Reloading 7.7 Japanese

[TruthTellers]

Owning an Arisaka has been on my mind recently, mainly because I think it's one of the last good deals for milsurp rifles out there. The only prohibitive aspect of it is of course the rarity of the ammo and it's price.

So, because I don't want to cut off the prospect of the Arisaka, I want to know about reloading for it. I've read that .30-06 cases can be case formed into the 7.7 Jap. Currently my two presses are Lee's: the hand press and the Classic Turret.

I don't think either could do any case forming. If I were to do case forming, I assume I'll need a cast iron single stage press, yes? Could an Aluminum Lee "0" frame do it?

Then, what bullets could be used for the 7.7? Have any Arisaka owners here found a particular bullet the rifles like?

[FrankenMauser]

Your turret press could get the job done. ...Or even the hand press, if you're feeling froggy. There isn't much brass being pushed around.
No new press would be necessary.

Many 7.7x58 Jap shooters have found, like 7.62x54R and .303 Brit shooters, that the Hornady 174 gr RN is the bee's knees...
Those in my family follow that stereotype, and I expect my upcoming 7.7x58 Jap build/resurrection to follow suit.

[TruthTellers]

Would I have to anneal the cases so they don't crack from the stress being built up or could I just buy brand new .30-06 brass and form them right out of the box?

[44 AMP]

I've made about a hundred or so 7.7mm from GI .30-06 (LC 53), never annealed anything, never lost a case to cracking. The difference between the two cases is about .224" over all length and about .13" in case body length.

The 06 rim is .003" larger than the 7.7mm (by the specs actual cases vary), but that small amount of rim difference doesn't seem to matter to the Mauser type extractor of the Arisaka. Case head dimenions are .470" for the 06 and .471" for the jap, so it works ok.

If I remember right (its been some years) I trimmed about .2" from the 06 case then run it through the 7.7 sizer die. I don't know about a turret press but any good C or O frame will do it just fine.

Cases can be a few thousandths short, it doesn't hurt function.

I have gotten commercial 7.7mm from Graf & Sons, and at gunshows, though not lately, I have enough, so I stopped looking, and stopped converting 06 brass.

Buying new commercial 06 cases to convert is a waste of money, but its your money.

Hope this helps.

[F. Guffey]

I shooter west of Ft. Worth, TX wanted to shoot his 7.7; I contacted him to get his mailing address, later I met him at the Market Hall gun show. Anyhow, I formed 80 cases in 4 sizes, I formed 20 that were minimum length, I formed 20 that were go-gage length, I formed 20 that were no go-gage length and then I formed 20 that were field reject length.

He loaded the minimum length sized cases and the go-gage length cases and headed for the range. He attempted to load the no go-gage length cases but could not close the bolt on them. Whole at the gun show I introduced him to resource people.

On the cases that would not chamber I suggested he size to minimum length and then trim.

F. Guffey

[T. O'Heir]

The 7.7 Jap uses .311" bullets just like .303 Brit(if its barrel uses that diameter) or 7.62 x 54R.
Midway lists over priced Norma ammo(it's always been expensive) and reasonably priced Prvi brass. $43.99 per 20 and $28.99 per 50 respectively.
Graf's list PCI ammo as well as Norma. $28.99 per 20 for PCI 150 grain SP's. Out of stock for the Norma and PCI 174 grain ammo.
This data came out of my old Lyman book.
Bullet diameter cast and jacketed: .311" or .312".(Barrels need slugging.)
Max Case Length: 2.269"
Trim-to: 2.260"
Max OAL w. bullet: 3.150"

150 grain Jacketed
Powder Start Vel Max Vel
IMR3031 42.0 2444 46.0 2717
IMR4895 43.0 2386 48.0 2754
IMR4064 43.0 2267 48.0 2666
IMR4320 45.0 2421 49.0 2717
IMR4350 49.0 2304 54.0 2659
H380 47.0 2375 52.0 2695

Accuracy Load: 43.0 grains IMR4064 2267 fps.

180 Grain Jacketed
Powder Start Vel Max Vel
IMR3031 39.0 2202 43.0 2444
IMR4895 42.0 2304 46.0 2564
IMR4064 42.0 2227 46.0 2512
IMR4320 43.0 2302 47.0 2590
IMR4350 47.0 2207 51.0* 2538
H380 45.0 2237 50.0 2525

Accuracy Load: 47.0 grains IMR4350 2207 fps
Factory duplication Load: 44.8 IMR4895 2500 fps.
'*' indicates a compressed load.

215 grain Jacketed(Woodleigh makes 'em. Midway sells 'em.)
Powder Start Vel Max Vel
IMR3031 35.0 1992 39.0 2178
IMR4895 39.0 2127 43.0 2352
IMR4064 39.0 2053 43.0 2293
IMR4320 41.0 2178 44.0 2347
H380 43.0 2123 48.0 2352

Accuracy Load: 49.0 grains IMR4350 2375 fps.
Factory Duplication Load: 40.0 IMR4895 2197 fps.

