Whatever happened to Mr. Calfee?--Sear design question

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Was reading one of his ramblings about the fault with the override sear type triggers this morning in "the oval office", and it occurred to me that there are aftermarket triggers that are like the Mauser style, with vertical sears. I do notice the bolt drop movement when the override trigger lets go. I am playing with a Rem 580, like the 788 trigger, now that has the same vertical sear, and with the factory barrel, with some epoxy inletting, I'm shooting Wolf .22 MT into a 30 cal bughole in my backyard(only 25 yds, so far--cold out here). Well I did tune the trigger to 1 lb, by relocating the trigger pivot, and weaker spring, with overtravel screw added, but I'm wondering if anybody found a benefit by changing the sear style in their BR rifles to a vertical release type?? Have at it, y'all...
 
Look at the Remington trigger Kenyon built. It's in Otteman's (sp?) treatise on BR triggers and actions. His trigger sear is pivoted behind the striker catch. Ditto some of the Euro designs. U.S. designs seem to favor pivoting the trigger sear in front of the engagement surface. Get a pair of compasses or dividers, place one leg in the pivot hole, the other at the engagement-- notice rear pivot allows the sear to move away forward as it drops out while the Remington, Jewell, Shilen and Winchester sears must move into the striker before getting out of the way. Main reason for the angled surfaces that are stated to be critical and are responsible for some of the bolt's bucking up as the firing pin is released. FWIW one man's observation
 
Not to be argumentative, but the angle of Remington style sears and cocking pieces in combination with the weight of the striker spring, result in bolts being pushed against the top inside surface of the rear of the bolt raceway pretty much from the instant of cocking. It does not have to buck up during firing, since it is already up.

For the fellow that started this thread: A number of years ago, I was having a conversation with a fellow who was in the gun and action building business, that turned to the effects of bolt clearance, and how that affects lug contact and accuracy. He told me that there was a fellow that had pestered him to work on a Remington rifle, that had a loose fitting bolt, and had given only average accuracy. He took an innovative approach to solving the bolt fit problem for the fellow. He drilled and tapped two holes in the rear bridge of the reciever so that the holes were on either side just above tops of the lug cuts of the bolts raceway, and pointed at the center of the bolt. Then, he fitted ball end set screws so that the clearance was just enough for the bolt to operate smoothly. I believe that he used Loctite to secure them after adjustment The ends of the screws that contacted the bolt had been polished smooth, and were rounded. He told me that after that, with no other change, the rifle shot like a 40X. It may be that when bolt clearance is reduced to a minimum, that the influence that it has on accuracy becomes so slight as to be "lost in the noise".
 
Good idea on the setscrews. I fixed a bolt clearance problem in my Rem F Class, by doing a solder pad with Brownells 44 solder(sort of the same tin alloy as Babbit bearing metal) so that it cammed the bolt down when locked. Then I lapped in the lugs, so they both were engaged when closed. After three seasons, the solder is wearing a bit, can feel a little bolt drop when dry firing, but it tightened groups up. Barrel getting a bit frosty inside now, according to my Hawkeye scope. BTW, you can upgrade the light on the hawkeye for about $16 by installing the mini mag LED kit from home depot, much brighter!
 
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Timney has a rear pivot sear. I've suggested a 90 degree sear lock up with an accompanying replacement firing pin cocking piece. It got very quiet on the phone. Not sure the man understood what I was saying.

Dave
 
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