excessive cock on close, **updated/resolved**

[WSnyder]

.0380 if I did it correctly.

Is .0380” the difference between the two measurements or is .0380” the not cocked measurement?

 

[Kevin1990]

Is .0380” the difference between the two measurements or is .0380” the not cocked measurement?

think im in a little over my head here. not sure what your asking. my apologies. measure the cocking piece?

 

[WSnyder]

think im in a little over my head here. not sure what your asking. my apologies. measure the cocking piece?

When you push the bolt forward but not rotated and measure the cocking piece protrusion is that .0380”?

 

[Kevin1990]

yes thats correct

 

[Kevin1990]

Cock on close is defined as when the cocking piece engages the trigger block and starts holding the firing pin assy rearward as the bolt goes forward.

Keblys takes great pains to insure that all of their actions have sufficient firing pin travel, which I believe is around .250 inch.

It does not sound like you have a cock on close problem, but a locking lug ramp engagement problem.

if that where the problem, would it still occur without a trigger installed?

 

[WSnyder]

yes thats correct

Then you have .003” clock on close which is nothing. I wonder if the nose of the cocking piece is hanging a bit on the retention groove/hump at the back of the bolt. You say it’s happening at about 10° of bolt rotation. The cams in the action would start to pick up (hand off) much later at more like 40° of rotation and with .003” of cock on close you’d hardly feel that.

 

[WSnyder]

if that where the problem, would it still occur without a trigger installed?

If it’s happening without a trigger then it’s likely the cocking piece nose/bolt issue I mentioned. Without a trigger the bolt lugs generally ride right up the cams smoothly. It is possible something is out of whack there but I haven’t seen it.

 

[Tim Singleton]

if that where the problem, would it still occur without a trigger installed?

This
Take the trigger off and check bolt operation again

 

[Kevin1990]

This
Take the trigger off and check bolt operation again

smooth, no hang up what so ever. cocks and then with a little motion the bolt closes on its own.

 

[AlNyhus]

smooth, no hang up what so ever. cocks and then with a little motion the bolt closes on its own.

How can it cock with no trigger installed?

 

[Kevin1990]

How can it cock with no trigger installed?

my apologies. I meant the cocking piece protrudes upon bolt lift, and it closes smoothly.

 

[Kevin1990]

I might post a video later to show what im trying to describe. either way, ill probably be sending it into kelbly.

 

[Kevin1990]

Here is a link to a video of what I’m trying to describe to everyone. It won’t do this if the trigger is not installed.

Thanks for the help everyone

 

[WSnyder]

It’s hanging at the point of handoff (lugs hit the cams and finishes cocking from there). Talk to them. It would be so much easier if the action was in hand

 

[Rook 6]

Had a similar experience with a Bix. In that instance it was incorrect sear engagement. Got a different sear height and the problem went away. It was a Rem clone with direct pins, no trigger hanger. A different trigger hanger might be the issue. BUT, you already have the correct answer: Call Kelbly’s on Mon.

 

[Keith Glasscock]

I agree with the analysis above. You have a trigger handoff issue. If you watch carefully, the cocking piece probably snaps forward a little bit at the hitch. That would signal that you need a different hanger.

Tactical style actions tend to (not sure about the Kelbys) have a lot of primary extraction that gets in the way of a clean handoff with little or no cock on close. Personally, I'd prefer cock on close over the hitch. For me, it is more comfortable to have a little more firing pin fall and cock on close with a slightly early handoff.

Unfortunately with the TriggerTech I have on my PRS rifle (Impact action), I have a pretty good hitch from that same cause, but haven't yet been able to find a longer trigger hanger to deal with the problem. It shoots well either way, but makes me nervous because it increases the risk of skipping the sear...

If you are feeling froggy, disassembling the firing pin assembly to check the thread engagement and friction between the shroud and bolt can improve feel and ES/SD *if* it has a tight spot in the threads (removed by lapping).

 

[AlNyhus]

Do you have a stock 700 trigger around to try?

 

[Kevin1990]

Do you have a stock 700 trigger around to try?

Unfortunately I do not. All I have is a diamond and primary. I also have a shilen BR trigger.

 

[AlNyhus]

Have you tried the Shilen?

 

[Kevin1990]

I agree with the analysis above. You have a trigger handoff issue. If you watch carefully, the cocking piece probably snaps forward a little bit at the hitch. That would signal that you need a different hanger.

Tactical style actions tend to (not sure about the Kelbys) have a lot of primary extraction that gets in the way of a clean handoff with little or no cock on close. Personally, I'd prefer cock on close over the hitch. For me, it is more comfortable to have a little more firing pin fall and cock on close with a slightly early handoff.

Unfortunately with the TriggerTech I have on my PRS rifle (Impact action), I have a pretty good hitch from that same cause, but haven't yet been able to find a longer trigger hanger to deal with the problem. It shoots well either way, but makes me nervous because it increases the risk of skipping the sear...

If you are feeling froggy, disassembling the firing pin assembly to check the thread engagement and friction between the shroud and bolt can improve feel and ES/SD *if* it has a tight spot in the threads (removed by lapping).

Dang, man. You know your stuff. The cocking piece is indeed coming forward, once I get over that area/ hitch. It’s actually quite noticeable.