How do you fire form your cartridges?

dthunter

dthunter

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I have used 30-06 cases to make 25-06, 35 Whelan.
308 win down to 7mm08, & 243win.

I have always created a false shoulder by changing the caliber of the neck with expanders and dies. Once i achieved a crush fit upon closing the bolt, I loaded up a midrange load and fireformed the case through live fireforming. It has always worked for me.


Today one of us gunnuts explained to me how to use a pistol powder and cream of wheat to fireform. I understand this to accomplish the same goal and save on barrel life. Seems like a smart idea when investing allot of money on custom match barrels!

What proceedures do some of you gunnutz use to do this "bullet-less fire forming?
How do/ what do you load, etc?

Interesting stuff!
 
I think I read somewhere you want to use a max charge to fire form cases.....

I'm forming some tomorrow!

Pistol powder and Cream of wheat eh?? very interesting, how would you go abouts creating a load??


Side note.... when you made your 243 out of 308 did you need to case/neck turn?
 
what you do is you take unfired brass and load it, or new factory ammo ... then you shoot it on your gun. Voila' ! fire formed ! lol
 
I think Jerry Teo uses the cream of wheat method, hopefully he will chime in here. I've got some new Lapua brass to fire form and would like to try it.
 
I just buy 5 or 6 boxes of the intended ammo, shoot it in the intended rifle, now i have fired form case to my rifle, often i find that the best accuracy lay in necksizing only, sure give me stellar accuracy in my Nemesis, Icon PH and FNH rifles ( and soon Model 54 Cooper in 308 )... JP.
 
slicknova said:
I think I read somewhere you want to use a max charge to fire form cases.....

I'm forming some tomorrow!

Pistol powder and Cream of wheat eh?? very interesting, how would you go abouts creating a load??


Side note.... when you made your 243 out of 308 did you need to case/neck turn?
Click to expand...


Yes, I did neck turn, but I didnt take too much off.
I cleaned up about 90 percent of the neck surface
 
The reason I am looking to fire form cases from 30-06 to 280 rem. is that I have over 1500 once fired 3006 brass. It just makes sense for me to use it, instead of paying more money for something I already have.
 
I haven't tried the cream of wheat method but it has been around for a long time and is in a lot of reloading books as a good practice, it should work well. I usually try and get brass with the correct headstamp as i shoot a lot of different calibers and it is easier for me. If you have a lot of 30-06 brass and don't have that chambering well either sell the brass, use it for other suitable rifles or get a 30-06.:D
 
Neck down to form a false shoulder. Location so that there is resistance in the final 1/4 of bolt closing. If you extract now, you should see a shiney mark on the false shoulder. It must be compressed to ensure the case head is tight on the bolt face at lock up.

Any LR primer.

Light charge of pistol powder. I use Titegroup.

Cornmeal or cream of wheat to base of neck. The stuff you need to cook not instant. Keep ANY AND ALL MOISTURE away from this stuff and the cases.

Stuff a small piece of paper towel into the neck so the cornmeal doesnt drip out. DO NOT PACK IT DOWN. Just a light touch ontop of the cornmeal.

Fire at the range. Try and keep the wind at your back. If shooting into a headwind, you will understand the previous suggestion.

Clean chamber as needed to keep cases from little dents. Swap the bore periodically.

The goal is to move the shoulder NOT fully form a sharp corner in the shoulder. When done properly, there can be a slight rounding of the case. If you add more powder to try and get a sharp shoulder, pressures will soar and risk damaging you and rifle. From pop to kaboom, doesn't take a huge change as you a compressing what can become a solid.

The first smokeless load with bullet will form the case perfectly and you can develop a very accurate "forming" load

Do all your basic brass prep. Outside neck turning is usually a good idea if sizing down cause the necks will thicken. I consider this a good thing as I want to control my neck thickness.
Jerry
 
I fire form with a subsonic load that uses a cheap heavy bullet jammed into the lands and Trailboss powder. No false shoulder needed. Way faster to do and a hellava lot more fun that firing Kleenex and cereal out the barrel. It gives me the a nicely formed case and low neck runouts, and doesn't seem to have any effect on barrel life.

P1060043.jpg

Left: Unformed 6mm Rem case, Center: 6mm Crusader cases formed with subsonic loads, Right: 6mm Crusader case with several firings on it.
 
Nice wildcat.... Cheap Heavy Bullet - love to find some of these :)

If you have to reposition a shoulder AND have a cal change, you can't do that just by jamming a bullet into the case. How do you make 280 brass from 30-06 brass with just a bullet jam?

The Crusader looks to be an improved 6Rem case. If yes, why not just chamber a few thou short vs the brass you have and FF that way? Now you dont even need that first wasted bullet. You can do directly to a suitable full pressure load and form like any other Ackley chambering. usually, that load can shoot really well... just a bit slower.

Jerry
 
Cast bullets are pretty cheap.

Just neck up/down the case, then do the bullet jam.

It has similar case capacity to a 6mmAI, but it is not the same. The case body taper is made to match the 308 so that it fits AICS mags perfectly. The shoulder angle is less steep so that it feeds reliably when you run the bolt quickly. The AI sometimes hangs if you go too fast. You don't always get tight fit against the 6mm Rem shoulder. The bullet jam guarantees that the base is tight against the bolt.

I've tried all ways of fire forming it, and that is my preferred method. Yes, the bullet adds cost, but it doesn't take as much work as CoW and isn't wearing out the barrel like a full power load. I've never needed to do a second full power firing to get good groups out of it like the CoW method either. First full power groups are better than full power fire forming ones without being slower.
 
Lots of ways to solve. I do like the idea of a shallower angle for a mag fed case. 30deg is about as sharp as I think necessary.

65Mystic_zps89d75a4e.jpg


Before and after for my 6.5 Mystic. Same would be a 260AI if going from 308 brass. False shoulder necessary and the necks are rarely ever straight after sizing down to stick a bullet in. COW is necessary.

Nice to see more wildcatting being done. Shooters will learn a ton when they start changing from the norm.


IMG_0773_zps96553668.jpg



Jerry
 
At the time, there wasn't any quality 260R brass to worry about.

I didn't want deal with the donuts using 243.

Had a solid supply of 308W and it allowed me to outside neck turn to my desired dimensions. Also, a nice large internal case volume and strong brass.

Jerry
 
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