Cream of Wheat Fireforming...?

[daniel brothers]

Cream of Wheat Fireforming...?

Is it really needed...?

These 22-243AI and 20-250AI wildcats are my first calibers that I've had to form Lapua brass, and don't mind doing the cream of wheat thing...but was wondering if it REALLY makes a difference while working up a load for these calibers.

I've been shooting and forming brass with regular loads, but have some new brass to form and thought I'd save time, money, and barrel life if I did the wheat.

Can I get a true reading if I work up loads with unformed brass... or do I absolutely need to fireform them first...?

 

[stomp442]

If they are new barrels I always just find some cheaper bullets in the weight I want to shoot and just fire form as I break in the barrel. After break in I don't fire firm anymore until I clean then I will fire form 3 or 4 as foulers. The cow method works OK but you only end up with about a 95% formed case and fire forming needs to be completed anyways.

 

[MagnumManiac]

No, there is no point working up loads in cases that have not been fire formed to the improved chamber, you will get much lower velocities do so.
I fireform several cases without bullets, I DO NOT use cream of wheat or any other fillers other than a twist of tissue/toilet paper. This is enough to blow out the case and provide perfect headspace for the next shot without stretching the case.
I find a powder that is bulky enough to give at least 75% load density. The best powder I have found for this is Hodgdon's Clays.
The comment about only getting 95% forming is moot, the next load will give you a very nicely formed case, accuracy or velocity will be barely different, too, from formed cases using bullets.
Have never seen a perfectly formed case from the factory with perfectly formed shoulders, it makes no difference.
I suggest you try this, it has worked for me for years.
I use a square of toilet tissue, for the 22-250 size case I cut in half, twist and poke into the case below the case mouth, that's it. I used to put soap or wax on top, it's unnecessary.

Cheers.
gun)

 

[RockyMtnMT]

Yep, 3/4 case full of shotgun powder, top it with a wad of cotton, shoot it in the air. Goes best with your favorite beverage.

I have been using tite wad.

Steve

 

[J E Custom]

Firearms were not designed to shoot anything but bullets. the quickest way to get into trouble is to stuff something else in the barrel/case.

I fire form all cartridges using the correct powder and bullets. different cartridges need to be set up correctly to get the best results and a good fire form the first time.

I build a lot of AIs and Wildcats and with the proper set up actually hunt with them while fire forming.

I can expect sub 3/4 moa while fire forming and have come to expect 1/2 MOA most of the time.

I am in the process of building a new wildcat design that I call the 338 Texan that starts with a 375 RUM case (average case capacity 104 grains of powder) and ends up holding an average of 118 grains of powder after blowing it out and lengthening it .100 and changing the shoulder to 40o,
plus reducing the caliber of the case to 338.

This case has everything possible done to it and while fire forming the cases with 106 grains of Re 33
and a 225 grain bullet the groups averaged .178 .

So I have a good start on my load development while braking it in, and very well formed cases.

Is other means of fire forming necessary ? NOT IN MY OPINION.

J E CUSTOM

 

[royinidaho]

This case has everything possible done to it and while fire forming the cases with 106 grains of Re 33
and a 225 grain bullet the groups averaged .178 .

Is other means of fire forming necessary ? NOT IN MY OPINION.

J E CUSTOM

J E

So, yur sayin I can or should skip the COW thing and but leave the neck bump (head space), use a "fairly" stiff dose of US-869 (can't use stick powders - pwdr bridging) in my 270 Allen Mag and go to shootin?

My "normal" load is 99 gr US-869 and a 165 Matrix offering.

Should/could I "work up a fire forming load that comes close to the fire formed load's velocity, validate zero and go hunting? What are your considerations when you fire form while hunting?

I've burned several boxes of COW. Hate the smell. Heats the barrel. Leaves a ring at the case mouth which chips off and gives me the vapors. Doesn't completely fire form.

