Cocking piece pin tilted in bolt

[RWL1]

Is it normal for the Cocking piece pin to tilt rearwards rather than sticking out of the firing pin/cocking piece at a 90º angle? If not, what's the solution? This is a 12 FV but the same bolt mechanism is probably used in other 110 series rifles.

[strut64]

All 10/110 actions use the same cocking mechanism. 90 Deg is the coreect position. You might have some excess wear or off sized hole in the firing pin. The fit is supposed to be snug of the pin in the hole.

[RWL1]

My cocking piece pin is fairly loose in the cocking piece. Should the pin be long enough to engage the hole in the opposite side of the cocking piece or does it normally end in the large central hole of the cocking piece?

[mnbogboy2]

Picture?

[chetc]

send bolt assembly to SSS, they will cure that problem forever.
chet

[RWL1]

Picture?

Can you do that if you're not a paid member? If there's a URL where I can upload the photo I will. Since Photobucket blocked third parties from showing photos there are a lot of blank spaces in forums where pictures used to be.

[RWL1]

send bolt assembly to SSS, they will cure that problem forever.
chet

It looks like the sort of thing that I could do myself. Not sure if I need to although looking at it slightly angled irritates me. The pin does not touch the cocking notch when in the fired position, but this is a used gun so I can't say that at some point a previous owner had it adjusted so that the cocking piece pin was being battered on firing. I can't complain about the gun not shooting well though; I shot seven sub minute of angle groups in a row last week and I'm still working up loads for it. American Eagle factory loads though - pffffft. Those gave 1.5 to 2" groups.

[mnbogboy2]

RWL1, sent you a pm.

[mnbogboy2]

5247
5248
Here are pics from RWL1.
First thing I would do is disassemble the bolt
My guess is both pin & firing pin.

[mnbogboy2]

Cocking pin looks bent. Maybe firing pin hole is still tight.

[Fotheringill]

It definitely looks bent and/or the sleeve that it sits in is itself bent or torn apart.

Bolt needs to be taken apart. No need to take apart extractor/ejector for this. It will come apart easily enough but there is a trick on reassembly. There are a few You-Tube videos on the disassembly/assembly. Pay particular attention to the assembly. If the pin is straight and a gorilla bent the sleeve, get it replaced.

Signed-

A Lowlands Gorilla

[RWL1]

I had already taken the bolt apart to do a lift improvement - 38 Spl case w/ ball bearing and a spacer for the bolt action screw. The hole in the cocking piece is slightly large for the pin. I'm going to be tied up for a few days, but one thing I could do would be to measure the diameter of the pin and the hole in the cocking piece to see how they compare in size to "normal".

[sharpshooter]

According to the print.....cocking piece hole diameter should be .217", the cocking piece pin should be .213-.216". I'm betting both are out of spec.

[RWL1]

According to the print.....cocking piece hole diameter should be .217", the cocking piece pin should be .213-.216". I'm betting both are out of spec.

Thanks for the dimensions. I'll check them in a couple of days when I can get back to the rifle project. I didn't run a file over either piece. Do you know if either is hardened? Where did you get the print of the parts?

[Robinhood]

That tilt is a bummer. I made some tighter tolerance cocking pieces to fix this issue on a couple of actions. Time to replace some parts.

[RWL1]

That tilt is a bummer. I made some tighter tolerance cocking pieces to fix this issue on a couple of actions. Time to replace some parts.

I'm considering doing that. I'll have to wait until next week to take the bolt apart and check the measurements, but the cocking piece looks like it would be a simple lathe project unless the threads on the firing pin are some odd proprietary size.

[mnbogboy2]

1/4-28 standard thread If I remember correctly (added threads once).

[sharpshooter]

The pin itself is made from 8620 leaded and is case hardened to R15N 90 min, .006-.010" case depth. If you don't recognize those numbers it's because it's a scale just for case hardening. It's the equivalent of 56 Rc. I'd just use O-1 drill rod.


the source of prints.......let's just say I'm well connected.

[Robinhood]

I just made the cocking piece to fit the pins closer Fred. I bought a chucking reamer to keep the hole diameter close. Its in my box and I don't remember for certain but I'm thinking a 5.5mm one worked.

[sharpshooter]

A lot of those pins have an excessive amount of chamfer, coupled with the excessive amount on the cocking piece which leads to less surface area to keep the pin from tilting. As long as the shank is filling the hole from side to side for better support, the straighter it will stay.

A long time ago, Savage entertained the thought of making the cocking piece pins with a square head. Prototypes were made that used a flat keyed hole in the cocking piece to mate up to a flat on the pin to keep them from rotating when the bolt was retracted. The idea of the square head was to reduce the load on the sear, thus reducing trigger pull. It never panned out, so the idea was scrapped.