RV's Savage Bolt Lift Mod

[Rocketvapor]

Savage probably has the spring force UP to compensate for pin fall.
But I agree with many that think the factory spring is "oversprung".
They kicked up spring force on the new type, non adjustable pin to"eliminate problems".

Just remember, I am a "Hobbyist" not a Savage Expert.

 

[Rocketvapor]

New Cheaper Lift Kit. Adjustable for preload.
You need a New Style BAS,
and Thrust Bearing Kits, From China, eBay, 10mm X 4mm, 10 for less than $10,

10pcs I/D 3mm To 10mm Miniature Axial Ball Flat Washers Thrust Bearings ABEC1 | eBay

Accuracy Class:ABEC1. Product Item: Miniature Axial Ball Flat Washers Thrust Bearings 3-Parts ABEC-1. One Bearing Set:(2 steel races + one balls cage). All products are quality checked. Otherwise deal is final.

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And a 38spl head, drilled, NO ball.

To increase spring preload or decrease preload (requires shaving New Style BAS).


Shave BAS if required, stack Thrust Bearings for internal length.
Gives access to Cocking Pin through BAS for Pin Fall measurement.

 

[Rocketvapor]

PIN FALL using new style BAS and shims with a hole for depth gauge through the BAS
Started with a 10660 Commander Flat Wound Spring,
Pin Protrusion 0.038" Pin Length 3.548"
3.548 Pin Length
3.371 Depth to pin on cocking notch
3.601 Depth to pin on Bolt Head
0.230 Pin Fall, notch to Bolt Head

Shortened Pin to 3.467" (-0.081)
3.467 Pin Length
3.371 Depth to pin on cocking notch
3.680 Depth to pin on Bolt Head
0.309 Pin Fall, notch to Bolt Head
Cocking pin very close to bottom of cocking slot but floating.

Note that some measurements don't add up perfectly, Mostly measurement feel with the Starrett depth mic.
Had to push up on Cocking pin for both pin lengths to remove slack when measuring at bottom.
Pin was under pressure at the top but floating at the bottom.
Will have to try with bolt in action to get decocking from notch to sear hold.

 

[Rocketvapor]

Don't have an issue with brass extraction on the wife's Savage but just in case I glued a thin shim on the forward side of the rear baffle. 16 thou, about half the thickness I could have gone.
Will it help? Who knows
It's on an extra baffle anyway.




If I need more thickness I'll just gold plate it and have 0.016007"

 

[Rocketvapor]

With a week until the next match, time to play with the wife's Savage.
Tried to measure Primary Extraction with a few different baffles.
Got sort of good readings. Ended up lapping the thickest down a little as I felt maybe some drag engaging the bolt lugs.
Measurements probably within a few thousandths
Got 0.060" with stock baffle A from bolt closed to open,
0.068" with baffle B
0.075" with baffle C


Lapped Baffle "C" down to 0.478" as it felt like timing with bolt head lugs might be a little tight.
P.E. now measures 0.070"

"C" Baffle

 

[Rocketvapor]

One more bolt lift mod (not my idea) that might help a tiny bit.
The rear baffle has a 2 ball and spring setup to hold the baffle in a bolt body slot when handle is FULL up.
Dragging the ball, under spring pressure out of the slot and dragging it around the bolt as you move the handle just has to contribute some friction to bolt rotational movement. Take the bolt out and move the baffle around to feel what I am talking about. I removed the balls and spring and filed both ends a little, shortening the spring by about 0.025".
Put it all back together and OH BOY, a teenie tiny bit less drag, maybe, sort of

Note that this is a gallon bag mod.
Ran a test with my Digital Torque Wrench.
Same bolt, lubricated.
Bolt rotation, cocked, with unmodified baffle, UP, read 3.24 in lbs just through the free rotation before contacting PE ramp.
Modified spring baffle would not trigger the low limit of 2.66 in lbs.

Modified 2nd baffle with 0.040" off spring. Feels lighter but less than the Torque Wrench will resister.

 

[Rocketvapor]

Summary of mods done to wife's Savage 22N, some things tried at beginning of this thread have been discarded. Non-adjustable firing pin is OUT.
The hole thru the BAS and 38Spl (the one withe stack of bearing races) was to measure pin fall, decocking from the rear, The Carbide Micrometer insert and Ceramic ball is the current condition.

Summary of mods to date:
RV's Bolt Lift Mod.
Commander flat wound spring.
Firing pin shortened to increase Pin Fall, increase Spring Preload by drilling out a couple threads.
Cocking notch and holding shelf modified.
About 0.300" from shelf at top of ramp, less about 0.040" decocking coming off shelf to Sear Hold position, plus 0.042" Pin Protrusion.
Shims added to rear Baffle for increased Primary Extraction.
Rear Baffle detent spring shortened 0.040" to reduce drag.
Head Space set a tiny bit shorter than Go gage for shorter Nosler brass.
General smooth and blend of bolt parts.

The Accutrigger stills seems to be doing good for her.
Springs and shims give a little less than 2 oz blade, 7 oz total pull.
Pictures scattered in this thread should show all the mods.

Will do some more torque measurements on bolt lift, cocked and uncocked with maybe a video.

 

[95GTSpeedDemon]

Do you know which EGW spring works for a LA 110?