16ga.com ~ View topic - cheddite hull interchangeable w/ Fiocchi ?

Joined: 23 Jun 2005 Posts: 185 Location: Boulder,Colorado

Looking at some reloading data for Universal Clays. I have heard somewhere that the data for a Cheddite Hull can be used also with Fiocchi hulls. True or no True ?

Thanks, from the 11th hour reloading bench!

Member Joined: 27 Jun 2005 Posts: 1545 Location: Michigan

They may be close with some loads, but I wouldn't go assuming the data can be interchanged.

Use the correct data for each hull.

Both recent Fiocchi and Cheddite 16 ga hulls share similar characteristics. They are both polyformed hulls with plastic base wads. Volume and wall thickness are about identical.

The key to interchangibility between two veery similar hulls is the material, shape, and thickness of the base wad and the relationship of the primer cup to the base of the powder column. Essentially, the base wad shape and the amount of primer cup nose protrusion determine the shape and volume of the combustion chamber.

The easiest way to check two hulls side by side for internal characteristics is to vertically bisect a couple of each down to the metal wad base rim and remove one side of the plastic hull wall. You can then conveniently see the base wads of each hull and can also take some measurements as well.

If the plastic base wads are basically the same shape and the primer cup noses are exposed to the powder in the same way and to the same height, then the hulls will be safe to interchange for any mild to moderate pressure load of moderate shot load weight in my experience.

A word of warning is needed here. Today, quite a few ammo manufacturers who used to manufacture componants and produce ammo in house now contract production or buy componants for most of their promo and hunting ammo lines. They change sources and production locations quite frequently to lower costs and maximize profits. This is being done without any regard to the reloadability of the hulls. Base wad shapes, hull volume, etc can be changed without any warning or exterior information on the packaging. Loading data is also no longer a primary concern. So it has become very important to not assume anything regarding hull characteristics. Check them all regardless of how familiar you think you are with any brand and type of hull.

Joined: 23 Jun 2005 Posts: 185 Location: Boulder,Colorado

Thanks for the "heads up" guys. I am deciding that I'll stay away fromthe Universal powder and stick with the tried and true Unique and my fiocchi hulls.

Thanks for your thoughts