Results 1 to 24 of 24

Thread: Bolt Lift

  1. #1
    iamsniper1
    Guest

    Bolt Lift


    Thought about the 38 case and ball bearing trick,grinding the BAS seem to me a bad idea,
    had to be a better way,searching the net I came across a bolt lift mod that actually makes sense,
    the parts consist of 2 thrust washers and 6 ball bearing encased in nylon,a perfect fit in the bolt body,
    the BAS spacer you have to make yourself.
    Received the bearing kit,machined a spacer,installed, now I can open the bolt with the back of my hand
    with just a small amount of resistance and smooth as silk.
    Of all the bolt lift mods I've seen,you can't beat the BSA riding on 6 ball bearings and no mod to the BAS
    to boot.

  2. #2
    Dirknar
    Guest

    Re: Bolt Lift

    You should show pictures and explain acronyms, for the dummies like me.. ;D

  3. #3
    Basic Member geargrinder's Avatar
    Join Date
    Feb 2007
    Location
    Northern Nevada
    Age
    52
    Posts
    1,727

    Re: Bolt Lift

    Quote Originally Posted by iamsniper1
    Thought about the 38 case and ball bearing trick,grinding the BAS seem to me a bad idea,
    had to be a better way,searching the net I came across a bolt lift mod that actually makes sense,
    the parts consist of 2 thrust washers and 6 ball bearing encased in nylon,a perfect fit in the bolt body,
    the BAS spacer you have to make yourself.
    Received the bearing kit,machined a spacer,installed, now I can open the bolt with the back of my hand
    with just a small amount of resistance and smooth as silk.
    Of all the bolt lift mods I've seen,you can't beat the BSA riding on 6 ball bearings and no mod to the BAS
    to boot.
    So now you have the friction of six ball bearings.

    The 38 case and bearing only has one contact point.

    Why would you think grinding the BAS is a bad idea?
    "Muzzle velocity is a depreciating asset, not unlike a new car, but BC, like diamonds, is forever."-German A. Salazar

  4. #4
    Basic Member geargrinder's Avatar
    Join Date
    Feb 2007
    Location
    Northern Nevada
    Age
    52
    Posts
    1,727

    Re: Bolt Lift

    Quote Originally Posted by Dirknar
    You should show pictures and explain acronyms, for the dummies like me.. ;D
    BAS is Bolt Assembly Screw. It is the screw on the end of the bolt that holds the bolt handle on.
    "Muzzle velocity is a depreciating asset, not unlike a new car, but BC, like diamonds, is forever."-German A. Salazar

  5. #5
    Samdweezel05
    Guest

    Re: Bolt Lift

    Yes, please post up pictures so we can all see the 6 points of friction instead of the one with a 38spl case and one ball bearing. Grinding is only a bad idea if you screw it up.

  6. #6
    iamsniper1
    Guest

    Re: Bolt Lift

    "So now you have the friction of six ball bearings.

    The 38 case and bearing only has one contact point.

    Why would you think grinding the BAS is a bad idea?"

    With the 38 case,the BAS rides on a single center point.with the 6 bearings, the
    BAS's surface has full contact.

    Using the 38 case and single bearing,the BAS usually has to be ground to make up for the 38 case and bearing,
    If the case and bearing are removed,the BAS is now to short for %100 function of the firing pin.

    As far as 6 friction points,I use a white grease that I use on my M1 Grand and M1A.(military uses this stuff)
    the size of the spacer keeps the BAS from mashing down on the bearings,yet full function of the firing pin.

  7. #7
    Basic Member geargrinder's Avatar
    Join Date
    Feb 2007
    Location
    Northern Nevada
    Age
    52
    Posts
    1,727

    Re: Bolt Lift

    Quote Originally Posted by iamsniper1

    With the 38 case,the BAS rides on a single center point.with the 6 bearings, the
    BAS's surface has full contact. It

    Using the 38 case and single bearing,the BAS usually has to be ground to make up for the 38 case and bearing,
    If the case and bearing are removed,the BAS is now to short for %100 function of the firing pin.

    As far as 6 friction points,I use a white grease that I use on my M1 Grand and M1A.(military uses this stuff)
    the size of the spacer keeps the BAS from mashing down on the bearings,yet full function of the firing pin.
    Riding on the single center point is what gets rid of all the friction. The best way to reduce the friction between the to is to reduce the amount of contact between them. That's why one point of contact is better than six which is still better than the cocking sleeve dragging directly on the BAS. It's going to be that way no matter what grease you use.

