Rechambering an arisaka type 38

Connor M. · July 26, 2021, 07:54 PM

I just picked up an early war arisaka type 38 and 375 ruger Barrel blank and I’m wondering if anyone here has tried rechambering one to this or a similar sized cartridge. -Thanks in advance, Connor.

**44 AMP** · July 26, 2021, 09:03 PM

I doubt anyone has tried that. I wouldn't think its a good idea.

The Type 38 Arisaka was chambered for the 6.5mm Arisaka round (6.5x50mm)
So, first off, I don't think a .375 Ruger round will fit. Its too long. Specs say loaded length of the .375 Ruger is the same as loaded length of the .30-06 round, and I think that's just too long to fit in the Type 38 action which is made for a round with a loaded length of 2.940"

It MIGHT work for length with a Type 99 action the 7,7mm Jap is max length at 3.150". I don't know if there is enough extra room there to allow the 3.340" length of the .375 Ruger, but I'm sure the room isn't there in a Type 38 action.

Second point even if it did fit for length, you'd need bolt face and receiver rail work to fit and feed the significantly fatter Ruger round, and last point,

According to Wiki, the 6.5 Jap is a slightly under 43000psi round.
The .375 Ruger is listed at 62,000psi.

Putting a round in a rifle that generates a third more pressure than what the rifle was built for is generally thought of as a BAD IDEA.

For a .375 Ruger, you need (at least) a .30-06 length action, either with or adaptable to a magnum size bolt face, and able to take 62,000 psi loads.

The Type 38 Arisaka does NOT meet any of those requirements, Sorry.

Geezerbiker · July 26, 2021, 09:18 PM

I think that a .250 Savage or 6.5 Creedmoor would be a better choice for that rifle.

Tony

taylorce1 · July 27, 2021, 06:41 PM

Quote:

Originally Posted by Connor M.

I just picked up an early war arisaka type 38 and 375 ruger Barrel blank

The .375 Ruger cartridge probably won't fit in your magazine as you've already been told. If you wanted a single shot bolt action you could probably make the action work. If your barrel is an .375 caliber blank that hasn't been chambered for the Ruger cartridge then you might have some options. A 6.5X50 overall length is 2.940" so you might be able to fit a cartridge like .375 JDJ 2.975" overall length in your magazine as there is only 0.035" difference.

Now that we found a cartridge that could possibly work, there are several issues to work out. The fist issue is who is going to do the work? There aren't very many gunsmith who will want to take on a job of sporterizing an Arisaka. You'll also be going to a rimmed cartridge so there will probably be feeding issues with the magazine and feed Rais to work out.

In the end it'll cost WAY more than just buying a rifle chambered in .375 Ruger. Your second best and cheapest option would be to purchase any modern bolt action rifle in 7mm Rem Mag or .300 Win Mag and have your barrel blank installed. I've messed with a few military sporter rifles over the years, no matter how cheaply you buy them, they just drain your wallet and your patience.

Scorch · July 27, 2021, 10:01 PM

Years back I had a Type 99 chambered in 6.5-06, and it was difficult getting that into the mag of the longer action. A Type 38 will be OK for 308 based cartridges, not something magnum length. A Type 99 would be a good bet. And, yeah, sporterizing military rifles is expensive. And Arisakas are a pain.

Jim Watson · July 27, 2021, 10:25 PM

A lot of T38s were rechambered to 6.5 x .257 Roberts, pretty much a 6.5x57.

So a 9.5x57 Mauser (.375 - 2 1/4" Express in England) should fit.

jetinteriorguy · July 28, 2021, 06:12 AM

Not to be rude, but just why would you do this?

**Mike Irwin** · July 28, 2021, 06:41 AM

The biggest problem with rebarreling an Arisaka is the metric threads that have never really been used anywhere but in Japan.

As I understand it there's no true English equivalent.

In order to use an English thread barrel, you'd likely need to bore the receiver and sleeve it...

The biggest problems with that course of action?

1. Arisaka receivers tend to be VERY hard.

2. Expense.

3. There may simply not be enough meat in the Arisaka's receiver ring to safely bore and sleeve it.

Gotta ask, though.. Why?

Of all of the WW II era rifles available for sporterization, the Arisaka is near, if not at the bottom, of the list in my opinion. It's a lot like the Moisin Nagant acxtions... crude, durable, workable, but with none of the finesse that would allow it to become a good sporting rifle.

Jim Watson · July 28, 2021, 08:13 AM

Right. This is one of those projects that would be an interesting challenge if you had the equipment and knowhow to do it yourself. The cost for a gunsmith makes it unfeasible.

