cream of wheat fireforming with pistol powder

[Mateo]

I've got my cases with the pistol powder, the cream of wheat, and the wad of tissue paper keeping it all in. I'm wondering if there is any threat of throat erosion here? I have 150 cases to fire. SAUM cases. I know there is a bit of heat. but I cant imagine too much? There's some pressure, but has to be a fraction of what a case with a projectile would cause. I can see there being a bunch of carbon to clean out. I think I might have just answered my own question. anyone have thoughts? these are SAUM cases with theirshoulders bumped back .100". the fireforming will give it a 40 degree shoulder and blow out the taper.

[Big Lou]

I’ve done some forming with the COW method. I noticed nothing adverse. It works well enough. A little tinkering with charge until you start getting sharp shoulders and you’re off and running. You’re playing with a bit different animal than myself as I’m just doing 6mm Rem to 6mmAI but I tried both methods and prefer to just find a load that performs well and shoot to form cases. Creating a false shoulder seems to have helped in fire forming as well. I’ve had less splits in the shoulder area but it wasn’t super common in happening anyway. Sectioning of cases appeared better too. I noticed the tiniest bit of thinning back towards the case head without false shoulders and see no indication of the thinning with. My measurements showed that I wasn’t getting a fully formed case until I fired a full power round anyway so it seemed like the way to go. I never did try jamming a bullet on forming either so can’t comment there. Not sure if any of that is helpful or not. Haha

[Pathfinder76]

They will generate quite a bit of heat. I let my barrel cool every once in a while.

[Cheyenne 1]

I just chambered up a fireform barrel.
Likely about as ugly as you can get. Lol
Will be the cream of wheat pistol powder method.
It’s for a 6mm Br to a dasher.
I can’t post picks. But used a savage nut on a stiller action. No need to make a false shoulder. Just adjust the nut for head space
Best part no need to worry about your good barrel.

[Pathfinder76]

If you can swing it, that’s a fantastic option!

[DLab]

Originally Posted by Cheyenne 1

I just chambered up a fireform barrel.
Likely about as ugly as you can get. Lol
Will be the cream of wheat pistol powder method.
It’s for a 6mm Br to a dasher.
I can’t post picks. But used a savage nut on a stiller action. No need to make a false shoulder. Just adjust the nut for head space
Best part no need to worry about your good barrel.

Honest question here.
Forming 6 BR.brass to Dasher you need to blow the shoulders forward to lengthen the case, making a false shoulder on the neck assists in doing this,also helps centre the case in the chamber for uniform forming.
If you don't make the false shoulder to index off and use the method you're describing,how do you know the shoulders are moving forward and not the case body stretching?

[Dubious]

Never had a lot of luck with cow the shoulders where not as crisp as a full load and had to be fired a second time so I just started using false shoulders and shooting a forming load. The forming loads where still fast and just as accurate with no need to clean out any cream of wheat in the rifle in my experience cow was an over rated bandaid approach.

[DanOO]

I have seen some pretty fouled barrel using the COW process, the temperatures of the powder burn really bake the stuff onto the bore.
If you use this method you will need to do serious cleaning of the bore with solvents and brushes to get it free of this contamination.

[DLab]

Originally Posted by DanOO

I have seen some pretty fouled barrel using the COW process, the temperatures of the powder burn really bake the stuff onto the bore.
If you use this method you will need to do serious cleaning of the bore with solvents and brushes to get it free of this contamination.

The OP stated he was using a fire forming barrel chambered for this use.

[Cheyenne 1]

Originally Posted by DLab

Honest question here.
Forming 6 BR.brass to Dasher you need to blow the shoulders forward to lengthen the case, making a false shoulder on the neck assists in doing this,also helps centre the case in the chamber for uniform forming.
If you don't make the false shoulder to index off and use the method you're describing,how do you know the shoulders are moving forward and not the case body stretching?

Maybe a bit hard to describe how I did it.
As it’s not really a chamber cut to shoot bullets. You cut the chamber, till you get the brass in the barrel where you want it.
Then thread on the action, put a piece of brass in and adjust nut (savage nut) till you get it snug when you close the bolt.
It is held on the end of the brass, the lip of that’s what you want to call it so it can’t move.
And 8.5 grains of bulls eye and some cream of wheat. Works good.
This was cut on a piece of barrel, that’s likely a foot long.
I can text or email you a pic of it.