    You don't have to grind the BAS at all. You could use a spacer with either method. Why would you want to remove the bearing setup? BAS's are cheap if I ever wanted it back to 100%.

    I'm not trying to be a jerk. I'm just trying to point out the facts of what is going on. You solution works works better than factory and you have not permanently modified anything. That doesn't make it better that the other way nor does it make the other way a bad idea.




    "Muzzle velocity is a depreciating asset, not unlike a new car, but BC, like diamonds, is forever."-German A. Salazar

  8. #8
    Super Moderator Blue Avenger's Avatar
    Join Date
    Dec 2006
    Location
    Minnesota
    Age
    65
    Posts
    2,965

    Re: Bolt Lift

    machining the screw keeps it flat, as might a well made spacer. I have not met the person that could "grind" a screw flat and parallel enough to have equal pressure on 6 bearings. With the cocking indicator on some guns, you do need something of that sort though.


    .223 Rem AI, .22-250 AI, .220 Swift AI .243 Win AI, .6mm Rem AI, .257 Rob AI, .25-06 AI, 6.5x300wsm .30-06 AI, .270 STW, 7mm STW, 28 nosler, .416 Taylor

  9. #9
    iamsniper1
    Guest

    Re: Bolt Lift

    Quote Originally Posted by Blue Avenger
    machining the screw keeps it flat, as might a well made spacer. I have not met the person that could "grind" a screw flat and parallel enough to have equal pressure on 6 bearings. With the cocking indicator on some guns, you do need something of that sort though.


    You are absolutely right about machining the BAS,(key word-machining)some people who have used the 38 case nod
    thought they could just get away with grinding/filing with no concept of what they were doing to the BAS,including
    drilling the detent for the bearing on the BAS which has to be absolute dead center.
    One poster stated the BAS was cheap,so if he screwed up his BAS,he would buy another,how many bolt screws would be wasted?
    Without access to a lathe/milling machine the home brew guy is fighting a losing battle grinding/filing the BAS.
    A BAS cost about 5/6 dollars+ mod,price of the thrust bearing kit-$1.87-spacer-20 cents,no mods to the BAS-priceless.

  10. #10
    Basic Member geargrinder's Avatar
    Join Date
    Feb 2007
    Location
    Northern Nevada
    Age
    52
    Posts
    1,727

    Re: Bolt Lift

    Quote Originally Posted by iamsniper1


    You are absolutely right about machining the BAS,(key word-machining)some people who have used the 38 case nod
    thought they could just get away with grinding/filing with no concept of what they were doing to the BAS,including
    drilling the detent for the bearing on the BAS which has to be absolute dead center.
    One poster stated the BAS was cheap,so if he screwed up his BAS,he would buy another,how many bolt screws would be wasted?
    Without access to a lathe/milling machine the home brew guy is fighting a losing battle grinding/filing the BAS.
    A BAS cost about 5/6 dollars+ mod,price of the thrust bearing kit-$1.87-spacer-20 cents,no mods to the BAS-priceless.
    You are still not getting it.

    The BAS does not have to be ground/machined/filed perfectly parallel to the end of the cocking sleeve with the case and bearing. The centered single point of contact allows for plenty of angular misalignment. The only critical measurement is shortening the BAS by the thickness of the case rim and the bearing protrusion.

    Drilling a detent? I've never seen anyone do this. That would be a bad idea. There is nothing to detent. The bearing is rotating around a fixed point.

    I was relating the cost of the BAS to the cost of my time. Even when I'm not at work my time has value. It the true cost of your spacer 20 cents? My BAS only cost money if I waste one.

    How many screws wasted? I think I've done about 20 BAS's. I haven't screwed one up yet.

    Just because your process is more complex and you are doing a bunch more work doesn't make better than a simple quick fix.


    "Muzzle velocity is a depreciating asset, not unlike a new car, but BC, like diamonds, is forever."-German A. Salazar

  11. #11
    iamsniper1
    Guest

    Re: Bolt Lift

    "Just because your process is more complex and you are doing a bunch more work doesn't make better than a simple quick fix"

    Unscrew BAS,install bearing kit,add spacer,install BAS,done.
    What is so complex about that?
    5/10 minutes work,done.
    Talk about work,mod 38 case,measure case,inlarge primer cup,install 5/32 ball bearing(if you have one),
    BAS either fits right or has to be trued for proper function of firing pin.Now,that's work!


