Arisaka type 1 design questions

[tahunua001]

I don't own one but would like to some day. in the mean time I have a question about the design.

I know they are an amalgamation of Arisaka and Carcano design features built in italy for the Japanese navy but this is where the water gets murky. the Carcano is widely regarded to be one of the weakest actions of WWI/WWII era while arisakas are regarded to be among the strongest. given that the type 1 uses a carcano style bolt does this mean that it has a weak action or does the japanese meddling in the design somehow make it stronger?

also barrels. did the italians use their standard 268 diameter barrels and just shorten the chamber to take 6.5x50mm or did they actually make them in .264 diameter bores?

and as long as we discuss those topics, does the type 1 use progressive rifling or contrentric? also were they microgrooved like other japanese rifles or did they use standard italian grooves?

[Gunplummer]

There is no proof that the Carcano was a weak design. There is a rumor that special tool steel was used in the receivers and a royalty was paid to Chechezlovakia or Poland for the rights to it.The Type I was made to Japanese specs with Japanese inspectors at the factory. I will say that the chambers seemed a lot tighter on the Carcanos. I never really took notice whether the rifling was different or not.

[Mike Irwin]

Relatively speaking, compared to other contemporary guns, the Carcano action may have been weaker.

BUT...

It was MORE than strong enough to handle the pressures generated by the 6.5x52 Carcano round.

And, given that the 6.5x50 Arisaka round operates in pretty much the same pressure band as the Carcano, it becomes even less of an issue.

Unless you're going to rechamber your future Type 1 (or a Carcano) to the 150,000 PSI 6.5 Assblaster Nookulur Magnum, it's not an issue.

[Jim Watson]

It did not take long to search out an article about the Type I. By an Italian author at that. He does not give the barrel diameter but states:
"The barrel Carcano Arisaka is 2 cm shorter than the 1905 (38). It has a progressive rifling with four grooves of the Metford type, and this gave rise to manufacturing problems, but, once the process was fine tuned, accuracy and muzzle velocity exceeded the requirements."

Metford rifling is the rounded type commonly seen in Japanese produced rifles. No wonder it gave the Italians "manufacturing problems." I have to wonder if it is really progressive, or as we Colonials say, gain twist, like the 1891 Carcanos.

More at: http://www.exordinanza.net/schede/Type-I_eng.htm

You will find there that the action is straight Carcano, differing only in ejector placement.

[tahunua001]

Unless you're going to rechamber your future Type 1 (or a Carcano) to the 150,000 PSI 6.5 Assblaster Nookulur Magnum, it's not an issue.

________________

thanks for the info, you guys are all awesome.
oh mike you just got me wanting to watch tremors III again.

this is purely academic. if I ever get my hands on a type 1 it is staying in straight configuration. besides, 6.5 assblaster nukulur magnum is a pain to get dies for and reshaping the 50 BMG brass is a pain in the rear, or so I've heard

besides, I'm already set up to reload 6.5 jap. I know the 8 mauser conversions are widely regarded as unsafe to fire which is why I am concerned as my 6.5 loads are all pretty close to max since my shorty carbine has issues with terminal velocity but should I ever get one of these I really don't want to blow it up by shooting my hot loads meant for my carbine.

so they use the microgroove but still used progressive rifling? interesting concept to say the least. is there any real world advantage to such a design or was it just another way that italians made their guns 'special' like non standard bore diameters?

also another question. were the stocks 1 peice like carcanos or the two pieces glued together like japanese style stocks?

[44 AMP]

The reputation for Arisakas being among the strongest actions comes mostly from the blow up tests done by P.O. Ackley, and I believe what he was testing was type 99s and 38s.

Blow up tests are interesting, but often people only look at what it took to blow them up, and not that having an action that survives 20Kpsi more than another one doesn't reflect the max safe working pressure limits.

The Carcano action is, obviously adequate for the intended round. Even though I personally feel its a bit wonky working. I feel the same about the Moisin Nagant.

What Carcano's don't do as well as other designs is protect the shooter from gas if a case ruptures.

ALWAYS wear shooting glasses. Even if your rifle and ammo are in perfect condition. Because the one time you don't, is the one time they won't be, and might be the one time you'll need them.

[Jim Watson]

The article I linked discusses stock construction in some detail.

As to the progressive rifling, I would have to go after one with a tight patch on a swivel handle rod and see for myself.

Microgroove is Marlin's trademark for barrels with 12 to 20 shallow but distinct grooves. The Japanese rifles have four well rounded but deep grooves which is the Metford pattern given by the Italian author. Some look almost square at the muzzle.

[tahunua001]

ahh, I'd heard others talking about the metford grooves as nearly identical to arlins microgrooves so I just use the terms interchangeably now... I guess I should cure myself of that little habit.

[JT-AR-MG42]

I second Gunplummer.

I don't know the story behind the steel used, but most Type I actions that I have seen have had a plum/bronze color.

My Type I is by far the most accurate 6.5x50 I own. The chamber at the base is nice and round.
That concentric shape allows me to use .35 Remington cases - albeit a little short in the neck - so that I can use the Normas for the Japanese made 6.5s.