Connor M. · July 28, 2021, 10:57 AM

I have the equipment to do it and I’m doing it for one of my school barrel and chambering projects. As for the why? I’m attempting it because nobody else has and I thought it could be kinda neat if it works out. It was already poorly sporterized when I purchased it so I don’t feel to bad about the notion of messing with a piece of history.

ernie8 · July 28, 2021, 01:42 PM

All the type 38 barrels I have measured have been right at 1 / 14 inch . A barrel threaded to 1 / 14 screws in well .

Jim Watson · July 28, 2021, 01:49 PM

Quote:

I’m doing it for one of my school barrel and chambering projects. As for the why? I’m attempting it because nobody else has and I thought it could be kinda neat if it works out.

If it doesn't work, do you flunk the course?

Quote:

It was already poorly sporterized when I purchased it so I don’t feel to bad about the notion of messing with a piece of history.

That's good.

**Mike Irwin** · July 28, 2021, 02:09 PM

OK, so that information makes quite a different.

We had no clue you were going to do the work yourself. We (or at least I) was assuming you were going to pay to have this done.

Ricklin · July 28, 2021, 03:41 PM

At the end of the day the other issues do remain, pressure being the dealbreaker.

Scorch · July 28, 2021, 05:05 PM

Pressure is not an issue. The Arisaka is one of the strongest actions made. PO Ackley tried to blow one up but failed. The big problems with them is there are no parts available and the design was so funky. For example: no way to rework the safety for scope use since it is part of the bolt and controls bolt operation, no aftermarket triggers available, things like that.

ernie8 · July 28, 2021, 06:02 PM

How would the original safety have a scope clearance problem ? Arisaka Triggers are very easy to work to whatever pull and weight you would like .

Scorch · July 28, 2021, 08:37 PM

I used to own a scoped Arisaka, the safety is a pain.
The Arisaka safety sits on the back of the bolt, you operate it by pushing and turning with the heel of the hand. If there's a scope in the way it's hard to get to.

Polishing military triggers seldom gives a good trigger pull. Timney used to make a trigger for the Arisaka, I doubt they still do.

Jim Watson · July 28, 2021, 08:52 PM

Still showing at Brownells, side safety included.

ernie8 · July 28, 2021, 09:12 PM

I work the safety with my thumb , no scope problem . The last match Arisaka I did had a 4 oz , no creep military trigger with 10 minutes work .

wachtelhund1 · July 29, 2021, 09:14 PM

I have an Arisaka 38 that I bought nine years ago with a nice Bishop stock on it. It had been sporterized. It was in the issued 6.5X50 caliber. I re-barreled it with a cheap Midway barrel and chambered it in 6.5X57 Mauser which I already had dies for. Also put a Timmey trigger w/thumb safety in it and had it blued. It is a very nice shooter. Several winters ago I checkered and refinished the stock.

jetinteriorguy · July 30, 2021, 08:09 AM

Ah, interesting. Good luck with it. Post picks if you will during the build and finished product.

reynolds357 · July 30, 2021, 09:09 AM

Quote:

Originally Posted by Connor M.

I just picked up an early war arisaka type 38 and 375 ruger Barrel blank and I’m wondering if anyone here has tried rechambering one to this or a similar sized cartridge. -Thanks in advance, Connor.

It's not practically doable and not safe, as has already been pointed out.
I can guarantee you that at the end of the project, you will say "I wish I had Spent $550 and bought the very nice 375 Ruger that Howa makes "

Jim Watson · July 30, 2021, 09:29 AM

It is a (gunsmithing?) school project.

Quote:

I’m doing it for one of my school barrel and chambering projects.

COTS is not an option.
I don't think the .375 R can be made to fit, but then I recall Ray Ordorica's article on a Mauser .416 Rigby.

**44 AMP** · July 30, 2021, 09:54 AM

Quote:

I’m doing it for one of my school barrel and chambering projects.

I'd talk with your instructor(s) and see if your grade will be entirely on the quality of your shop work, or if any part of it comes from the practicality and functionality of your conversion.

You can't make a working repeater using a .30-06 length round with a Type 38 action, unless you stretch the action to make it longer. You could make a single shot, but it might require removing the bolt in order to remove an unfired round. That functionally works, but its not a popular feature.

the way I see it, you're thinking of almost the equivalent of putting a V8 in a motorcycle. Technically, mechanically, it can be done. But, other than as an oddity, who would buy it? (and other than death daring thrill seekers -aka insane people- who would ride it??

)

If your project is, in any way going to have any part of your grade figured on anything but your machine work, you should probably rethink the combination of TYpe 38 and .375 Ruger.

However it goes, good luck!