155 grain Cast w. Gas Check
Lyman mold #311466 #2 alloy
Powder Start Vel Max Vel
Unique 11.0 1470 15.0 1739
2400 22.0 1821 24.0 1953

205 grain Cast w. Gas Check
Lyman mold #311299 #2 alloy
Powder Start Vel Max Vel
Unique 10.0 1250 14.0 1524
2400 21.0 1607 24.0 1792
IMR4227 28.0 1923 30.0 2049

213/214 grain Cast w. Gas Check
Lyman molds #311290 and #311284 respectively(Montana Bullet Co makes the 213 at least)
Powder Start Vel Max Vel
Unique 10.0 1214 13.0 1423
2400 21.0 1595 24.0 1739
IMR4227 28.0 1865 30.0 1992

Accuracy Load: 30.0 grains IMR4227 1992 fps.

[FrankenMauser]

Annealing would be helpful, but not necessary. But...
I'm glad 44 AMP brought up what I forgot to say:
Just buy brass -- Hornady (if they're still making it) or PPU, and forget about forming.

[TruthTellers]

I only bring up the .30-06 brass because I can find that stuff in the gun store 5 mins from me or when it goes on sale I can get it for a low price. If it's not that high stress of a case forming application, then I'll look at getting the Aluminum Lee Challenger press or the cast iron one.

Which brings me to a new question: What type of case forming would require using a cast iron press instead of an aluminum press? I ask because if I get into more strenuous case forming activities in my life, I'd like to know I bought an O frame press that can do the job.

[FrankenMauser]

Short of swaging case heads, or working with something like .50 BMG, I don't think there's any reason to worry about the Lee Challenger, if that's what you want.
Most case forming processes take no more effort than sizing large cartridges (8x57, '06, etc.) that were fired in an over-sized chamber.

The most effort that I can recall while case forming something useful (not just a ridiculous experiment), was .577-450 from 24 ga brass shot shells.
The process starts by forming a shoulder on a .58 caliber straight-walled case, and rolling that in to form a neck for a .45 caliber bullet.
And then that shoulder gets 'rolled' (pushed) on down the case quite a bit, while the material moves through the shoulder and into the neck.
Lots of effort to start it.
Plenty of effort to keep it going (even if just a little bump at a time).

I think even the Lee Reloader press, possibly even the hand press, could do the job. ...If they were able to accept the dies, that is. My .577-450 dies are threaded 1-1/4"-12, and can only be used in a press with a removable 7/8"-14 adapter.



I'll tell you flat-out that if/when my 7.7 project gets running, I'll be using brass formed from '06. ...But not because I don't want to pay for PPU brass.
It's because my grandfather set the shoulder back too far on about 800 pieces of primed .30-06 about 20-25 years ago. Since then, we've been forming and trimming that brass to 7.7x58mm Jap, simply because it's available (and free!). Most of the cases fail (shoulder/neck cracks) after just 2-3 firings, but they have not been annealed and had already seen many reloadings before getting the shoulders bumped too far.

[F. Guffey]

Which brings me to a new question: What type of case forming would require using a cast iron press instead of an aluminum press?

I have the Dillon 550B, I do not form cases with it, I have the RCBS Pardoner press, I do not use it but I have it JIC. After that any press I use is cast Iron, most are the 'C' type with the exception of my 2 ram Herter and the 'U' Herter. And then there are the 'O's.

I know, there is an illusion about the strength of presses, I have feeler gages, tension gages, deflection gages and the gage that measure strain, I do not have a King Kong press. Presses were tested and rated in the old days, 'C' type presses that flexed when under a heavy load were modified or had modifications that were available; the modification turned the 'C' press into an 'O' press.

And then there is case lube.

F. Guffey

[TruthTellers]

Originally Posted by FrankenMauser

Short of swaging case heads, or working with something like .50 BMG, I don't think there's any reason to worry about the Lee Challenger, if that's what you want.
Most case forming processes take no more effort than sizing large cartridges (8x57, '06, etc.) that were fired in an over-sized chamber.

The most effort that I can recall while case forming something useful (not just a ridiculous experiment), was .577-450 from 24 ga brass shot shells.
The process starts by forming a shoulder on a .58 caliber straight-walled case, and rolling that in to form a neck for a .45 caliber bullet.
And then that shoulder gets 'rolled' (pushed) on down the case quite a bit, while the material moves through the shoulder and into the neck.
Lots of effort to start it.
Plenty of effort to keep it going (even if just a little bump at a time).

I think even the Lee Reloader press, possibly even the hand press, could do the job. ...If they were able to accept the dies, that is. My .577-450 dies are threaded 1-1/4"-12, and can only be used in a press with a removable 7/8"-14 adapter.



I'll tell you flat-out that if/when my 7.7 project gets running, I'll be using brass formed from '06. ...But not because I don't want to pay for PPU brass.
It's because my grandfather set the shoulder back too far on about 800 pieces of primed .30-06 about 20-25 years ago. Since then, we've been forming and trimming that brass to 7.7x58mm Jap, simply because it's available (and free!). Most of the cases fail (shoulder/neck cracks) after just 2-3 firings, but they have not been annealed and had already seen many reloadings before getting the shoulders bumped too far.

Good thing you mentioned .577 cases because I do have on my mind reloading .577 Snider and I'd need a single stage with the larger diameter threads to install the dies. I've also thought about doing .577/450, but the amount of time and difficulty reloading for the Martini-Henry isn't really something I want to do, but I do have an interest in the Snider and Martini-Henry rifles.

They're just not on my gotta have now list.

[T. O'Heir]

Have a how-to for making .577/450 cases out of 3/4" brass bar stock if either of you want it. Basically makes it into a .45-70 by means of a reloadable chamber insert.