Bolt action frustration.

[Drifter]

You might get a better response by starting smaller, like ~50 units or so. Whether a manufacturer or a smaller custom builder, 500 rifles might mean too may eggs in one basket for a prolonged period of time, which could alienate their core customer base.

There are numerous custom builders out there that might could steer you in the right direction. If places like Short Action Customs, Phoenix Custom Rifles, etc are not directly interested, they might know someone starting out, with the skills but lacking the notoriety, that would jump at the opportunity to get their name out there. Of course, you and the builder would need a source for components (actions, barrels, stocks, etc).

Here's an example of how EuroOptics worked a deal with Sako and GAP for a small run (49 units) of semi-custom 22's that took ~1 year to complete:

http://forum.snipershide.com/snipers-hid...-spec.html

If you found the right people, it might be possible to do something similar (but perhaps with fewer options) for Grendel rifles.

I agree that there's opportunity in the market, but I would be apprehensive with a 500-rifle commitment in the initial run.