Tonight's project

[thughes]

Built a bunch of tacks for my Swedish hammer.....

[thughes]

And then proceeded to destroy 25 pieces of 7.7 Jap brass by running them through a 7.5 Swiss die (pushed the shoulder so far back they were not salvageable).

Note to self: Put your damn glasses on and make sure you're using the proper die........dumbass!

[24Pink14Stink]

Whoops.

[usmcveteran]

Those for CMP?

[thughes]

Whoops.

Yeah, especially when the unprimed Jap brass is almost .60/round.

[thughes]

Those for CMP?

[usmcveteran]

Everyone look out! Thughes is bringing his secret weapon!

[Figment]

Sorry for the brass loss, at least there is always the recycle bin to recoup some of the cost. I hate when I space out reloading. It's especially frustrating because you know it's critical you pay attention. I loaded a half dozen or more 9mm the other last week before I realized I hadn't changed the powder measure from when I was loading .40. Pulled them all of course and reloaded. Argh, felt like an idiot.

[WARFAB]

It's not possible to fire form the Jap brass shoulder back out to where you need it? I've seen other guys move the shoulder forward this way, but I don't know anything about the technical details.

[Tony]

as WARFAB stated, fireform... Reduce powder charge to suggested starting load then seat bullet to just engage rifling. This will hold case against bolt face and put your shoulder where it belongs.

[thughes]

Appreciate the suggestions on fire forming them. I thought about it but the shoulders are pushed back almost a quarter of an inch.....it would probably work fine but why take the chance on F'ing up a WW2 era collectible rifle (or worse, hurting myself) to salvage 15 bucks worth of brass? I still have @ 75 unfired cases so I'll save these bad cases for a rainy day and chalk it up as a learning experience. <sigh>

[dwa12479]

You should make a little necklace out of them, and wear it each time u sit at the press. That's your reloading dunce cap. Lol

[Tony]

A new fashion statement ...

[WARFAB]

I've read about fire forming, but the only time I've ever actually seen it done was when some old timer did it at the range while I was there. I can't remember what the parent cartridge was, but he was moving the shoulder forward substantially to create some Ackley Improved wildcats. I wouldn't be surprised if he was moving the shoulder a quarter inch or more based on my memory. He was also punching some impressively small groups at 100 yards while he was doing the fire forming. He was expecting some pretty crazy accuracy out of the finished cartridges.

I can understand your hesitation though. I'd be nervous about it as well and don't know enough about the process to attempt such a thing.

[Meketrefe]

You have several options to bring the brass to its original shape.
An easy way to do it is to simply expand the brass mouth to 358 caliber something that you can do in a 35 whelen die among many others and then run
it through the 7.7 arisaka FL die to create a temporary shoulder. Then load the case with varget up to the neck shoulder junction and then shoot
some 123gr bullets for the 7.62x39. If you don't have those bullets simply use a lower charge of around 85% density.
This will fireform the case and there is zero risk of malfunction. I would anneal those cases a little just because you push them so far so wen they expand
back they will not split defeating.

Another thing you can do is the suggested to jam the bullets against the lands that again with a 85% density will be totally safe. Either way you should measure
the case H2O capacity in order to calculate but something like Varget or R15 are very predictable just below the bullet base after seated.


Another way is to hydro form the cases with water. For this unless you have a hydro forming die you will need a regular die and a mandrel matching the diameter of
the case. If you have a lee expander that has a broken pin this could work great. Or even a shorter expander like a 308 winchester will do.
If the expander holder is flush and you can hit it with a rubber hammer that would work great otherwise you will need a quick change bushing for dies and a piece
of pipe that allows the die to go in but stops and the bushing. What we want to do is to fill the case with water all the way to to top and then start the case with a
couple of taps and with the case on a hardwood board the primer cannot escape so with a final good wack it will bring the die down and the water will push the shoulder.
This can be done too with an old press if you don't mind to get wet that you can always dry and oil again later. The thing is you need a fast moving jerk or blow
with lots of torque or in the case of the hammer some heavy mass along with it.

If you hammer on a flat surface or an old press you can find small flat head screw that you can put in the shell holder to prevent the primer to come out under pressure.
Hydroforming happens a lot sooner than the pressures necessary to ignite a cartrige but it has to be a decisive action.
If you do it on a board you might have a hard time bringing the brass out (Still oil the case) so you might need to thread the die with the case and the shellholer,
bring the ram up to hook it up to the ram and then extract the brass from the die.

Also you do not need the precise 7.7 but other calibers could do the same even if they are a bit longer shoulder. Just any other die that doesn't deform the base
but brings the shoulder up like a 30-06, 338-06, 280 or even 270 could be used for this if you have some lee dies and broken pin expander of any of those for
example. After that and the brass is dry with the shoulder back or even past the point of the 7.7 all is left is to oil the brass and this time run it with the actual
7.7. Also keep in mind that you can make pretty good 7.7 brass with once fired 30-06. you will need neck turning and annealing but it is not that hard to make.

Another option is save them and I will expand them for you sometime. I have all sort of dies and tools. LOL