I might opine that any balloon head auto-rim brass you find might be better directed to an antique cartridge collector rather than reloaded...?

The Starline product is every bit as robust as a 45 acp and I believe they actually state is constructed with the "same integrity as our 45 Colt case"...

This would, I believe, preclude worries about any balloon head pressure concerns?

I use regular 45 acp load data all the time: Buffalo Bore loads three for this caliber and, in addition, three in 45 Auto Rim +P!

Cheers!

P.S. They also state this will not harm any "post War" 45 acp revolvers as well.

P.P.S. They ALSO state their 45 Colt brass is "tested to 44 Magnum pressures" which leads me to believe their 45 Auto Rim brass is pretty durn stout as well (because if a is > or = to b, and b is > or = to c, then a is at LEAST = to c)...