  12. #12
    Samdweezel05
    Guest

    Re: Bolt Lift

    I have no issue with the work part of it as I have a lathe and a milling machine. I am still trying to figure out how 6 points of friction on the outside edge of the BAS (drag) is better than a single point of friction at the rotating center of the BAS (rotation).

  13. #13
    Basic Member geargrinder's Avatar
    Join Date
    Feb 2007
    Location
    Northern Nevada
    Age
    52
    Posts
    1,727

    Re: Bolt Lift

    Quote Originally Posted by iamsniper1
    "Just because your process is more complex and you are doing a bunch more work doesn't make better than a simple quick fix"

    Unscrew BAS,install bearing kit,add spacer,install BAS,done.
    What is so complex about that?
    5/10 minutes work,done.
    Talk about work,mod 38 case,measure case,inlarge primer cup,install 5/32 ball bearing(if you have one),
    BAS either fits right or has to be trued for proper function of firing pin.Now,that's work!

    I can do it all in the same amount of time. I can go to the hardware store and get all my parts. I can do it all with simple hand tools without firing up any of my lathes or mills.

    We're getting off into the weeds. Go ahead and answer Sam's question. How does your way have less friction than the single bearing way? Greg's picture shows 11 bearings. I bet that bolt almost cocks itself. ;D

    "Muzzle velocity is a depreciating asset, not unlike a new car, but BC, like diamonds, is forever."-German A. Salazar

  14. #14
    Maxxwell86
    Guest

    Re: Bolt Lift

    Any one have a pic of the .38 case mod?

  15. #15
    Basic Member geargrinder's Avatar
    Join Date
    Feb 2007
    Location
    Northern Nevada
    Age
    52
    Posts
    1,727

    Re: Bolt Lift

    Quote Originally Posted by Maxxwell86
    Any one have a pic of the .38 case mod?
    http://savageshooters.com/SavageForu...c,30233.0.html
    "Muzzle velocity is a depreciating asset, not unlike a new car, but BC, like diamonds, is forever."-German A. Salazar

  16. #16
    Basic Member
    Join Date
    Dec 2006
    Age
    53
    Posts
    127

    Re: Bolt Lift

    Harvested from an Australian forum ...





    BAS was polished is all.

    Further value was gained from this modification ... cocking piece replaced by one incorporating a roller bearing.
    [img width=551 height=450]http://bcrc.iinet.net.au/pictures/bolt_lift/Bolt6.jpg[/img]

    Both mods meant an LRPV suffered from nil destabilisation when lifting the bolt whilst in the bags.
    Cheers...
    Con

  17. #17
    Team Savage jonbearman's Avatar
    Join Date
    May 2010
    Location
    NY
    Age
    66
    Posts
    1,385

    Re: Bolt Lift

    I center drill the bas for a perfect single point of contact and I turn the bas screw down .112 thou and it makes cocking sweet with no misfires.
    Willing to give back for what the sport has done for me!

  18. #18
    Basic Member
    Join Date
    Dec 2006
    Posts
    3,355

    Re: Bolt Lift

    I promised myself I would not interfere anymore in these threds that seemed to have everybody worked up, but now I am going to intervene. It doesn't bother me that you want to tinker and make the world better, however your methods are what got me upset. I apologize for coming off unprofessional, but maybe the following will cast some light where I come from.

    Your first idea was very questionable from a safety standpoint, and I am glad that you 86'd it. It raised more questions than answers. Your second idea is more favorable, but it is hardly fresh, as I devised the same thing as soon as the new cocking indicator models came out on the American Classics 2 years ago.



    I never bothered posting a picture, frankly because not many were out yet and there was no immediate need. This version uses 11- 3/32" ball bearings in a custom made race.

    You have created quite a stir amongst those who want to learn more about this and others who question what your role is. Your "testers" have no established protocol or scope of parameters to lend any credibility to what's going on. It's like the blind leading the blind. Like anything scientific, there are proper and accepted ways to experiment and collect data. I can see where you are lacking in this department and I have decided before this thing gets ugly, I will help you out.

