scythefwd
03-29-2013, 06:41 PM
OK, looking at how the bolt interactions with the sear... lets see if I have this right.
the inner tab on the sear sticks up through the groove in the action and interferes with the cocking nob on the bolt from going forward.
You lift the bolt handle, and because that cocking nob is captive, its forced back by the angled part of the cut in the bolt body. Its held in that place by a slight indent. This also compresses the firing pin spring.
You pull the bolt, cycle your round, or just lower the handle.. and the nob pushes up against the sear lever through the action, forcing the sear against the ledge on the trigger. The nob is held back by the sear against the trigger now, and is off the notch in the bolt body.
You pull the trigger, sear slips off the ledge on the trigger, and the spring in the bolt body thats been pushing on the firing pin the whole time (and applying pressure on the sear) overpowers the sear spring and jams the firing pin through the bolt face and into the primer sitting there...
pulling the bolt handle up disengages the locking lugs on the bolt head from the front of the action, so I'd not expect any extra friction on that interaction (though some may occur from the primary extraction at the back of the bolt handle).
SO, here is the point of my rambling.
Polishing up the ramp on the back of the bolt handle should remove any friction occuring during the primary extraction, which should be minimal.
Polishing up the cocking nob handle and the cut on the bolt body that cams it back up into the cocked position should also remove some friction. Making it feel a little smoother, BUT not effect the bolt lift too much, unless those slots are really out of wack.
It appears that you could actually remove a bit of the bolt lift force by going with a weaker firing pin spring in conjunction with a sear spring.
Those two springs are in direct opposition, and while leverage on the sear is going to make this not a 1:1 ratio, I'd expect that dropping them both by similar incriments, you could really take a bit of weight off that bolt lift by almost the number of lbs that you remove from the firing pin spring (again, not 1:1). I think you could really do some good doing this if you could find a replacement sear spring... You can trim the firing pin spring to remove some of the preloading (keeping some as well), but I dont know what to do about lowering the sear spring...
Thoughs, comments, suggestions, "I've already done this and it doesn't work like you think because ... "
the inner tab on the sear sticks up through the groove in the action and interferes with the cocking nob on the bolt from going forward.
You lift the bolt handle, and because that cocking nob is captive, its forced back by the angled part of the cut in the bolt body. Its held in that place by a slight indent. This also compresses the firing pin spring.
You pull the bolt, cycle your round, or just lower the handle.. and the nob pushes up against the sear lever through the action, forcing the sear against the ledge on the trigger. The nob is held back by the sear against the trigger now, and is off the notch in the bolt body.
You pull the trigger, sear slips off the ledge on the trigger, and the spring in the bolt body thats been pushing on the firing pin the whole time (and applying pressure on the sear) overpowers the sear spring and jams the firing pin through the bolt face and into the primer sitting there...
pulling the bolt handle up disengages the locking lugs on the bolt head from the front of the action, so I'd not expect any extra friction on that interaction (though some may occur from the primary extraction at the back of the bolt handle).
SO, here is the point of my rambling.
Polishing up the ramp on the back of the bolt handle should remove any friction occuring during the primary extraction, which should be minimal.
Polishing up the cocking nob handle and the cut on the bolt body that cams it back up into the cocked position should also remove some friction. Making it feel a little smoother, BUT not effect the bolt lift too much, unless those slots are really out of wack.
It appears that you could actually remove a bit of the bolt lift force by going with a weaker firing pin spring in conjunction with a sear spring.
Those two springs are in direct opposition, and while leverage on the sear is going to make this not a 1:1 ratio, I'd expect that dropping them both by similar incriments, you could really take a bit of weight off that bolt lift by almost the number of lbs that you remove from the firing pin spring (again, not 1:1). I think you could really do some good doing this if you could find a replacement sear spring... You can trim the firing pin spring to remove some of the preloading (keeping some as well), but I dont know what to do about lowering the sear spring...
Thoughs, comments, suggestions, "I've already done this and it doesn't work like you think because ... "