[DLab]

Originally Posted by Cheyenne 1

Maybe a bit hard to describe how I did it.
As it’s not really a chamber cut to shoot bullets. You cut the chamber, till you get the brass in the barrel where you want it.
Then thread on the action, put a piece of brass in and adjust nut (savage nut) till you get it snug when you close the bolt.
It is held on the end of the brass, the lip of that’s what you want to call it so it can’t move.
And 8.5 grains of bulls eye and some cream of wheat. Works good.
This was cut on a piece of barrel, that’s likely a foot long.
I can text or email you a pic of it.

That's a method I haven't heard of,interesting.Do you drop 1-2 grains with a bullet jammed for final forming of the shoulders or full load bullet seated to jump?
If you can ,post how it works out for you.
Thanks

[fps plus]

The last gun I fireformed for I used Traill Boss with the bullet jammed into the lands. It worked fine and fully formed the shoulder. No need for any filler in the case as it is a bulky powder

[Cheyenne 1]

Originally Posted by DLab

That's a method I haven't heard of,interesting.Do you drop 1-2 grains with a bullet jammed for final forming of the shoulders or full load bullet seated to jump?
If you can ,post how it works out for you.
Thanks

My fire form load I use is 9.5 grains of bullseye, filler and some paper towel for a plug. It isn't to bad to do I set up a powder thrower for both the powder and cream of wheat. That's for a BR to dasher.

The neck is pushed forward to make it the correct length. Only thing is the shoulders are not as sharp as they will be the next full load firing.
But over all length and distance to neck shoulder junction are good.

So next loading is just regular loading.

I have also seen guys fire form brass at competitions. Shooting a bullet jammed into the lands and a regular load, watched a guy shoot a 200-18X at 600 yards with this method. Says his guns shoots better fire forming, LOL That was forming 6MM Br to 6MM Brx So it does work.
I have also seen quite a few have fail to fires as they don't have enough neck tension to hold the bullet jammed in to the lands when the shoot.

And it is winter and I am bored and wanted to get a jump start on brass prep. I have 300 ready to form today.

[Ruby76]

Originally Posted by Mateo

I've got my cases with the pistol powder, the cream of wheat, and the wad of tissue paper keeping it all in. I'm wondering if there is any threat of throat erosion here? I have 150 cases to fire. SAUM cases. I know there is a bit of heat. but I cant imagine too much? There's some pressure, but has to be a fraction of what a case with a projectile would cause. I can see there being a bunch of carbon to clean out. I think I might have just answered my own question. anyone have thoughts? these are SAUM cases with theirshoulders bumped back .100". the fireforming will give it a 40 degree shoulder and blow out the taper.

Sherman short? I started doing what you are planning with cow, shoulders didn’t form all the way so I still had to fireform with a bullet. I’d Just do a reduced load with a bullet and skip the cow fireform.

[Mateo]

Originally Posted by Ruby76

Sherman short? I started doing what you are planning with cow, shoulders didn’t form all the way so I still had to fireform with a bullet. I’d Just do a reduced load with a bullet and skip the cow fireform.

Yeah, Sherman Shortmag. what was your reduced load? I have H1000 I want to use for the reduced load.

[qwert]

Originally Posted by Mateo

Yeah, Sherman Shortmag. what was your reduced load? I have H1000 I want to use for the reduced load.

I suspect a reduced load of H1000 might give you very square shoulders, because you may be missing your head.

Google "secondary explosive effect" and "SEE".

Good Luck, YMMV.

[Pathfinder76]

Why are sharp shoulders important again?

[Buckhead]

Apparently some shooters like to have a consistent case volume.

[Pathfinder76]

Originally Posted by Buckhead

Apparently some shooters like to have a consistent case volume.

Case volume is easy to measure. Have we done that?

[Ruby76]

Originally Posted by Mateo

Yeah, Sherman Shortmag. what was your reduced load? I have H1000 I want to use for the reduced load.

Which caliber did you build? For fireforming my 338SS I used a 200 grain accubond and 59 grains of RL22 (cause I had it laying around). I'll check my notes again but I also used N560, again because I had it and wasnt using it for load development. Figured while I was fireforming it would break in my barrel anyway. Other guys have used different powders, just reduced by 10% or so.

[Buckhead]

Originally Posted by chuck

Case volume is easy to measure. Have we done that?

