Stevens bolt fix ?

[gotcha]

Hi Guys, Need some input from the "gurus". Stevens LA build. Trying methods to improve bolt cycling resistance. Have done the following: 1. reshaped cocking ramp w/ Cratex & dye-chem to get max contact of button through entire length of ramp. 2. installed Stockade bolt kit. 3. Lightly polished locking lug lead-in ramp & high spots on lug shelf. 4. lightly polished rear ring where bolt makes contact. 5. Dis-assembled bolt & polished ALL areas of movement greased & re-assembled. 6. gobbed valve grinding compound onto lug shelf & operated the bolt about 500 times........ Cocking much improved, but still not on par with my Remmys w/ short bolt handles. Sorry! I'm intrigued w/ Dolomites multi bearing bolt kit. The single bearing kit I've got just seems to squeeze all the lube out of the detent leaving it dry & dragging. Also interested in lighter firing pin spring (about 24 or 25 lbs) Lock time will be effected but by how many milli-seconds ? Anybody else wrestled w/ these "improvements" ? Any experienced input appreciated. Thanx, Dale

[geargrinder]

Sounds like you're off to a good start. All that's left to do is run a few hundred rounds through it. :)

[thomae]

Dale, Here's a simple explanation of what I did to fabricate a multi-bearing lift kit.

Background: This was simple for me because I own a small metalworking lathe and a dremel tool, however, it would have been possible without the lathe, by using a drill press.

1. I purchased the appropriate thrust bearing from Avid RC bearings (http://www.avidrc.com/product/13/thrust-bearings/). $3.00 each and reasonable shipping charges. I believe I purchased 5.
IIRC I purchased the 5 x 12 x 4 bearing (http://www.avidrc.com/product/13/thrust-bearings/192/5x12x4-Thrust-Bearing-F5-12M-thrust-bearings.html). In retrospect, I should have gotten the 6 x 12 x 4, but more on that later.
2. This bearing is in three pieces: the inside ball assembly with the steel cage and balls and the two outer races, grooved on one side, flat on the other.
3. Since the outside diameter of the races was just a bit too big to drop in to the bolt assembly (the center bearing assembly dropped right in), I clamped each race between two nuts on a threaded screw. I simply wanted the diameter tobe small enough to drop into the Stevens bolt assembly, so precision concentricity was not a concern. I turned it down bit by bit until it was small enough to fit in the bolt assembly. Note: It took me a while, but I figured out that the races are made of extremely hard steel. Carbon steel will not cut it, and TiN coated drill bits will not drill it. Carbide lathe tooling was able to cut it, but I took very small cuts.
4. Once the two raceways were small enough to drop in, I fabricated a spacer for the BAS (to go between the BAS and the bolt handle) I drilled out the center to fit over the BAS, machined the outer diameter to match the outer diameter of the BAS, and made the whole thing approximately 4mm thick, to match the thickness of the thrust bearing.
5. After that it was simply a matter of cleaning up the bearings and races with solvent and compressed air (gently!) to make sure there were no metal shavings trapped on/in and assembling everything.

6. For my newer Savage where the firing pin extends through the BAS, I simply chucked the races in the jaws of the lathe individually, and then, with the lathe turning slowly, used my dremel tool and a diamond grit straight bit to slowly work the inside diameter out to .25 inches to fit over the firing pin. In this second case, I used the dremel and diamond bit on the outside diameter as well, since I already had it out and chucked up. It still took a little while but I was not trying to go fast. Again, because of the way this all fits together, I was not worried about precision machining and exact tolerances, so grinding it down with the dremel was perfectly acceptable.

7. I believe this will also work on the Axis, but the bearing would go between the mainspring and the BAS.

8. The reason I suggested the 6 x 12 x 4 is that the inside hole would then be 6mm diameter so there would be less to grind off to fit around the firing pin on the axis and newer Savages with the protruding firing pin.

9. I put a drop of moly compound on the bearings when I assemble them and they are good to go.

10. Although I have more ball bearings, I have rolling resistance only, not metal against metal sliding resistance. I don't know if this is better than the single center point non-rotating bearing lift kit, but it certainly feels smoother/lighter to me. I did not do a calibrated test, so I don't know how much of the lightness stems from my psychological need to have made a difference with my handiwork. Give it a try. The only thing you can't do without a lathe is fabricate the spacer, but any machine could easily do that for you (and they could do steel instead of aluminum) for a reasonable price.

If any of this is not clear, please let me know. I can edit this post for clarity, and am happy to correspond and answer questions.

I do not say that this is better than any one else's method, but simply that this is how I figured out how to do this.

Disclaimer: I have not fired these rifles much since then, so I can't offer any thoughts about 1000-shot durability and the like.

I will admit that for me, figuring it out is much of the fun.

[pdog06]

gotcha,
When you installed the Stockade boltlift kit did you also shorten the rear bolt assembly screw? If not you have now added spring pressure due to the thickness of the lift kit. Stockade will say that due to manufacturing variances you dont need to shorten the screw, but the lift kit is approx. .112" thick(you need to measure from the bottom of the liftkit washer to the top of the bearing).
Not saying that you'll even notice the difference, but with all else you have done why counteract your progress? I can honestly say that by shortening the BAS's and installing the boltlift kits on mine, i could not tell very much of a difference by just cocking it by hand. I never tested it with a gauge or anything though.