The stock on mine is two piece. Maybe birch?

JT

[James K]

First, the designation used by collectors is Type I (the letter, not the number one. (Note 1) The "I" seems to stand for "Italian"; the actual Japanese designation is not known, at least by me.

Perhaps some had regular twist Metford (Note 2) rifling, like the Japanese rifles, but mine has gain twist and appears to be the same rifling as other Italian rifles; it is not like the Japanese rifling. They were made by three different factories, but I think only one made barrels.

I did not slug the barrel, but I am sure the Italians were well aware of the caliber difference and would have made the barrels the proper diameter.

(1) The one collectors call the Type 1 (numeral one) is a Type 38 modified with a folding stock for paratroop use.

(2) Metford rifling is nothing like Marlin Microgroove rifling. Metford rifling, designed by an Englishman, William Metford, was intended to reduce fouling and to allow a barrel to be more easily cleaned. Its lands are rounded, not square cut as with most modern rifling. The British used it for a while, in rlfles designated, for that reason, as Lee-Metford rifles. The Japanese, who at that time were copying anything British, adopted it and never changed.

Jim

[tahunua001]

if that was the intention of metford rifling if definitely works in my type 44. after about 60 rounds down range I decided it was time for cleaning. the first patch came out a very light gray so I drenched the next patch with CLP, thinking that I just needed more than what was on the first and pushed it through. the thing came out nearly spotless, I was quite impressed with how clean it keeps itself.

I didn't know about the type 1 paratrooper. I knew about the type 99 takedowns that command a pretty high price and just recently found out about the ever so rare type 97 sniper that hope to god to own some day but my knowledge of arisakas is still admittedly in it's infancy.

yes I also was corrected just this morning that these are designated 'I' rather than '1'. I guess that was a clerical error of mine while reading about them for the first time.

[James K]

The Type I was yet another of Hitler's half-baked ideas. He thought the three Axis (Note 1) powers should help each other out and share industrial knowledge, ignoring the distance from Europe to East Asia (Der Führer flunked geography at Linz High School - he didn't really comprehend the size of Russia, either!)

The Japanese went along, though they had plenty of their own rifles and thought them superior to the Italian rifles, which is why the Army staff (which really ran the country) foisted the latter off on the Navy. Some were used by naval base guards and naval landing parties, which Americans, erroneously, called "Japanese Marines" (Japan had no Marines in the way the U.S. and Britain did).

The last batch of Type I rifles were shipped to Japan via the Trans-Siberian railroad just before WWII broke out (and while Hitler and Stalin were buddies, working on ways to carve up Poland).

One source says that Carcano bolts were used, which is not true; the bolts are not the same as Carcano bolts and are not interchangeable because the ejector slot is in a different place and the Type I bolt face is larger. The Type I also has an Arisaka/Mauser type magazine, loaded with standard Japanese clips, unlike the Carcano which, being a Mannlicher variant, is loaded with a 6-round en-bloc clip.

(1.) The term came from the pompous Mussolini. When he and Hitler signed the "Pact of Steel", he proclaimed that from that day forward the world would revolve around the new Rome-Berlin Axis. A bit of a wobble there, but then Benny wasn't big on physics. (Japan got tossed in later, and the world's axis got even more of a wobble.)

Jim

[Mike Irwin]

Metford rifling is also shallower than standard rifling.

As Jim says, the idea was to allow faster cleaning of black powder fouling.

Once the Lee Enfield switched from black powder to cordite, though, the higher pressure and much higher chamber pressures working against the softer steels available back then simply washed out the rifling for about the first 3 to 6 inches, ruining the barrel within a few hundred rounds.

[tahunua001]

The Type I also has an Arisaka/Mauser type magazine, loaded with standard Japanese clips, unlike the Carcano which, being a Mannlicher variant, is loaded with a 6-round en-bloc clip.

ahhh, i never even thought to ask if the type I could load from strippers or not. thanks Jim. that's a handy bit of info. that likely required further modification to the bolt face.

[Gunplummer]

I have seen a couple of those T-38's that were cut (Ugly jobs). Are you sure they were called Type 1? I sold a couple Type 2's at auction and am sure what they were called. I saw examples of what I thought were Type 1's, but never bought one. They were type 99 reworks with interrupted threads, or were they Type 100? They made quite a few, although they were considered experimental. Anyway, back to the type I, I had a couple that saw obvious use and one with the grease still in it. I actually saw quite a few over the years that looked in unissued condition. They must have been on the mainland, or did the Italians not deliver all of them?

[James K]

The ones called the Type 1 (one) Paratrooper rifle were just Type 38 carbines (19" barrel) modified with a hinge arrangement at the wrist; they did not come apart at the barrel/receiver interface like later ones including the Type 2. The "Type 1" rifles retained the normal Type 38 marking, unlike the Type 2, which was so marked.

The "Type 1" designation comes from Honeycutt; the gun is also called the Type 38 folding stock carbine. As with many other Japanese guns, the actual Japanese designation is not known.

Jim