Ok so I was perusing a local pawnshop, a junky place where only the best stolen items are sold (or so it seems in our county there is where most it seems to end up), and they had a half-way converted Jap 7.7 Arisaka, and it appeared that whoever had it last had set the barrel back a full turn and then rechambered to 30-06, as it was the service barrel (with a gap in the stock from setting it back).

OK, so here is my question - I thought that 7.7 Jap was about .311 in diameter? If you do that, will the gun be in any way accurate with factory ammo?

It was common after WWII when a lot of 8mm's were brought back to the states to run a 30-06 reamer in and leave the barrel alone. I had one I paid $25 for and killed two elk with it. The 7.7 is .303 (7.7 x .03937) The 8 mm is .315. The 8mm would work, but the 7.7 is smaller. Maybe with cast bullets

I made a .270 out of an Arisaka. I bought a barrel from Numerich for $60, turned down and threaded it. Couldn't do much about that big knob on the back for a safety though. I D&T'ed it for scope mounts, bent the bolt handle. I killed a nice Big Horn Sheep ram with it on Pikes Peak about 350 yards. My niece ended up with it for her 1st deer rifle.

No it won't be accurate with factory 30-06 ammo , hell they ain't very accurate in the original chambering.

BTW if it is as you describe then it ain't a 30-06 , it's a 311-06 or 7.7-06


Mike

I'd definitely do a chamber cast to be sure of the dimensions. It may shoot factory 30-06 fine, but then it may not.

The US Army rechambered a bunch of Arisakas for use in the ROK Army until they could get them all equipped with M1s and M1 Carbines immediately after WWII. They weren't used for long, but they did do it.


An uncle of mine had a rifle such as the OP described, but he claimed it shot "okay" by using .311" bullets in '06 cases.

They work, for the purpose, even GI Ball ammo worked well enough for the government's purposes.

that is what I was driving towards, or trying to say - thanks all!

My old fart hunting buddy, has killed at least a hundred or more deer with 7.7 Jap in the original form. He bent the bolt, scoped it, whittled a little on the stock. It is plenty accurate.

Jack

I hunted preds with 7.7 ball ammo in the 1960s. The Ariska was sporterized and had a receiver sight and ramp front, it was more than accurate for fox to 200 yards.

You can change out the expander ball on your 30 06 die to a .310 and use .311 or .312 bullets.

8mm bullets come in two diameters .318 for the original 8mm Mauser rifle and later sporting rifles and the .323 bullet was adopted in the military rifles around 1900 and sporting rifles after WW-II.

That might be a good 338-06 re-bore.

Some .303 British rifles will shoot some .308 bullets quite accurately, and quite a few 7.65 1909 Mausers were rechambered to .30-06 and shot at least OK. One of my old hunting buddies bought a rechambered (and "sporterized") 7.65 when he was in high school in the 1950's, and hunted his whole life with it, killing a pile of antelope, deer and elk. He handloaded whatever .30-caliber 180's were cheapest down at the local store.

In my experience a lot depends on the bore (not groove) dimension. If it's no more than .302" or so, it might work. Also, I've seen more than one .303 that would shoot Nosler Partitions pretty well, probably because the rear core "bumps up" with a typical .303 charge of medium-rate powder.

There are quite a few Arisakas out there that have been rechambered to 30-06. Also see Lee Enfields in 308,and Mauser
1909s converted from 7.65x53mm to 30-06. Reload with .311 diameter bullets and you should be fine. Timney makes an after market safety for Arisakas, one of the guys here sold me one for my Type 38 carbine, but I havent gotten around to getting it done.

I found one at an estate sale, complete with a bayonet in a wooden scabbard. The bore was fouled so bad you couldn't see what the rifling was like. This was probably one of the ROK guns as the Chrysanthemum was defaced, and the 30-06 marking was faint. Minimum bid was $225, now I sorta wish a had bit. The original bayonet is probably worth more than the rifle. After seeing that, I did a bit of research and learned about the ROK guns. The twist in a 7.7 is 1 in 9 1/2 so the 06 apparently did not like it along with the oversize bore.

PS the 99's that were made before the final push were hell for stout; one account I read of testing actions had the barrel give way before the receiver. War production was anything that came off the line at the end.

Like Muledeer said, some rifles with .311 bores do shoot .308 bullets just fine. I had a .303 SMLE that was very accurate with plain vanilla cup and core .30 caliber bullets. If you wound up with that rifle it would be worth a try.

Arisaka rifles made during the pre and early war years are high quality guns. Most have chrome plated bores. The sights and some of the gadgets such as the monopod and anti-aircraft wing sights can be a bit wacky but they are strong actions manufactured to a high standard.

Of course the "last ditch" rifles are a different story.

IIRC it was P. O. Ackley who wrote about testing a Mauser, a Springfield, an Enfield, and an Arisaka in blowup tests. The last one to let go was the Arisaka. I don't remember if it was a type 38 or a type 99.

I have a 7.7 "Jap" that was brought back from Korea by a cousin. He passed away way too young from heart disease and the rifle was passed to me.

Chambered for 308, bolt handle bent and a pretty walnut sporter stock. Just the original peep sight. Don't know the details of the gunsmithing involved, but it's accurate as far as one wants to shoot with open sights.

Ackley described testing three different 6.5x50 Arisaka actions.
--Bob

Do you remember if he ever wrote about testing a type 99 action?

J_S-
My rememberer has had functional difficulties lately, so I checked my library before writing this answer.

Ackley published his report in the 156-page 1959 edition of his Handbook for Shooters & Reloaders, and then again in Volume 2 of the expanded 1962 version of the Handbook.

Ackley "tested" three 6.5mm Arisaka M38 rifles., one 7.7mm Arisaka M99 rifle, and two 6.5mm rifles with "cast" receivers.
One of the latter was fitted with a bolt from an M99.

For all the tests, Ackley rebarreled the actions for his .270 Ackley Magnum cartridge, which in his photos is just a smidge smaller than the .270 Weatherby.

The two cast actions came apart with "normal" loads for his .270 Ackley Magnum cartridge. The 6.5mm M38 actions held together despite overloads that split the barrels. The receiver of the 7.7mm M99 ruptured with a heavy overload. Ackley rated the strength of the M99 action just below the M38, but better than any of the other military action he tested.

--Bob

Thanks for the info. My rememberer doesn't work so well, either.

I have a Type 99 rechambered to 300 Savage. It shoots better with .311 bullets but will handle .308 bullets if need be. Accuracy of both will handle most hunting needs considering it wears a peep sight.

I have two arisaka's 7.7 rifles brought back at the end of WWII by a relative. One still has not been fired, the other one has.
I also had about 40 rounds of ammo, that has been around since that time. I never looked at it much until about a year ago, then found something i thought interesting. The brass was U.S. m2ball brass for 30.06 redone to the 7.7 arisaka.
I guess i am going to have to pull a couple out and mike the bullets. for diameter.