On Thursday, September 12, 2013 3:37:13 PM UTC-4, William Bagwell wrote:
Yes, socket*less* cap screws. As in no hole to insert a hex key, but other wise

the same shape and height as the head on a socket head cap screw. Roughly 5/16"

to 3/8" X short, standard or metric, course or fine thread, grade, material

unimportant. Does have to be metal... Thought about ordering shoulder bolts and


cutting the head off. May end up going this route but looking for a less

expensive and labor intensive solution since I may need as many as 50.



Could possibly live with an acorn head if it lacked wrench flats, but prefer

the cylindrical over bullet shape.

--

William

How about these:
http://tamperproof.com/categories/br...removable.html

Breakaway Nut/Non-Removable Security Nut Aluminum
Hex nut breaks away when nut is tightened leaving only the tamper-resistant conical portion. No special tool is required - uses standard wrench for installation.

or these:
http://www.fastenersuperstore.com/bo...FWho7AodyhgA1g

Carriage Bolts have round heads with square necks under the head to prevent the bolt from spinning as the nut is applied. Also offered with ribbed neck.