Question on fire forming .338-06AI

[levers4life]

Picked up a custom 03-A3 in 338-06AI. I have never fire formed a cartridge before and just wanted a quick run down from someone who does. I have run the 30-06 cases through a Redding FL 338-06 die that expands the neck and sizes the case but doesn't put the shoulder on them. My load with already fire formed brass is 60gr of H335 under a Barnes 160gr TTSX. The previous owner of the rifle told me he fire formed with full loads. Is this advisable or should I use a reduced load and cheap bullet? Any advice is appreciated.

 

[California hog hunter]

I personally use cheap bullets and a mid range charge for the pre AI cartridge. When I do my 280ai with 270 brass. I use 162gr eldm instead of the expensive no lead. I'll just throw out numbers. If the max charge for that bullet was 50gr on a 280 rem, I would load 48gr. I also seat the bullet touching the lands to make sure the case stays touching the bolt face. You can't head space off of a shoulder. That doesn't exist. There are a lot of other ways, too. When I have a new barrel, I fireform my brass and kill 2 birds with one stone. Fire form and barrel break in.

 

[just_jon]

Cream of Wheat method for me. No bullets, no barrel wear. Use a pistol or shotgun powder (I use Green Dot) equal to 1/3 a normal charge weight, fill case with COW and plug with ivory soap. I have fire formed thousands of rounds with this method, and it works every time. If I'm breaking in a barrel at the same time, I use the method described above.

 

[waspocrew]

Numerous ways to accomplish this. You could neck up and then jam the bullets into the lands to ensure proper shoulder formation. Additionally, you could neck up to 35 cal and then back to 338 leaving a false shoulder to head space off. Even with cream of wheat, you'll need to establish a false shoulder for correct headspace.

 

[levers4life]

I've been tied up with work. Thank you everyone for the replies & information. I am going to try the COW method.

 

[std7mag]

IF it's truly based on the Ackley Improved theory, then you can do the following.
1) find 338-06 A Square cases, load to standard 338-06 A Square load and shoot it. The case should have a slight interference where the neck/shoulder junction is.
No need to jam the bullet if this is the case.

2) Forming from another cartridge (say 30-06) you can neck up to 35 caliber, then run it through the 338AI die to get a false shoulder.

3) Neck up to your 338 and seat the bullet jammed in the lands. Load up a mid level charge for the standard 338-06 A Square and shoot.

I've done the above 3, never the COW method.
From my understanding, the COW method is still not 100% formed.

 

[levers4life]

IF it's truly based on the Ackley Improved theory, then you can do the following.
1) find 338-06 A Square cases, load to standard 338-06 A Square load and shoot it. The case should have a slight interference where the neck/shoulder junction is.
No need to jam the bullet if this is the case.

2) Forming from another cartridge (say 30-06) you can neck up to 35 caliber, then run it through the 338AI die to get a false shoulder.

3) Neck up to your 338 and seat the bullet jammed in the lands. Load up a mid level charge for the standard 338-06 A Square and shoot.

I've done the above 3, never the COW method.
From my understanding, the COW method is still not 100% formed.

I've looked all over for some A-Square cases but they're hen's teeth these days. I prefer head stamped brass when I can get it. Here's a pic of expanded case on left (run through the 338-06 die) and properly fire formed case on right. So do I not need to jam the bullet into the lands?

 

[levers4life]

I'm running winchester nickel plated brass to differentiate from my regular cases, 30-06, etc.

 

[std7mag]

I've looked all over for some A-Square cases but they're hen's teeth these days. I prefer head stamped brass when I can get it. Here's a pic of expanded case on left (run through the 338-06 die) and properly fire formed case on right. So do I not need to jam the bullet into the lands?
View attachment 589532

With empty chamber, run your bolt a few times and feel the resistance of the lugs locking.
Now put a standard parent case in and close the bolt.
There should be an increase in resistance.

Ackley designed his Improved cartridges so that they are 0.04" shorter at the neck/shoulder junction.
That firmly holds the case against the bolt so that
1) you can fire form from factory standard cartridges.
2) if you were someplace and you didn't have access to your reloads, you can still use the standard parent cartridge.

This is why if you have a barrel for a standard cartridge (250 Savage for example) you need to get the barrel set back to ream the chamber to AI.

The go gauge for a standard cartridge is the no go gauge for an Ackley Improved.

Savage rifles with the barrel nut have enough space that if you are careful with the reamer, you can screw the barrel in about 1 more turn to set the headspace.
Hence how I have a Stevens 200 in 7mm-08AI with a factory Savage sporter barrel.

 

[waspocrew]

Numerous ways to accomplish this. You could neck up and then jam the bullets into the lands to ensure proper shoulder formation. Additionally, you could neck up to 35 cal and then back to 338 leaving a false shoulder to head space off. Even with cream of wheat, you'll need to establish a false shoulder for correct headspace.

Couldn't edit my original post -

When I wrote this, I apparently had brain fog and was thinking of 338 Gibbs which requires much more shoulder movement, thus why I mentioned forming a false shoulder.

As other have correctly pointed out, with a true AI chamber, a standard case *should* have a slight crush fit when chambering. Then fire away. No need to jam into the lands unless you're not feeling that interference when chambering.

 

[MagnumManiac]

I have had my AI and other improved cases for more than 30 years.
Have tried and used every method…
The one method that works for me every time is COW, Universal powder and a twist of TP. I even use this to form all Weatherby cases from 375H&H brass, as well as others.
Just be sure your final forming load isn't too hot, I always drop back about 5% of max and use that to either hunt with or test seating depth with new bullets.

Cheers.

 

[levers4life]

Thank you all for the sage advice. I'll try to get some time this week to do some reloading and shooting if it isn't too hot. I'll post some results. Hope everyone has a great Sunday.

 

[TRexF16]

COW is what I use in my 35 Whelen AI. No Complaints. Components cost too much these days to waste bullets just on fire forming.