Type S Bushing Die on a 550B

[ZiaHunter]

I am experiencing excessive runout reloading 308 on my Dillon 550B using Dillon dies. I have isolated the problem to the expander ball being drawn through the neck. The greater the neck thickness the more pronounced the problem is. I am wondering if replacing the Dillon sizing die with a Redding Type S bushing die will help alleviate the problem. Has anyone tried this? BTW lubricating the inside of the necks is problematic since it interferes with the powder flowing into the case.

 

[scotharr]

well, the first thing you can do to test your theory is remove the expander ball and see if that reduces runout. Redding makes good dies, but I don't know if that will improve your problem. For example, what if the press is holding the die crooked....new die won't fix that. I use a 550B with Uniquetek/Whidden floating die toolheads and non-bushing F/L dies and have found this combo minimizes runout. bushing dies are very convenient, but non-bushing dies minimize runout...you choose.

 

[ZiaHunter]

I have sized the brass without the expander resulting in little or no measured runout leading me to believe that is the expander. Brass with thinner necks exhibit less runout. I have the Whidden floating tool head installed as well.

 

[MTETM]

I am not sure I will provide you any help, but I load ALL my ammo on a 550 with Type S dies and no expander ball. I have never measured run out, nor do I have any plans to measure it...
I would ask you...does the ammo shoot well? Is it shooting to the rifle's and shooter's capability? If so, who cares if you have run out...?

Good Luck

 

[No1]

I use Type S bushing dies on my 550B, no problems. I do not use any expander ball, that is where my problem existed. I had to switch to the bushing dies and competition seater for my AR10 because everything has to be inline because the bullet jumps so far.
The other option is to use the Dillon die without the expander ball, but you may not want that much neck tension.
Are we to assume you are loading for precision here?
I always lock down a sizing die with a case inserted and ram at full stroke.