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405grain
01-26-2020, 04:47 PM
I'm thinking about modifying the cocking piece on a '95 Chilean Mauser to a CG-63 configuration. This would shorten the lock time and the cocking piece would be better supported in the bolt sleeve. The CG-63 cocking pieces are rare/pricey, while '93 & '95 parts are still cheap and somewhat plentiful. I've read through Dutchman's post about reducing the lock time on '96 Swede's. Shortening the sear engagement lug on the cocking piece would be pretty straight forward with a carbide end mill and finishing with some hand stoning, but moving the safety engagement slot back would be a little more challenging. I switch out the Mauser trigger for a Timney sportsman, but I don't want to use a trigger mounted safety. Trigger mounted safety's only block the trigger and sear mechanism, while the Mauser flag type safety retracts the entire cocking piece and firing pin, and are much better.
The cocking piece is hardened steel (I don't know if its case hardened or through hardened, but the ones I've seen act like they're through hardened). Making the slot for the safety engagement would best if using a "slitting saw" mill cutter in an arbor, but these are high speed steel and would probably only work if the cocking piece was annealed. It could be done with a really small carbide end mill without annealing the part, but a brittle and tiny end mill like that cutting a hard part could easily go "ping".
What do you think the chances are that the cocking piece could be annealed, then machined, then re-hardened? I've got some old and not so good '98 and '93 cocking pieces in my junk drawer. I'll anneal a pair of them, make some test cuts in the mill, then heat treat one and case harden the other to see how it works. I'm just looking for some advise because, along with doing this test, I value the input of board members here.

pietro
01-26-2020, 07:25 PM
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I've ground through very hard(ened) steel w/o annealing, using a thin emery disc in my Dremel.

(top row below - 3rd & 4th discs)


https://i.pinimg.com/originals/ca/2a/ba/ca2aba5c2e61a41c69bee5b95a1ec84f.jpg


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samari46
01-27-2020, 02:11 AM
Don't know how hard those cocking pieces are but they are hard. I shortened my cocking piece from the back end. then I used a tantung bit to finish it off.Tantung tool bits can be ground until they turn red and not loose their temper. Give it a nice sharp edge and will cut hard steel.But you will have to remove one of the lugs on the firing pin. To keep the cocking piece on the firing pin I drilled and tapped the back end of the fireing pin for a 1/4 x 20 aircraft socket screw.Little blue locktight and it won't come off. Frank