 

[Lefty7mmstw]

Personally, I use a start load with a medium powder for the fire formed caliber when I open up 375 h&h to 7stw. I've tried the cow thing (with farina) and I hated it. The barrel was a dang mess afterward and I think cleaning it tore out as much barrel life as the mild ammo would have. Didn't get the time with the rifle actually shooting groups either using cow. Went to shooting fire forming loads and got good trigger time with the rifle and some clover-leafs to go with it.

with the stw it was the semi formed brass with the neck bump ( sub shoulder) at the proper headspace point and enough 4831 for a stw start load with 120's.

If your sub shoulder isn't that big ( and you aren't belted) use a long bullet and jamb it good into the lands with an appropriately mild load.

 

[Bill Johnson]

Since I shoot a lot of cast bullets, I'll fire-form just about any case, AI or not, by using a reject cast bullet seated over a moderate charge of 2400 (because I had kegs on hand) and seat the bullet so it's .050 into the lands. This ensures complete fire-forming and keeps the case head against the bolt face.

Ya, COW stinks!

 

[stomp442]

I have always been able to find great accuracy while fire forming as well. My fire form load for my 6.5-06AI is 57gr of Ramshot magnum and a 140 match king at the lands. Gives me 2900 fps and half inch groups at 100 yards.

 

[J E Custom]

J E

So, yur sayin I can or should skip the COW thing and but leave the neck bump (head space), use a "fairly" stiff dose of US-869 (can't use stick powders - pwdr bridging) in my 270 Allen Mag and go to shootin?

My "normal" load is 99 gr US-869 and a 165 Matrix offering.

Should/could I "work up a fire forming load that comes close to the fire formed load's velocity, validate zero and go hunting? What are your considerations when you fire form while hunting?

I've burned several boxes of COW. Hate the smell. Heats the barrel. Leaves a ring at the case mouth which chips off and gives me the vapors. Doesn't completely fire form.

Hello Roy.
That is what I do every time.

If I neck down I use the (Donut) to head space the round buy short sizing the neck brass .004 to .006 shorter than the chamber. (You can close the bolt on it and it will fire form with zero
headspace) this holds the case firmly against the bolt face to center it in the chamber.

Then I charge it with a starting load of powder and get a well formed case and excellent accuracy
if you want a little more velocity you can bump your favorite (Tested) load up by 2 grains less than your maximum and you can use it like it is.

If you neck up to a larger caliber. then I use a starting load "only" and seat the bullet .005 into the lands to maintain zero head space. both methods work and accuracy is excellent.

Often I build several rifles for someone(1 a match grade rifle and one a hunting weight rifle with the same chamber head space so the owner can Hunt with his hunting rifle and fire form brass for the match rifle and the hunting rifle.

A friend has this set up and has taken deer beyond 600 yards while fire forming his brass.

All rifles will normally perform better once the brass is fire formed but with the ability to hunt
(Even if it is shorter distances) and fire form at the same time, saves barrels and components (Money).

Brass needs to be well fire formed or you will have to fire form it with a stiff load to be ready for accuracy testing. Other methods don't produce sharp angles at the shoulders. :And the cornbread
taste like crap.

It is not the only way to fire form but it is the way I do it.

J E CUSTOM

 

[royinidaho]

Thanks, J E

 

[BountyHunter]

a lot of people have experienced the case flowing forward from the base rather dramatically and case head separation after 4-5 shots using the "jam the bullet" technique versus a more uniform flow.

However, when you either neck up or down and leave a bulge on the case neck where the case will "just" chamber tightly, that issue is not present.

I always opt for the latter technique and have never run into issues once I started doing that.

 

[Lefty7mmstw]

a lot of people have experienced the case flowing forward from the base rather dramatically and case head separation after 4-5 shots using the "jam the bullet" technique versus a more uniform flow.

However, when you either neck up or down and leave a bulge on the case neck where the case will "just" chamber tightly, that issue is not present.

I always opt for the latter technique and have never run into issues once I started doing that.

not enough neck tension then.... crimp your bullets if you aren't putting enough neck tension into the case. you are not really looking for accuracy with fire forming loads, but a lee factory crimp die will help with neck tension if you are getting some slippage and you still want serviceable accuracy.