First, these are not technically "bolts" these are socket head cap screws.
Not quite being a Torx Socket, but close enough.
Second, fastener companies specialize in manufacture of bolts and screws etc. Gun companies specialize in manufacture of guns not fastners. I would bet the knowledge machinery metallurgy and heat treat etc etc favors the faster company producing the best product over the gun company for in house manufacture of a socket head cap screw.
Um. Actually Fastener companies specialize in MASS PRODUCTION of the more common types of fasteners. Not necessarily the best quality but the good enough to satisfy a specific requirement (aka Gr. 8 to the cheapest manufacturer, irregarless of thread forming techniques).
An engineering company/design firm (such as those engineering a firearm design) would have a far better understanding of what tolerances and precision is required for their designs. Many designs have specific applications (such as a limited torque bolt), specific heat treatment and hardness requirements which cannot be easily or cheaply done by the Fastener Companies. Fanstenal, Spaenaur, Brofasco, etc..., all manufacter and sell hardware available in the multi-million pieces per year usage. If a Company needs a specific bolt due to some single characteristic, it may be more cost effective to have a custom bolt made, than a redesign to accept a "standard" bolt.
Third, the gun company needs two fasteners per gun. LMT manufactures what? a thousand or so guns per year. That is a 2000 SHCS order so I doubt it is big enough to warrant interest to do a special order or special SHCS run from any fastener company.
Definitely.
Fourth, engineers look in a book to find a fastener that does the job for them and specifies such a fastener. They don't reinvent the wheel.
Ask yourself this, if this fastener is so special, why are there so many available replacement fasteners that are identical, if not superior to the one that is in your LMT now?
Actually they do depending on the application. I do however bet that the original bolts were indeed "plain-jane" from a fastener company.
After the first or second prototype that was stripped during the numerous build up and tear down of the design history, I bet they decided on a torque value and subsequently a torque-limited torx cap screw.
Also it becomes a service/warranty issue. If the user doesn't follow torquing instructions or their torque wrench is out, the screw breaks before really expensive damage occurs. If the user then replaces the bolt with a cheap version. He cannot claim warranty as it is not OEM parts he used.
It may increase the end price by $20-30, but saves the company several man hours of labour (Ever use heli-coils?) and god knows how much paperwork/shipping for repairing/replacing MRP's due to "overtorquing".
