Forming brass for the 7.7 Jap

[GUTS]

I have a couple of Type 99s and decided that I would like to shoot them a little so I formed some brass. I run 30-06 brass through a 7.7 Jap FL sizing die and cut about a quarter inch off and trim. I used bullets I pulled from 7.62x54r.

30-06, 30-06 squeezed through 7.7 die, 30-06 squeezed and trimmed


Here's the trim die my machinist friend made for me.



The untrimmed squeezed 30-06.


I take most of it off with the bench grinder.


Then I file down to the die.


A quick spin on the deburr unit.


Over to the trim unit.


A final deburr and it's ready.


30-06, 30-06 fired case, 30-06 squeezed to 7.7, finished 7.7 case, loaded 7.7 shell

Information

Warning: This is a relatively older thread This discussion is older than 360 days. Some information contained in it may no longer be current.

[vintage hunter]

Nice job. I did practically the same thing to form 7.65 Argentine brass back in the day when the only factory brass available was the expensive and hard to find Norma stuff. I sized the first case in steps until the bolt would close with a bit of resistance and then set the locking ring. This way if theres a little bit of a headspace problem there won't be any case stretching on the first shot. I also anealed the necks to relieve any stress from working the brass. The majority of these cases are still being used today 22 years after forming them.

[GUTS]

It was suprisingly easy to size completely with one ram stroke. I use graphite powder in the necks, it seems to work.

[Parashooter]

Be prepared for some expansion. No harm as long as we keep pressures in the normal range.

[jmoore]

I also find it's best to anneal the necks after the rework. Mostly because of splits that form two or three years later. Sometimes on loaded rounds!

[MIKE33]

Nice post Good luck on the range

[Bruce McAskill]

Nice work on converting the 30-06 cases but as Parashooter said be ready for expansion near the case head and if your chambers are a bit over sized which is not uncommon with these rifles then you may only get the one firing out of them. If the surplus 7.62x54 bullets do not shoot well and they very well might not then switch over to the Hornady .314 diameter bullets and try those. Hope your cases work out for you.

[GUTS]

I shot ten rounds through one of my Arisaka 99s and the rifle liked the ammo. I was shooting offhand at steel from 100 to 200 meters and it shot where it was pointed. There are no signs of over-pressure. The widest part of the bases were right at .475" and the transition from the bulge to the base is very graduall.