Pumpkin · July 30, 2021, 10:15 AM

I have an old Type 99 that someone had rechambered to 30-06.
I had time, not much money and a machine shop and welder at my disposal.
My brother-in-law and I drilled and tapped it, it was very hard.
I cut the barrel to about 23" removed the rear sight, cut off, reshaped and welded the bolt handle back on. The problem was I used SS rod when Tig welding it. The pretty blue job did not like that!
I found a beautiful used Harry Lawson stock for next to nothing (who messes with an Arisaka), glass bedded the action, put a scope on it and loaded .311-.312 bullets for a 303 Brit in 30-06 cases with 30-06 dies. Not a hot load using IMR 4895 though it does seem to have some extra clearance close to the base looking at the fired brass. I used the brass one time and haven't shot it in 30 years.
The old gun shoots pretty good, safety is a bugger!

July 26, 2021, 07:54 PM	#1
Connor M. Junior Member Join Date: July 22, 2021 Location: Minnesota Posts: 2	Rechambering an arisaka type 38 I just picked up an early war arisaka type 38 and 375 ruger Barrel blank and I’m wondering if anyone here has tried rechambering one to this or a similar sized cartridge. -Thanks in advance, Connor.

July 26, 2021, 09:03 PM	#2
44 AMP Staff Join Date: March 11, 2006 Location: Upper US Posts: 28,821	I doubt anyone has tried that. I wouldn't think its a good idea. The Type 38 Arisaka was chambered for the 6.5mm Arisaka round (6.5x50mm) So, first off, I don't think a .375 Ruger round will fit. Its too long. Specs say loaded length of the .375 Ruger is the same as loaded length of the .30-06 round, and I think that's just too long to fit in the Type 38 action which is made for a round with a loaded length of 2.940" It MIGHT work for length with a Type 99 action the 7,7mm Jap is max length at 3.150". I don't know if there is enough extra room there to allow the 3.340" length of the .375 Ruger, but I'm sure the room isn't there in a Type 38 action. Second point even if it did fit for length, you'd need bolt face and receiver rail work to fit and feed the significantly fatter Ruger round, and last point, According to Wiki, the 6.5 Jap is a slightly under 43000psi round. The .375 Ruger is listed at 62,000psi. Putting a round in a rifle that generates a third more pressure than what the rifle was built for is generally thought of as a BAD IDEA. For a .375 Ruger, you need (at least) a .30-06 length action, either with or adaptable to a magnum size bolt face, and able to take 62,000 psi loads. The Type 38 Arisaka does NOT meet any of those requirements, Sorry. __________________ All else being equal (and it almost never is) bigger bullets tend to work better.

July 27, 2021, 10:01 PM	#5
Scorch Senior Member Join Date: February 13, 2006 Location: Washington state Posts: 15,248	Years back I had a Type 99 chambered in 6.5-06, and it was difficult getting that into the mag of the longer action. A Type 38 will be OK for 308 based cartridges, not something magnum length. A Type 99 would be a good bet. And, yeah, sporterizing military rifles is expensive. And Arisakas are a pain. __________________ Never try to educate someone who resists knowledge at all costs. But what do I know? Summit Arms Services

July 28, 2021, 06:41 AM	#8
Mike Irwin Staff Join Date: April 13, 2000 Location: Northern Virginia Posts: 41,383	The biggest problem with rebarreling an Arisaka is the metric threads that have never really been used anywhere but in Japan. As I understand it there's no true English equivalent. In order to use an English thread barrel, you'd likely need to bore the receiver and sleeve it... The biggest problems with that course of action? 1. Arisaka receivers tend to be VERY hard. 2. Expense. 3. There may simply not be enough meat in the Arisaka's receiver ring to safely bore and sleeve it. Gotta ask, though.. Why? Of all of the WW II era rifles available for sporterization, the Arisaka is near, if not at the bottom, of the list in my opinion. It's a lot like the Moisin Nagant acxtions... crude, durable, workable, but with none of the finesse that would allow it to become a good sporting rifle. __________________ "The gift which I am sending you is called a dog, and is in fact the most precious and valuable possession of mankind" -Theodorus Gaza Baby Jesus cries when the fat redneck doesn't have military-grade firepower.

July 28, 2021, 02:09 PM	#13
Mike Irwin Staff Join Date: April 13, 2000 Location: Northern Virginia Posts: 41,383	OK, so that information makes quite a different. We had no clue you were going to do the work yourself. We (or at least I) was assuming you were going to pay to have this done. __________________ "The gift which I am sending you is called a dog, and is in fact the most precious and valuable possession of mankind" -Theodorus Gaza Baby Jesus cries when the fat redneck doesn't have military-grade firepower.

