R700/Jewell trigger, timing issue?

[Alex Wheeler]

If all is well and correct with the firing pin/cocking piece/bolt, I would think that the problem lies within the trigger that you say is "2nd hand".

I have experienced before a jewell trigger that was used and had been sitting in a safe for 5 years. The trigger would not reset and the firing pin would follow the bolt back down as it was rotated closed.

After a good cleaning with brake cleaner and lighter fluid to remove the old gummy residue inside the trigger, all was well.

I understand that yours will reset if you pull the bolt back a small amount, making me think that your 2nd hand trigger could be just a slight bit sticky inside....or not. Goodluck!!!

It is normal to have to pull the bolt back a little to allow the trigger to reset on and action that has cock on close.

 

[fastnflat1]

You have to measure right when the top lever touches the cocking piece and again just after the cock on close is done, subtract the amount the shroud backs up do to thread pitch and the angle at which the two measurements were taken. That is how much cock on close you have. Thats how much need to be removed from the cocking piece and how much pin fall you will lose. I have done a lot of Remingtons, the depth the the cocking cam prevents move than about .210 of pin fall if setup without cock on close. Thats what it all comes down to the cocking cams on every bolt out there except a Borden and some PTGs do not have the depth to allow smooth close AND enough pin fall. Thats what I do, I recut the cocking cam helix. Thats why timing and action is not as simple as grinding a cocking piece. My advise is, unless you are willing to recut the cocking cam to the correct angle and depth, live with the cock on close. You will experience accuracy issues in the .220-.230 pin fall range. I have cured accuracy issues due to this, it is a fact.

Cock on close is an obnoxious feeling. But to me, it feels terrible whether you have .040" or .010". Simply reducing it doesnt really help the feel that much, you have to eliminate it. Honestly if you are gonna have cock on close I prefer a lot of it right from the start, at least its is smooth (even if its stiff) that way without the clunkyness.

So to clarify my understanding of "the whole job"...If the depth of the cocking cam helix is recut to gain optimal pin fall (.240"), then firing pin protrusion is also increased?

Therefore you could possibly have a pin protrusion of .085" if the previous protrusion was .055"???

So really, unless the the firing pin tip is shortened say .030", the sought after fall increase isnt gained???

I have seen where the helix cut is deep enough but the front shoulder of the firing pin bottoms out inside the bolt first. In this case do you turn back the firing pin shoulder or bore the bolt ID deeper???

 

[Fast14riot]

Rule #1, always modify the cheaper part. Shorten the pin before boring bolt body.

 

[rayjay]

Rule #1, always modify the cheaper part. Shorten the pin before boring bolt body.

Here is a quick and easy way to experiment.

http://pacifictoolandgauge.com/remi...0-bench-rest-cocking-piece-push-back-030.html

 

[fastnflat1]

No, you do not modify the pin stop. Protrusion does not change. I have videos on the subject and have posted a lot on this. After you remove the cock on close you have to re-gain the lost pin fall. It requires cutting the cocking cam helix, modifying the pin and cocking piece. I developed this method and the tooling needed to do it. I am the only one who does this. I am glad to help and explain what I do but I wont be posting a step by step tutorial online either I am always glad to answer questions if you would prefer to call.

From my recent experience...

Protrusion DOES change!!
After removing cock on close, you say man should re-gain that lost fall distance.... when you re-cut the cocking helix in bolt to achieve that, you are also increasing the pin protrusion by letting the pin advance farther into the bolt. Not a big deal, just modify the pin to correct it and all is well.

 

[Alex Wheeler]

From my recent experience...

Protrusion DOES change!!
After removing cock on close, you say man should re-gain that lost fall distance.... when you re-cut the cocking helix in bolt to achieve that, you are also increasing the pin protrusion by letting the pin advance farther into the bolt. Not a big deal, just modify the pin to correct it and all is well.

Firing pin stops when the collar contacts the inside of the bolt. We are not modifying this collar thus not changing protrusion. I do this for a living. It can be confusing. The helix is never deep enough on a Remington.

 

[Fast14riot]

I guess I should qualify the trigger, when I say second hand, I bought it with the barreled action from a member here and trust their word.

It is clean. Cock on close means the sear and cocking piece are overlapped when bolt is cocked, until the bolt is moved aft to clear the sear, leaving some forward travel left to close the bolt completely. I have read many of Alex's detailed posts on the topic and combined with a couple more bits of info in this thread I now see fully how the system is flawed according to us, but reliable and safe according to the lawyers.

I am not set up to cut the helix properly, but now I know exactly what must be done if I have someone other than Alex (not sure why someone other than you would be chosen, but just in case) work on my action. It's also important to me to know exactly what questions to ask a smith or if I ever pick up a used modified 700 action I can qualify it.

Alex, thank you for sharing your hard earned knowledge on the topic.

 

[fastnflat1]

Firing pin stops when the collar contacts the inside of the bolt. We are not modifying this collar thus not changing protrusion. I do this for a living. You have not grasped the concept yet. It can be confusing. The helix is never deep enough on a Remington.

I fully understand the concept. I timed 2 of my own lastnight and am very pleased with the results. And yes I'm picky lol Only 1 needed the helix re-cut. It was a remington bolt, the other a PTG. Both of them had to have the collar turned back, which lead to increased pin protrusion. Simple fix though.

The only other way to re-gain that pin fall is to shorten the other end of the firing pin and drill a new hole to pin on the cocking piece. Which most likely will shorten protrusion....

These were remington model sevens, if it matters....

Im not trying to start a pissing match and dont want to discount anyones knowledge, work or reputation. I found this thread interesting and after some deep thought on the subject i jumped in head first and tackled a couple of my own. I may not have done it exactly like the "professionals" but im pleased with my results and learned a bit in the process.

Goodnight

 

[Jay Christopherson]

Yes, shortening the pin and re drilling the hole is how its done, and NO that does not effect protrusion. Be careful turning those collars, it can create other issues aside from protrusion. Theres a lot going on at the same time and changing one thing effects another. Think it all through and make sure you didnt create a new problem. Good luck.

If you shorten the collar, wouldn't you need to make sure that the cocking piece is not bottoming out on the bolt when the trigger releases? (I might not have the correctly terminology, but hopefully my meaning is clear).

 

[Alex Wheeler]

If you shorten the collar, wouldn't you need to make sure that the cocking piece is not bottoming out on the bolt when the trigger releases? (I might not have the correctly terminology, but hopefully my meaning is clear).

Yes that would be one of many places to look.

 

[butchlambert]

I just had sticker shock that the PTG cocking pieces are $27.

Pretty cheap! Have you machined one?

 

[rayjay]

Pretty cheap! Have you machined one?

That was the Midway price. The PTG price is much better I just remember paying about $35 for the complete PTG firing pin assy [ prolly 10 years ago ;0

 

[DLG]

What your seeing is normal. Its how the action is designed. If you eliminate cock on close you will not have this. But if you eliminate cock on close on a rem 700 (without doing the whole job) you will not have enough fall. Maybe .210" Your math or measurements are off.

So if you increase firing pin fall from .180 to .240 does that decrease pin strike energy? And if so how do you increase it and how much is enough?