I don't do it. The most I would ever do is sort them by weight from the same lot number. And I would never go to the trouble of this COW method.
Form a false shoulder and fire some full power (or close) loads. Done.
If I waste a few cases and loading supplies - so be it.
That's just me, though. Others have their own opinions and methods of conducting their affairs.

[Arctic]

I've done so many, don't think of it as complicated, just 11 grains of Bullseye, 1/4 sheet of TP, Cream of Wheat or Cornmeal, and a bit of wax. The odd time it requires a 2nd firing, and then trim! Oh, and a pistol primer!

[Mateo]

Originally Posted by qwert

I suspect a reduced load of H1000 might give you very square shoulders, because you may be missing your head.

Google "secondary explosive effect" and "SEE".

Good Luck, YMMV.

googled it. nothing that makes sense to what you are implying. care to elaborate?

[Mateo]

Originally Posted by Arctic

I've done so many, don't think of it as complicated, just 11 grains of Bullseye, 1/4 sheet of TP, Cream of Wheat or Cornmeal, and a bit of wax. The odd time it requires a 2nd firing, and then trim! Oh, and a pistol primer!

try reading the whole post and not just the title. it'll help you contribute more.

[Mateo]

Originally Posted by Buckhead

I don't do it. The most I would ever do is sort them by weight from the same lot number. And I would never go to the trouble of this COW method.
Form a false shoulder and fire some full power (or close) loads. Done.
If I waste a few cases and loading supplies - so be it.
That's just me, though. Others have their own opinions and methods of conducting their affairs.

the only reason i'm not doing a full power load is others have found this reduces brass life. mainly the primer pockets. that first full load seems to cause a pressure spike that isn't there with fully formed brass. and the primers start to fall out after only a few firing after that. I did my first batch with the reduced load and norma brass. And that brass lasted a really long time. then When i did another batch of brass (remington) i only got half the firings before the primers were loose. I chalked it up to different brands of brass and hardness. But now that the popularity of this cartridge has increased ( I was the first in canada with the SS) notes are being compared and the full power load on case forming has shown a reduced primer pocket life.

[Mateo]

Originally Posted by Ruby76

Which caliber did you build? For fireforming my 338SS I used a 200 grain accubond and 59 grains of RL22 (cause I had it laying around). I'll check my notes again but I also used N560, again because I had it and wasnt using it for load development. Figured while I was fireforming it would break in my barrel anyway. Other guys have used different powders, just reduced by 10% or so.

I did the 6.5mm. I've been using the 140 gr VLD and 60 gr N570. tried a few others but this did exceptionally well, especially with norma brass.

[Mateo]

Originally Posted by chuck

Case volume is easy to measure. Have we done that?

how does that help here? And sharp shoulders are sure signs of a fully formed case when it comes to wildcatting and forming brass. round edges are caused when the COW method is used and internal case pressure isnt enough to flow brass into the tight edges of the shoulder, but it enough to blow out the taper, push the shoulder forward to the angle of the wildccat design. Usually 40 degrees to get added case volume and limit brass flow forward that requires case trimming to length.

[qwert]

Originally Posted by Mateo

googled it. nothing that makes sense to what you are implying. care to elaborate?

Just a play on words to caution regarding SEE, and multiple reports of extreme material failure events ('KB'), when reduced loads of slow powder were fired.
There are reports of fatalities, and serious injuries, and total destruction of firearms & optics.

AFAIK, the cause of SEE has not been definitively identified, or reproduced in the lab. Explosive forces can be surprising.

Boxers know to 'protect yourself at all times'.

This is why many choose relatively fast powders known for their stability with reduced loads.
Lots of experience and advice from the castboolits crowd.

Good Luck, YMMV.

[Ruby76]

Originally Posted by Mateo

I did the 6.5mm. I've been using the 140 gr VLD and 60 gr N570. tried a few others but this did exceptionally well, especially with norma brass.

Recognized your username later from LRH. Are you using ADG brass now? I've been playing with some for a while and have some proper 338SS headstamped to fireform.

[1100winger]

I'm not sure COW FF will give you sharp corners on first fire.

My wrinkle to this discussion - I buy a large wax candle from the dollar store, and plug (contain the COW) the case neck with wax. Need to brush the bore every 10 shots or so, but the mixture stays in place.