My point as an observer is, that with good trigger leverage ratios and adjustable sear engagement, it would seem that an open bolt firearm with a decent trigger is possible.
In a closed bolt the job of controlling the bolt can be divided between two springs, the main recoil spring and the hammer / striker spring. The hammer / striker spring can be just heavy enough to provide reliable ignition, which promotes a good trigger pull.
Wasn't originally going to do an AR grip, but in order to make use of the rest of the 25mm carbon fiber tube I have as a stock tube, it's gonna be a straight line configuration like the AR, so that necessitates a protruding pistol grip.
Would a hammer-head type of grip be better for your design?
It will take extra material to machine a rail on top, and extra material is extra weight.
In a closed bolt the job of controlling the bolt can be divided between two springs, the main recoil spring and the hammer / striker spring. The hammer / striker spring can be just heavy enough to provide reliable ignition, which promotes a good trigger pull.
Have you messed with many center fire bolt guns? Lots of force in the firing pins, try pulling the tailstock back with your fingers.
Yes, as a matter of fact I have. The point is not that firing pin springs are in some way weak, but that open bolts require the trigger to deal with even MORE spring pressure.
There's a bit more to it than that;The point is not that firing pin springs are in some way weak, but that open bolts require the trigger to deal with even MORE spring pressure.