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atl5029
07-24-2015, 03:56 PM
Hi yall,

I am in the process of building a 260 AI rifle, and I have been pondering how I can fire form brass, get some trigger time, but not waste barrel life fire forming brass. I was thinking a good solution would be to fire form the cases using a GC cast boolit. I also have a canister of pull down powder from Bulgarian heavy ball 7.62x54r. I have used this powder to load new x54r brass with new bullets using starting charges and working up in small increments. The powder seems to be in the 4064 - 4895 range. I was thinking about starting with a 30-31 grain charge and a 135 grain cast GC bullet to fire form my brass. Any thoughts?

Anyone know what pressure is needed to fire form brass?

Thanks!

GRUMPA
07-24-2015, 05:04 PM
Since I convert more cases into something else here's my scoop. I can't afford to get this and that for what I do, sooooo off to the information super highway I go (AKA Internet). After reading up on Hydroforming a bit.....it sounded pretty good and there really wasn't a need to fire form converted cases like there once was.

The reviews they gave on Hydroforming really got a person hooked on the idea, that is.....till you got to the bottom of the page and read what they charge for those little jewels. Now steps in the Frugal....AKA Tight ***....and now your talking my language. You couldn't get a dime dislodged from my nether regions with a 4x4 tractor....but that's another story.

You can do it on your own providing you can get access to a lathe, or know a machinist, it's easier than you think actually.

Remove the de-capping rod from the sizing die.
Find something short that will thread in the die that the de-capping rod screwed into.
size the brass and get a measurement of the I.D. of the neck and machine a grade 8 bolt down to size. You want a tight fit since you don't want water just flying out or past the rod when you whack it with a hammer.
Whatever size you take that rod to make a hole in whatever it was you have that screws into the die.002 bigger than the rod.
Make a plug for the shell holder, you need to do this with a primer in the case. And you'll send that primer to the next county if you didn't plug up that hole in the shell holder.

Normally it'll only take 2-3 good whacks with my 3Lb brass hammer to form them. Here's a picture of a 225Win project I did what I just described.

http://castboolits.gunloads.com/attachment.php?attachmentid=143566&d=1435950318

atl5029
07-24-2015, 08:44 PM
That's an interesting concept, but sorry, it doesn't help me in the slightest. Do you actually have any experience fire forming with cast bullets or reloading with pull down powder?

jrap
07-29-2015, 09:10 AM
Why even use a bullet at all? Use some pistol powder in the case or whatever you have on hand. Fill with wheat germ and then plug the case with a bit of soap. May need to he done more than once but the only thing going down your bore is soap, wheat, and some unburnt powder. Good luck with the rifle!!

cowboybart
07-30-2015, 08:38 PM
I've done it before. I made 257 Rob AI and 7-30 Waters from 30-30. I used a non GC 139gr pill in the Waters and cheap 25 cal pistol bullets in the Roberts. The powder was from 7x57 pull down and was loaded HOT (machine gun ammo??). I pulled it down and loaded the Roberts and Waters brass about 60% full. All fireformed just fine. I did fail with this method making 280 JDJ. I had to use a long bullet seated into the lands to maintain headspace. The 280 cases at 60% were not enough to get a sharp shoulder. I up'ed it to 75% and it worked.
You can bypass using a bullet and use a wax plug from a candle or crayon. I never tried this as I load in the winter and may not shoot it for 5 months. I don't know what the wax does to the powder in that time.

cowboybart
07-30-2015, 08:42 PM
PS: let me know how that 260 AI shoots. I have a Marlin XS7 action, a Savage barrel in 65. CM and just got a 243 AI reamer from PTG (I'll bush it up to 6.5mm, then ream the neck, then the throat). I don't have dies yet, but I can cobble something together that will work. I plan on fireforming with good powder and bullets, but I understand the logic in using up an "unknown" powder.