6.5 Jap - 25 cal Jap
#2
The Japanese 6.5mm (.25 cal) weapons were all turn bolt operated, with 5-round non-detachable staggered row box magazines. They were loaded with 5-round stripper clips, a flat metal piece holding a five-round stack, which was inserted at the top of the magazine, the rounds thumbed down into position, and the metal piece sent flying when the bolt was closed.
#5
Nontypical Buck
Join Date: Feb 2003
Location: Michigan
Posts: 3,476
That's a new one on me. The 6.5 Jap round, as far as i know, is the 6.5 X 50 Arisaka cartridge, with a diameter of .264, a true 6.5 and not a 25 caliber (.257).
I'm not saying that there aren't Arisaka's with a "25" stamped on it, but I've seen hundreds of Arisaka's and have never seen one stamped "25". Maybe I haven't been looking very hard... ?
If aharely1 has fired 6.5 Arisaka ammo in this rifle then I'm guessing that it is a .264 bore.
Is your Arisaka 6.5 ammo factory loaded and clearly marked? I ask because of the following fact .....
A common wildcat for the Japanese Arisaka was the 6.5 X 257 Roberts, where the chamber was reamed out to the larger 257 Roberts capacity, then the cases were necked up to .264 from the .257 original size. Same could be done for the 7 X 57 case, but then you're necking down. And a slightly different shoulder angle. Actually a very nice round, but impractical today.
I'm not saying that there aren't Arisaka's with a "25" stamped on it, but I've seen hundreds of Arisaka's and have never seen one stamped "25". Maybe I haven't been looking very hard... ?
If aharely1 has fired 6.5 Arisaka ammo in this rifle then I'm guessing that it is a .264 bore.
Is your Arisaka 6.5 ammo factory loaded and clearly marked? I ask because of the following fact .....
A common wildcat for the Japanese Arisaka was the 6.5 X 257 Roberts, where the chamber was reamed out to the larger 257 Roberts capacity, then the cases were necked up to .264 from the .257 original size. Same could be done for the 7 X 57 case, but then you're necking down. And a slightly different shoulder angle. Actually a very nice round, but impractical today.
#7
Nontypical Buck
Join Date: Oct 2004
Posts: 1,085
8mm06... Interesting wildcat info...
I guess if I had a rifle so marked, I'd have a chamber casting made before sending a .264 bullet down what might be a .257 bore...
Considering the strength of the Arisaka action, ( Ackley regarded it as one of the strongest actions) it probably would not be an issue, , but why take chances..?...
The 6.5 x 50 was sometimes referred to as a " 25 caliber" ...
I remember reading " Guadalcanal Diary" where the author described the lighter report of the " 25 caliber " Jap rifles compared to the heavier report of the Marine's .30 cal rifles..
I guess if I had a rifle so marked, I'd have a chamber casting made before sending a .264 bullet down what might be a .257 bore...
Considering the strength of the Arisaka action, ( Ackley regarded it as one of the strongest actions) it probably would not be an issue, , but why take chances..?...
The 6.5 x 50 was sometimes referred to as a " 25 caliber" ...
I remember reading " Guadalcanal Diary" where the author described the lighter report of the " 25 caliber " Jap rifles compared to the heavier report of the Marine's .30 cal rifles..
#8
Nontypical Buck
Join Date: Feb 2003
Location: Michigan
Posts: 3,476
I've never hear it before, not from my grandfather or anyone else ..... I'm sure it's true, as many wrong labels get used .... and while I don't doubt the authenticity of the nomenclature being used, it is still wrong, as no Japanese Arisaka was ever produced with a 25 caliber bore. They may have been labeled or called that, but I'm mighty sure you won't be able to find a record of any Japanese weapon from 1900 on using a round of .257 diameter.
In all fairness though we're talking about a difference of .007 between the 6.5 and the 25 caliber, so I guess I'm just a stickler.
And Pygmy is right about the Arisaka's strength as proved by Ackley. I read that he repeatedly tried to blow up the Arisaka action by shooting 30/06 through the 6.5 rifle ... That's right... he repeatedly fired the 30/06 ammo until the barrel was sent down range with no apparent damage to the action except for the threads being toast. If i can find the link I'll post it.
I was never aware of a common use of misnaming the 6.5 X 50 as "25" caliber ... You learn something new all the time.
And while we're at this topic, we would be remiss if we didn't acknowledge that this kind of number misnaming goes on all the time with firearms. I'll bet we could fill a book with the long list of misnamed calibers, diameters, etc that fill the gun world with opportunities for confusion.
That's what makes it a hoot to try to stay focused on the myriad of facts and tidbits in the firearms industry and history.
Last edited by 8mm/06; 01-09-2010 at 07:52 AM.
#9
Nontypical Buck
Join Date: Feb 2003
Location: Michigan
Posts: 3,476
Here's at least one mention of Ackley testing the Arisaka and being impressed. The article below mentions rechambering the 6.5 chamber to 30-06 and firing it down the 264 bore ...
doesn't mention the "barrel downrange" part I referenced .. and maybe that's an exaggeration, but a good article to peruse anyway
http://findarticles.com/p/articles/m.../ai_114283920/
doesn't mention the "barrel downrange" part I referenced .. and maybe that's an exaggeration, but a good article to peruse anyway
http://findarticles.com/p/articles/m.../ai_114283920/
#10
Nontypical Buck
Join Date: Oct 2004
Posts: 1,085
Thanks for the link...Interesting reading...I've always had an interest in WWII military rifles, perhaps partly because my Dad served in the South Pacific in WWII...
I currently own both a type 38 and a type 99... I have them on display at my local American Legion post along with a K98K ( 1938 Oberndorf)Mauser... The type 99 sports a bayonet that my Dad brought home from the war.. The rifle itself was liberated and brought home by a merchant marine sailor..
I currently own both a type 38 and a type 99... I have them on display at my local American Legion post along with a K98K ( 1938 Oberndorf)Mauser... The type 99 sports a bayonet that my Dad brought home from the war.. The rifle itself was liberated and brought home by a merchant marine sailor..