedmoor and 7.7J were the same. I'll 3d print a handful of 6.5 for testing how they sit in magazine and how the bolt picks them up. I can post my results at the end of next week.
who is going to do tour barrel work.
I was thinking about approaching Larry Racine, I haven't asked him yet since I don't want to bother him, especially since it's still tentative.
 
I'm not near a manual right now so I can't check pressures. As a possible alternative to the 6.5 Creedmoor, maybe the 6.5 Swedish Mauser would work.
 
I'm not near a manual right now so I can't check pressures. As a possible alternative to the 6.5 Creedmoor, maybe the 6.5 Swedish Mauser would work.

Pretty much any cartridge that uses a 0.473" bolt face would work in theory. He might even be able to rechamber it into .45ACP. The question is more "why?" Because converting to say 6.5x55 or 6.5x57 Mauser or 7x57 or .257 Roberts is going from one niche cartridge to another and doesn't provide much advantage over 7.7x58.

The reason why we see converted Arisakas usually is that people wanted cheap hunting rifles in the 50s and 60s and there was no surplus ammo. The guns were everywhere but ammo wasn't. The guns were also a lot younger - a 1945 Arisaka would've been five years old in 1950. So, converting one to .30-06 wouldn't be such a bad idea back then.

My personal take - leave the gun be and spend the money in a place where its needed more unless OP loves the gun for hunting and the bore is basically toast. And if the barrel was shot out, I'd probably either get a new 7.7x58 barrel or try and convert it to something super easy to find, like .223 or .30-06 or .308. Maybe 7x57.
 
Pretty much any cartridge that uses a 0.473" bolt face would work in theory. He might even be able to rechamber it into .45ACP. The question is more "why?" Because converting to say 6.5x55 or 6.5x57 Mauser or 7x57 or .257 Roberts is going from one niche cartridge to another and doesn't provide much advantage over 7.7x58.

The reason why we see converted Arisakas usually is that people wanted cheap hunting rifles in the 50s and 60s and there was no surplus ammo. The guns were everywhere but ammo wasn't. The guns were also a lot younger - a 1945 Arisaka would've been five years old in 1950. So, converting one to .30-06 wouldn't be such a bad idea back then.

My personal take - leave the gun be and spend the money in a place where its needed more unless OP loves the gun for hunting and the bore is basically toast. And if the barrel was shot out, I'd probably either get a new 7.7x58 barrel or try and convert it to something super easy to find, like .223 or .30-06 or .308. Maybe 7x57.
sometimes your no fun, lol
 
I decided to invest in reloading equipment, as much as it'd be neat to rebarrel the rifle, it isn't practical. My snap caps got lost in the mail system and I'm not going to spend another 20 bucks for a fanciful project. Thanks for all the replies, but at this point I think I won't be pursuing a rebarrel.
 
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