[cardinarky]

My father was a Marine in the Pacific in WWII and was unfortunate to be in Hiroshima 6 weeks after the bomb dropped. Talk about PTSD! When he finally returned to the U,S. for the remainder of his life he never missed a day of work, but it took a 6 pack or more a night to keep him OK. I did not understand it then (I was born in late47) but I look at him as a saint now.
He passed away in 93 and I have learned more about him since he died, than I ever knew about him while he was alive. He was commander of the local American Legion Post 240 for 5 years, and worked 4 jobs, 1 full and three part time, to keep us going.
My son went to Afghanistan and Iraq this past decade, and that is where I really learned more about both of them. Why my dad did what he did and why my son (now a strong man) does what he does.

Anyway to my question: Dad found a warehouse in Hirshoima that had never issued model 99 Arisaka rifles. I was able to learn that this rifle was made in Chekloslovakia in 1938. When dad got home, he tried to get rid of everything that would remind him of the war. He gave the gun to my uncle, who had it sporterized to a 300 Savage.
When I inherited the gun, I wanted it in a military cartridge so the local Smith told me he could tap it to a 308 WCF. My question" can I load .311 bullets in the 308 brass and make a bullet that will have more accuracy than the arrangement I have now. The 308 going down the 311 barrel does not produce consistency.
I know this has been wordy but I wanted to somewhat introduce myself while explaining my dilemma.
Thanks for reading.

 

[GMFWoodchuck]

No, small bullets in big bores do not produce accuracy! LOL

If you're absolutely sure that it's a .311 bore then yes .311 bullets should work fine. You'll just need the right size expander for your dies.

You should, however, reconsider rechambering it. From what little I have read (in the 2 minutes after searching with google) you may find the the 300 Savage is more appropriate from a power and pressure standpoint in that rifle. I guess there were metallurgical issues towards the end of the war. You can just use .311 bullets in that using the same expander as I said earlier.

 

[cardinarky]

GFWoodchuck:
Thanks for the reply. The reason I changed from 300 Savage to 308 was military brass availibility. I was willing (30 years ago) to take an accuracy loss for ammunition in the bank. Now I think I will get some 311 bullets and try them with the expanded 308 neck..
Thanks again for commenting.

 

[Jack]

An Arisaka made in 1938 should be plenty strong. If you have worries about it, have a gunsmith look it over. If it was made in 1944, I'd be wary . .
You need a set of 308 dies (if you don't already have them) and a .311 expander button for the decapping stem. The die set won't have a big enough expander button, out of the box. A call to the die manufacturer should be all you need to get the right size button.
Then some .311 bullets, and you should be ready to start loading.

 

[MontyF]

Welcome to the site.

My first thought is if the 7.7mm Japanese barrel was chambered for the 300 Savage cartridge the shoulder would have been moved ahead about 3/8". Then I wondered if the barrel threads was chased to the new shoulder. Maybe the barrel was changed, I'd make sure the bore isn't .308 already. A trip to your smith is definately in order, IMO.

 

[broom_jm]

Have the bore slugged to make sure you're really working with a .311" bore, because little bullets in a bigger tube aren't accurate, but bigger bullets in a little tube...

I'm not sure why you'd want to change the existing barrel/chamber. The 300 Savage case is no slouch and works in a pressure window that you know the action will handle, even if it was one of the late-war rifles of questionable steel and workmanship. I guess what I'm saying is I'd go ahead and shoot it, as is, before throwing money at it to extend the chamber .144". With bullets up to 150 grains in weight, you'll be just as well off with the Savage case, anyway. FWIW, most of the Model 99 Arisaka rifles are very strong and can even take more pressure than the 308 dishes out, but why whip an old horse when you aren't sure what he's got left in the tank?

The original 7.7 Jap case works well and the 300 Savage is in the same operational window. Frankly, a lot of more seasoned hunters are figuring out that a little less speed often equals more reliable on-game performance, so stick with whatchya got and let us know how she shoots.

 

[oneoldsap]

You can make your .300-.311 Savage brass from surplus 7.62X51 (.308 Win ) brass . I know this from experience . Very interesting rifle , I too would stay with the lower pressure .300 Sav. Cartridge , to be on the safe side ! My Father was also a Pacific theater Jar-Head , 3rd Div. !