July 26, 2021, 09:18 PM	#3
Geezerbiker Senior Member Join Date: March 20, 2011 Location: Willamina, OR Posts: 1,908	I think that a .250 Savage or 6.5 Creedmoor would be a better choice for that rifle. Tony

July 27, 2021, 10:25 PM	#6
Jim Watson Senior Member Join Date: October 25, 2001 Location: Alabama Posts: 18,539	A lot of T38s were rechambered to 6.5 x .257 Roberts, pretty much a 6.5x57. So a 9.5x57 Mauser (.375 - 2 1/4" Express in England) should fit.

July 28, 2021, 06:12 AM	#7
jetinteriorguy Senior Member Join Date: April 28, 2013 Posts: 3,173	Not to be rude, but just why would you do this?

July 28, 2021, 08:13 AM	#9
Jim Watson Senior Member Join Date: October 25, 2001 Location: Alabama Posts: 18,539	Right. This is one of those projects that would be an interesting challenge if you had the equipment and knowhow to do it yourself. The cost for a gunsmith makes it unfeasible.

July 28, 2021, 10:57 AM	#10
Connor M. Junior Member Join Date: July 22, 2021 Location: Minnesota Posts: 2	I have the equipment to do it and I’m doing it for one of my school barrel and chambering projects. As for the why? I’m attempting it because nobody else has and I thought it could be kinda neat if it works out. It was already poorly sporterized when I purchased it so I don’t feel to bad about the notion of messing with a piece of history.

July 28, 2021, 01:42 PM	#11
ernie8 Senior Member Join Date: October 9, 2018 Posts: 217	All the type 38 barrels I have measured have been right at 1 / 14 inch . A barrel threaded to 1 / 14 screws in well .

July 28, 2021, 03:41 PM	#14
Ricklin Senior Member Join Date: February 22, 2008 Location: SW Washington state Posts: 2,011	At the end of the day the other issues do remain, pressure being the dealbreaker. __________________ ricklin Freedom is not free

July 28, 2021, 05:05 PM	#15
Scorch Senior Member Join Date: February 13, 2006 Location: Washington state Posts: 15,248	Pressure is not an issue. The Arisaka is one of the strongest actions made. PO Ackley tried to blow one up but failed. The big problems with them is there are no parts available and the design was so funky. For example: no way to rework the safety for scope use since it is part of the bolt and controls bolt operation, no aftermarket triggers available, things like that. __________________ Never try to educate someone who resists knowledge at all costs. But what do I know? Summit Arms Services

July 28, 2021, 06:02 PM	#16
ernie8 Senior Member Join Date: October 9, 2018 Posts: 217	How would the original safety have a scope clearance problem ? Arisaka Triggers are very easy to work to whatever pull and weight you would like .

July 28, 2021, 08:37 PM	#17
Scorch Senior Member Join Date: February 13, 2006 Location: Washington state Posts: 15,248	I used to own a scoped Arisaka, the safety is a pain. The Arisaka safety sits on the back of the bolt, you operate it by pushing and turning with the heel of the hand. If there's a scope in the way it's hard to get to. Polishing military triggers seldom gives a good trigger pull. Timney used to make a trigger for the Arisaka, I doubt they still do. __________________ Never try to educate someone who resists knowledge at all costs. But what do I know? Summit Arms Services

July 28, 2021, 08:52 PM	#18
Jim Watson Senior Member Join Date: October 25, 2001 Location: Alabama Posts: 18,539	Still showing at Brownells, side safety included.

July 28, 2021, 09:12 PM	#19
ernie8 Senior Member Join Date: October 9, 2018 Posts: 217	I work the safety with my thumb , no scope problem . The last match Arisaka I did had a 4 oz , no creep military trigger with 10 minutes work .

July 30, 2021, 08:09 AM	#21
jetinteriorguy Senior Member Join Date: April 28, 2013 Posts: 3,173	Ah, interesting. Good luck with it. Post picks if you will during the build and finished product.

July 30, 2021, 10:15 AM	#25
Pumpkin Senior Member Join Date: October 18, 2020 Location: Seguin Texas Posts: 418	I have an old Type 99 that someone had rechambered to 30-06. I had time, not much money and a machine shop and welder at my disposal. My brother-in-law and I drilled and tapped it, it was very hard. I cut the barrel to about 23" removed the rear sight, cut off, reshaped and welded the bolt handle back on. The problem was I used SS rod when Tig welding it. The pretty blue job did not like that! I found a beautiful used Harry Lawson stock for next to nothing (who messes with an Arisaka), glass bedded the action, put a scope on it and loaded .311-.312 bullets for a 303 Brit in 30-06 cases with 30-06 dies. Not a hot load using IMR 4895 though it does seem to have some extra clearance close to the base looking at the fired brass. I used the brass one time and haven't shot it in 30 years. The old gun shoots pretty good, safety is a bugger!