Regarding the building of a .577 Nitro double using the 650 grain bullet hopefully at 2000 fps or thereabouts, here are a couple of questions.

1 What would be your estimate on the minimum safe chamber wall thickness required when using a monobloc system?

2 Would there be any real benefit in using the 3 inch case rather than the 2 3/4 inch case?
Pressure would be lower but achieving maximum loading density/reliable ignition may be more of a problem?

3 What should the minimum rifle weight be? (double rifle of course)

Thanks