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View Full Version : Firing pin spring length.



338win
06-12-2017, 09:22 PM
Hey guys this is my first post and im not sure if this is the correct area. I have done a bunch of searches on firing pin spring length when it is compressed between the firing pin stop nut and the cocking nut. I have a model 11 in 308 winchester. This is a 4.410" action center feed. I picked it up used and the firing pin had .070" protrusion so i adjusted it to .041". Now that it is set the diatance between the nuts is 1.990" i read on the thread about firing pin protrusion on here it should be 1.900". Is this a big deal? The cocking nut is bottommed out so i have no more adjustment except the firing pin stop nut. What should i do? And yes it shoots just fine.

Robinhood
06-12-2017, 11:46 PM
How does it feel when you cock it? I don't know the official answer for you but the cocking pin should not be bottomed out at the bottom of the cocking ramp. Maybe .020 to .040 from the bottom. The shorter the spring setting, the more you cock... or over cock it.

You can go closer to the bottom but do not let the cocking pin hit the bottom of the ramp when firing. It should wiggle a little side to side before you put the BAS back in.

Scott Evans
06-13-2017, 12:16 AM
Spring length is secondary, and a result of the pin adjustments for both pin protrusion and cocking pin to bolt body clearance in fired position. You want the cocking pin to have 1-2mm clearance to the slot in the bolt body in the fired position, and your pin protrusion, then spring length is what it is. The initial bolt freeplay you feel when cocking after firing a round is the cocking pin to bolt body clearance.

338win
06-13-2017, 06:24 AM
Thank you. I checked again and took it apart again. There was a burr on the threads, cleaned it up and i was ablle to get the cocking peice down to where it should be. When in the decocked position with the bolt assembled i can wiggle the cocking pin.

Robinhood
06-13-2017, 08:08 AM
Thats it!

Texas10
06-14-2017, 12:06 AM
The instructions I got with the Nat Lambeth bolt lift kit http://pacifictoolandgauge.com/misc-savage-parts/1998-nat-lambeth-inspired-savage-bolt-accessory-kit-w-o-handle.html

State that Savage tends to adjust firing pins to over cock so that they are always reliable in the field. He advised to adjust the cocking pin to where it is about .080 from the bottom of the cocking ramp to reduce un-necessary bolt lift force. After shooting a while, you may need to reduce that gap as the spring weakens with age.

I have one of his kits in my 6mmBR, but the other 6 Savages have the 38 cal & ball bearing lift mod. They all work very well.

Robinhood
06-14-2017, 08:26 AM
The ramp or cocking ratio needs to be reduced at the factory and all the BS about stiff bolt lift would go away. I'm thinking about .200 or less. Any thoughts on this.

J.Baker
06-16-2017, 09:36 AM
The instructions I got with the Nat Lambeth bolt lift kit http://pacifictoolandgauge.com/misc-savage-parts/1998-nat-lambeth-inspired-savage-bolt-accessory-kit-w-o-handle.html

State that Savage tends to adjust firing pins to over cock so that they are always reliable in the field. He advised to adjust the cocking pin to where it is about .080 from the bottom of the cocking ramp to reduce un-necessary bolt lift force. After shooting a while, you may need to reduce that gap as the spring weakens with age.

I have one of his kits in my 6mmBR, but the other 6 Savages have the 38 cal & ball bearing lift mod. They all work very well.

Well right there's your first problem, you bought something Nat Lambeth had something to do with. Second problem is that you're listening to his advise.

Nat used to be a regular here back around 2005/2006, and at that time as he was trying to convince everyone he was an expert Savage gunsmith. He saw the Savage's were trending upward and he was hoping to sell himself as an expert here so he could capitalize on their newfound popularity. Didn't take long for myself and others to realize he didn't know as much as he thought he knew, and most of what he knew was wrong. He got pissed at Fred and I when we called him on it and that's when he stopped coming here and started spending all his time over to Accurate Shooter.

Having met and spent some time talking with him at the SHOT Show in the same time frame I can say he's a nice enough guy and very personable, but based on my experience he's more used car salesman than anything else.

Texas10
06-16-2017, 01:30 PM
Interesting comment, and perhaps a good example of the hazards of using the internet to expand ones knowledge. FWIW, his lift kit works fine. The one I have arrived in an action I purchased from a member here. I thought it a cute example of a machined part to replace the 38 cal mod, something that takes me about 10 minutes to make and install. So maybe it's a bit overboard, and not cost effective by comparison. Can't fault a guy for trying...

So this leaves the question of the cocking ramp and bolt lift, and what is your fix, besides spending a lot of coin and time at Freds?

As for timing an action, where can one go to uncover the details of what is involved, and how to accomplish it?

Inquiring minds want to know...

J.Baker
06-16-2017, 07:19 PM
The PT&G bolt lift kit is fine - they just copied Fred's original idea and put their own spin on it. Still does pretty much the same thing as Fred's original kit, it's just more expensive to make. You can't get much simpler or more effective than a detent ball and a sawed off .38 Spl. case, but there's always people out there who think they can reinvent the wheel.

Recutting the cocking ramp is part of the fix for the hard bolt lift, but if you don't have the proper jig to remove the right amount and cut the ramp to the proper angle you will accomplish little more than ruining a perfectly good bolt body. The other part is recutting the lug ramps in the front of the action to match the cocking ramp which means a CNC lathe and the smarts to write the program to cut them to what they need to be. Fred does both operations on his CNC lathe to ensure the angles and ramps are perfectly in time each and every time. It's not something you're going to accomplish with your dremel, a manual mill or some lapping compound.

As for the last question, you won't find specific details as Fred's not about to reveal his secrets. Why should he? He pioneered the timing of a Savage action. He's the one who spent the time doing the R&D to figure it out and learn what is needed and what doesn't work, and once he found the right combination he developed the tooling and programs to do it consistently. Maybe when he's ready to retire he'll sell off his secrets to a worthy successor, but I doubt you'll get them out of him before that.

The truing part is easy, anyone with a metal lathe and a little common sense can do that. It's getting the timing sorted that requires the expertise and you'll never get that without first enduring a lot of trial and error.

Scott Evans
06-17-2017, 12:00 AM
PT&G was in cahoots with your good buddy Nat on that kit. There was a falling out. Now they sell a watered down version.

J.Baker
06-17-2017, 09:54 AM
PT&G was in cahoots with your good buddy Nat on that kit. There was a falling out. Now they sell a watered down version.

Nat's probably the only reason PT&G has done anything with Savage's, and it's why most of the parts they offer have "issues." Neither of them knows Savage's well enough to know the tolerance ranges over the years to be able to design products that will function in guns from all generations. This is why so many people who have bought bolt bodies or bolt heads from them have had problems. They're also trying to apply Remington-thinking to Savage's which simply doesn't work. The "slop" in a Savage action is there by design and for a reason, so when you try to eliminate that slop by adding tight fitting precision parts you typically end up with more problems than solutions.