Personally, I have always felt the hammer block as used on the American Bakers (other than the batavia line) was about the best of all systems. With mechanical connections & the safety engaged there is simply not much chance of it moving. I have also felt an intercepting sear should work somehow in a different direction than the primary sear, less a blow sufficient to "Jar Off" the sear also jar the interceptor out of engagement position. The Lefever design with it's sear engagement on the outer periphery of the hammer is less subject to jar off than those engaging close to the axle. Another very good sear design in my opinion is one found on a J P Sauer/VL&D sidelock ca 1900 I own. This sear also engages on the outer periphery, but the sear itself is mounted vertical & it's pivot is near center. Thus it does not have a "Heavy End" to be so easily moved by a blow.
