The adapters that we (Vintage Archery or TuffHead) sell are the same adapters that are sold by major supply houses that advertise here on tradgang. I believe at present there is one manufacture in the USA producing most of the adapters.
When designing your arrow set up it is important to identify the weak point in your arrow.the places to look are your
broad head ,adapter, or insert and the arrow it self. Of course if you are shooting wood you eliminate a few weak points except the arrow it self
Using a one piece adapter and insert eliminates one week point that can be identified with a adapter screwed into a insert.This type of adapter can be seen at
www.tuffhead.com Adapters and the post of screw on broad heads can and do bend when heavy bone is encountered particularly with heavy arrows. For hunters going after big game such as buffalo ,moose ect choose there arrow setup carefully.
I know now that the adapters commonly used by most hunters are not to be recommended for heavy bone animals. this has been proven by
Allen and others.
Vintage Archery is in the process of building a Titanium adapter that is 11/32 in diameter and has a taper length equivialent to a 125 steel adapter and will weigh 75 grains . They are in production now. They are made out of grade 5 Titanium and have twice the tensile strength of steel. We will reccomend this adapter for all heavy boned game
For most game hunted in the USA the steel adapter will surface.
Dr.Ed Ashby has had a lot of experience using steel adapters and said he has had the same experience of bending adapters in the 75 grain an 100 grain adapter .He reports no bending in the 125 grain that he tested with. Neither he or I reccomend aluminum adapters of any size.
When hunting heavy bone animals one may choose a heavier bow ,maybe beef up their arrow weight ,add FOC all things that are prudent to do depending on the game being hunted .The same principal applies to choosing the adapter,insert or broad head you use .