Does anyone know anything about this broadhead? My dad gave me a couple of arrows he used at one time with this broadhead on them. It is a 3-blade head with a helical twist on the blades.

The following is stamped on the broadhead.

Spiral Killer, Pat No 236879, E. Miller, Orem, UT USA

email to you

I believe your describing a Serpentine head made by Browning.

If this head is a Serpentine then why would it be stamped Spiral Killer?
wood slinger: I sent you an email, please respond.

Browning Serpintines were actually only a two blade.  Each blade turned into a narrow ribbon which twisted to the rear of the ferrule.  The Spiral Killer is indeed a three blade, much like an MA-3 except the blades have a helical twist.  Spiral Killer broadheads were a division of Miller Ski Co., Oram, Utah.  You know they were made a  long time ago, they sold for under $6.00 a dozen.   Bow'narrow