.30-06 in a 6.5 Jap.

[351 WINCHESTER]

This is to clarify a post I did the other day. Some one reamed the chamber out of a 6.5 Jap. rifle as someone told him he could shoot .30-06 rounds thru it. He did shoot it and took it to a gunsmith to try and find out why it was kicking so much. Instead of using the 6.5 he was supposed to use the 7.7.

Can anyone imagine the pressure generated by firing the .30-06 in a 6.5 bbl?

A good friend told me that story and subsequent efforts of trying to blow up the rifle. He loaded a lot of pistol powder, tied it off to a tire and got behind a tree while pulling the trigger. I don't know how many times he tried to blow the action, but it held, although he said the bolt was kinda stiff.

This rifle is in a museum somewhere in the States as a testiment to the great strenght of it's action. It's too bad that someone didn't try and find out the steel they were using and how they were heat treating it.

Just thought I'd try and clear up my previous post.

 

[.45Guy]

Sounds like P.O. Ackley and his experiments. Although he rebarelled to his Ackley Improved cartridges and loaded as hot as he could. The Arisaka was #1 in his tests.

 

[Jim Watson]

The Arisaka of legend is at NRA HQ. I do not know if it is on museum display.

How would shooting 7.7 down a 6.5 barrel have been any different from .30?

P.O. Ackley said that the bullet was sized down to fit the barrel by the time it moved its own length, and before chamber pressure reached maximum, therefore an oversize bullet contributed little to excess pressure. The key being that the chamber was correct so the brass sealed the chamber and the neck could expand to release the bullet. Seems that bullet "pinch" in a tight neck is about the only thing that will give pause to the intrepid experimenter known now as Clark.

 

[Jeff F]

Jim, I think they were supposed to start out with a 7.7 and ream the chamber of that to 30-06. I've herd of it but never seen it done.

 

[Jim Watson]

That could be done. I don't know if the longer OAL of .30-06 would fit the magazine. And modern day Internet Pantywaists get upset over the slop in the chamber and the attendant casehead expansion, even though there were several bargeloads of 7.7 reformed from .30-06 in the day. The period method of getting US factory ammunition in a 7.7 Jap back when surplus rifles were cheap (or souvenirs from having been shot at with them) and gunsmiths worked cheaper, was to set the barrel back and chamber for .300 Savage.

But there really was a 6.5 rechambered to .30-06 without the formality of reboring from .264" to .308" and it really did shoot without blowing up. . Kicked, though. The NRA has it now.

 

[Sunray]

"...start out with a 7.7 and ream..." The .30-06's .308" bullet would rattle down the .311" barrel. It wouldn't bother the rifle though. Arisakas were reputedly the strongest bolt actions used by anybody in W.W. II.
"...I've herd..." Mooo!!!

 

[Essex County]

Back about fifty years ago, it was not rare to see 7.7's converted to .300 Savage. I assume the barrels were set back and folks handloaded .311 bullets. It was a way of getting a bolt deer rifle cheaper than buying a new Remchester......Essex

 

[Carl N. Brown]

I have seen a couple of 7.7mm Arisakas rechambered to .30-06.
It was a fairly common "sporter" conversion in East TN and
Southwest VA in the 1950s and 1960s. (Worked better if you
reloaded with .311 bullets made for the .303 Brit.) Rechambering
7.7 Jap to .30-06 is not new. Rechambering 6.5 Jap to .30-06