Necking up brass by shooting with inert filler

[Mystic Precision]

Nickle plated brass tends to be very brittle. A big reason they are rarely used when reloading is desired.

I hope you get some success with the COW method. Let us know what happens.

Jerry

 

[bigbull]

Also, make sure that the case headspaces firmly in the chamber. This method works only if the case fits the chamber tightly. If loose, you will need to form a secondary shoulder so that the case doesn't move with firing pin impact.

Jerry

X2

The secondary shoulder is the only way for a proper chamber filling form otherwise its a waste of time since you will have to fireform anyway using a bullet to stop any forward movement of the case, IMO.
bigbull

 

[sakana-lures]

Cow vs Cotton Balls

I just fire formed a bunch of 338-06 AI cases using Bullseye and cotton balls. The cotton balls were used instead of COW. The results turned out very well. I did have to neck the 30-06 cases up to 35 Whelen then back down to 338 to form a shoulder to hold the cases back for firing. 2 cotton balls were put directly on top of the powder. I was worried about burning pieces of cotton setting fire to the range but it was not the case. The barrel stayed clean of cotton fibres.

The false shoulder was needed as my 338-06 AI chamber was cut to long. 338-06 A-Square rounds will chamber but will not fire due to light firing pin hits.

 

[Longwalker]

bc steve, I had good success with Remington nickle 30-06 necked up to .35 W if I first annealed the necks by standing them in a 1" deep water bath and heating the neck / shoulder with a propane torch. discoloured the necks a bit, but splits went to zero.