6mm Ackley cream of wheat fireforming

Plumsask

Plumsask

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Hi everyone, currently putting together a 6mm AI, this round is already overbore and not particularly easy on barrels, I have heard of the cream of wheat method and read a bit about it. Does anyone here have any experience in this process? Any pros cons? The other option I have thought about is setting back an old 243 barrel and chambering it in 6AI and use it to fire form my brass- but it would not be chambered with the same reamer as my new barrel, any thoughts?

Thanks

Ave
 
Plumsask said:
Hi everyone, currently putting together a 6mm AI, this round is already overbore and not particularly easy on barrels, I have heard of the cream of wheat method and read a bit about it. Does anyone here have any experience in this process? Any pros cons? The other option I have thought about is setting back an old 243 barrel and chambering it in 6AI and use it to fire form my brass- but it would not be chambered with the same reamer as my new barrel, any thoughts?

Thanks

Ave
Click to expand...

The C.O.W. method works great. My advice is choose a windy day and shoot down wind as it stinks and the COW gets everywhere. A touch of size wax on the shoulders gives better shoulder formation. Fast powder seems to work well. I use 700X to fireform 338 LAI as it is cheap and works well. I also use sheet bees wax pressed into the case mouths to keep the COW inside the casings. Do NOT load it and leave it as there is still some oil in the COW and it will contaminate the powder charge. A few days is ok but months not so much.
 
Thanks for the input- im thinking the cow is the better route to go, and on the note of your 338 Lap AI, what gains are you seeing over a standard 338 L-

Thanks

Ave
 
Its my understanding that with Ackley improved cartridges you just shoot a standard cartridge and the chambers shoulder still holds the case against the bolt face.

First chamber a new unfired case and see any resistance is felt when closing the bolt. If resistance is felt you can safely fire a standard cartridge, if no resistance is felt then check the head clearance.

You can check the head clearance with a standard 6mm "case" and a fired spent primer.

1. Measure the standard cases from base to case mouth and write it down.
2. Now just using your fingers start the fired spent primer into the primer pocket.
3. Now chamber this empty case and let the bolt face seat the primer into the primer pocket.
4. Now remove the case and measure form the base of the primer to the case mouth and write it down.
5. Now subtract the first case measurement from the second and this is your head clearance or the "air space" between the base of the case and the bolt face.

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After the bolt face seats the primer the amount the primer is sticking above the base of the case is your head clearance. Normally after full length resizing your cases should have .001 to .002 shoulder bump and this will be your head clearance with a chambered cartridge.

Note, I have had brand new unfired cases over .010 shorter than chamber headspace. Many shooters just seat the bullets long and jam the bullets into the rifling to hold the case against the bolt face if the cases are too short.

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Well when the time comes I may have to try thebguys 338 AI when my factory barrel is done. Also I have one of your ates AR10 muzzle breaks, very well made- and does the job well,

Ave
 
Just shoot regular loads... you will need trigger time on the rifle anyway, and you will be surprised how accurate it is with standard casings... the question is whether or not the headspace will allow firing a regular case round... IMO, just try one. How many brass are you planning on fireforming for the rifle? 200-300 is no big deal.
 
Ganderite said:
I have used C of W to fire form. I shot it in the basement, aimed at a concrete wall. Warmer than outside....
Click to expand...

Every time i read your posts, it makes feel better about my actions. Makes me realize im not the only one who does this stuff.

Your posts are some of the best. If you do it, its a good idea in my eyes.
 
Ganderite said:
I have used C of W to fire form. I shot it in the basement, aimed at a concrete wall. Warmer than outside....
Click to expand...

I’ve never done the COW to fire form ackley brass, if it’s this simple maybe I’ll give it a try...
I usually fireform using standard loads with faster powder and jam the bullet just so lightly...never had an issue and always can use more trigger time...
 
mikeelliot said:
I’ve never done the COW to fire form ackley brass, if it’s this simple maybe I’ll give it a try...
I usually fireform using standard loads with faster powder and jam the bullet just so lightly...never had an issue and always can use more trigger time...
Click to expand...

That system certainly works, but with known barrel burners using the COW method saves the throat of the barrel from unwanted erosion.
 
Another use for cream of wheat is leading removal. Works amazingly well. Light load, then fill case nearly to capacity, seat lead bullet, shoot a few and lead is gone.
 
Evanguy said:
Every time i read your posts, it makes feel better about my actions. Makes me realize im not the only one who does this stuff.

Your posts are some of the best. If you do it, its a good idea in my eyes.[/QUOT

Same goes here. Thanks to Ganderite for all his informative posts.
Click to expand...
 
Evanguy said:
Every time i read your posts, it makes feel better about my actions. Makes me realize im not the only one who does this stuff.

Your posts are some of the best. If you do it, its a good idea in my eyes.
Click to expand...

I have done lots of things. Some were terrible mistakes - from which I learned something.

Just because I do/did it does not mean its a good idea. It just means I did it.

For example, I shot the C O W at the concrete wall because the first shot was aimed at the door to my shop. Blew a hole it. Not such a good idea.

Most of the things I post here are things that I think the average handloader could figure out how to do safely. But no guarantees.

I could write a long message about things that don't work - like drying lumpy black-powder in the microwave, but I fear Fred Fumble might not notice the "Things that Don't Work" heading.
 
hahah i should have said, 'if you post about doing it' but i do understand what you are saying.

I think some people are by the book and some people write the book. You sir are a writer.
 
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