The whole purpose of the lift kit is that the single bearing gives it the least amount of surface area to cock the action. IMO installing a multi bearing kit would just counteract that. Now if you have a newer action with the cocking indicator thru the BAS, then the multi bearing would be the only option.

[Rifleman4910]

My mod. 12 absolutely hates a clean barrel. Check your sights and DON'T clean!

[thomae]

pdog06 has some valid discussion points:



gotcha,
When you installed the Stockade boltlift kit did you also shorten the rear bolt assembly screw? If not you have now added spring pressure due to the thickness of the lift kit. Stockade will say that due to manufacturing variances you dont need to shorten the screw, but the lift kit is approx. .112" thick(you need to measure from the bottom of the liftkit washer to the top of the bearing).
Not saying that you'll even notice the difference, but with all else you have done why counteract your progress? I can honestly say that by shortening the BAS's and installing the boltlift kits on mine, i could not tell very much of a difference by just cocking it by hand. I never tested it with a gauge or anything though.


On my bolt lift modification, the washer/spacer between the BAS and the cocking handle serves the same functional purpose as shortening the BAS by the depth of the lift kit.

I think everyone would agree, that if you want the spring pressure to be the same as before the kit was installed, you should do one or the other. ;D



The whole purpose of the lift kit is that the single bearing gives it the least amount of surface area to cock the action. IMO installing a multi bearing kit would just counteract that. Now if you have a newer action with the cocking indicator thru the BAS, then the multi bearing would be the only option.


The thing to remember is that with a single bearing lift kit you have sliding resistance/friction of the actual contact area between the BAS and the single bearing surface. With ball bearings in a race, you have 9 bearings, but you have rolling resistance, which, for any given contact area is significantly less than sliding friction.

Is the single bearing sliding resistance greater or less than the 9 small rolling ball bearings in my lift kit? I have no idea, and no way of accurately measuring it, so I will neither claim one is better than the other nor argue the point. (Just to satisfy my curiosity, I may see if I can get someone in the Mechanical Engineering Department at my local University to figure it out and give me the calculations. )

[gotcha]

All considered, gear grinder may have the BEST advice ;D There are some great posts by dolomite on this subject including info from Sharp shooter comparing factory bolt lift to his tests w/ multi bearing "kit" he put together. Fred used a spring pressure gauge to document improvements. I'm still thinkin' that a lighter pressure FP spring might be of additional benefit. Wolff offers 3 weights for Remmy LA's but only 2 for Sav. The Sav. springs are either factory (28 lb.) or a heavier 32 or 34 lb. spring. I've got an inquiry into Wolff about possibility of making up a lighter spring. Got to be concerned about consistent ignition & lock time but Wolff does make a lighter spring for Rem.'s. I tend to favor multi ball "kits". When you try to spin a b-bearing on it's axis the spring pressure begins to force the lube out of the detent leading to increased friction. Don't have any proof to prove this theory except experimenting w/ my single bearing kit & "thinking" bolt lift becomes more difficult as lube dissipates. Re-lube bearing and find bolt lift lightens compared against other actions I have............. Has anyone ever tried to shorten a FP spring to make it lighter ??

[Samdweezel05]

Here we go again. :o

[gotcha]

Thanks Sam, Great input on the FP spring question. :-*

[thomae]

Don't know about shortening the firing pin spring. Perhaps the thing to do is to buy an extra one and try it, 1/4 turn by 1/4 turn.

The other way to lighten a spring is to sand the edge, essentially making the wire thinner. This also smooths the edge which is what rubs against the inside surface of the bolt sleeve (friction, anyone?).

People make lightweight Remington firing pins (Titanium? Unobtanium?) I wonder if anyone makes such for Savages.

I don't have an answer for you, but am simply thinking aloud.

[geargrinder]

I'm not going to get into the whole friction thing again. >:(

Removing coils from a spring increases its strength, not reducing.

[gotcha]

Geargrinder, I just swapped out a standard LA ejector spring for a .223 EJ sprng. (shorter) to reduce the distance the ejector launched a 6.5L case then, after trying, cut 1.5 coils off the the .223 spring & further reduced the launch to 3 to 4 in. ( from about 1.5 ft. w/ original spring) Before trying this I was concerned I might get MORE tension by shortening................ But it didn't work out that way. Just sayin'. :) Thomae: I hear ya'! We're all thinkin' out loud. Understand what yur sayin' about reducing diameter of wire. That might work. The FP springs being flat ground on either end eliminate the ability to just cut coils off ends. I'm wondering if you could take coils out of the middle & TIG or MIG weld back together w/o effecting spring temper ? Whaddayah think? ???

[dwm]

If you work the bolt fast and hard, and you won't have these problems; it will fix 90% of the Savage action feeding problems too ...

[thomae]

Thomae: I hear ya'! We're all thinkin' out loud. Understand what yur sayin' about reducing diameter of wire. That might work. The FP springs being flat ground on either end eliminate the ability to just cut coils off ends. I'm wondering if you could take coils out of the middle & TIG or MIG weld back together w/o effecting spring temper ? Whaddayah think? ???


I am not sure what I think :) , but I KNOW I do not have the skills/tools to do that.

Perhaps Wolff springs has a spring, perhaps not officially designated a Savage Firing Pin Spring, but with the right length, diameter and strength. I wonder if that question has been posed to them?

[Toyoda]

If you weld the spring it will loose its characteristics, and have to be heat treated. Not worth the trouble.