    In grade school we had science fairs that were based on experiments of the student's choice, but the format was always the same.This is how is was laid out:

    1. OBJECTIVE: decribe what you are attempting to acheive.
    2. HYPOTHESIS: decribe what you think will happen with limited observation.
    3. METHODS: describe your methods for testing and the equipment you used.
    4. RESULTS: report what actually happened supported with data.
    5. SUMMARY: summarize the situation explaining why, or why not, the results were different than what was hypothesised.

    Over the years I have gathered more than enough data for this, so I will lead by example.

    OBJECTIVE: to establish a way to reduce the cocking effort required to cycle/cock a Savage rifle by reducing friction.

    HYPOTHESIS: by reducing the friction on the bolt assembly screw where it contacts the cocking sleeve on the periphery can reduce the amount of efforts needed to cock and close the bolt.

    METHODS: I will use ball bearings as a means of friction reduction and will collect data using torque values gathered with a Sturtevant Richmont inch/lb beam style torque wrench, model M 50-1. To eliminate as much human error as possible, I will chuck the action in a lathe chuck and support the torque wrench with a solid support to get consistant reading.All tests will use a bolt assembly screw shortened the same amount of what the bearing will take up.



    RESULTS: The data collected here was derived from 36 different actions representing a cross section obtained from specimens manufactured from approximately 1997 to 2008. These numbers represent the average of operations.

    COCKING EFFORT: 22.30 in/lbs.
    CLOSING EFFORT: 13.5 in/lbs.
    OPENING EFFORT(already cocked): 17.9 in/lbs.


    Notes: The hardest to cycle measured in @30 in/lbs, the esiest @ 18 in/lbs. I consider these to be the extreme, with most being in the 20 in/lbs range.

    The following data was collected from 1 specimen using the 2 types of bearings to reduce friction.

    Efforts involved in cycling operation
    Observations made on a Savage model 116 serial# G893xxx
    1.operation. 2.before mod(stock). 3.w/single centered ball bearing. 4.w/ thrust bearing. 5.Trued&timed w/no mod. 6.Trued&timed w/thrust bearing. 7.Trued &timed w/single centered ball bearing.[/color]

    Operation Before Mod (stock) Single Centered Ball Bearing Mod Thrust Bearing Mod T&T with No Mod T&T with Thurst Bearing Mod T&T with Single Centered Ball Bearing Mod
    Cocking Effort 20 18 19 14 13 12
    Closing Effort 16 14 15 10 8 8
    Re-open Effort 16 14 15 12 10 9

    SUMMARY: These tests conclude that a single centered ball bearing reduces more friction that multiple ball thrust bearing. Other factors besides friction affect the efforts of cycling due to the variant geometry of the various components of the fire control system. This test does not address the several other points of friction that also contribute to cycling efforts. The trued & timed action was included in this test to demonstrate the the consistency of what a single centered ball would reduce in friction only. It appears through this test and many others that I have checked to reduce all the cycling efforts only by 2 in/lbs.

    This data was collected long before I publicly shared the idea of the ".38 case and ball bearing tip". Before that, I made the first ones turning a steel "case" and drilled it for a ball bearing. Although it was more precise, it did not work any better than an old .357 case cut down and a ball bearing epoxied in the primer pocket. It was alot less work, not to mention cheap. As far as shortening the bolt assembly screw, it is less work than fabricating a spacer of specific size, although the spacer will work.

    These are my findings; like it or not, you don't have to take my word for it, so feel free to do what ever you want. It took quite some time for me to dig out all my notes and compile this, so I hope you appreciate it.
    "As long as there's lead in the air....there's still hope.."

  19. #19
    iamsniper1
    Guest

    Re: Bolt Lift

    Sharpshooter's post is way to long to quote here,however after reading the entire post
    I can appreciate his time and effort he put into his experiments concerning friction
    between a single bearing versus multi bearings.
    In between posting here,I did the 38 case mod although I did not alter the BAS,
    to make this post short,I reverted back to my multi bearing mod because to me in
    my rifle,using my bolt,using my multi bearing mod,my rifle cocking/decocking is much quicker and smoother
    than using the 38 case mod.
    Preference is the key word,whatever works for you.
    Of course this is just my opinion,I may be wrong.

  20. #20
    bgc
    Guest

    Re: Bolt Lift

    Déjà vu

  21. #21
    Basic Member
    Join Date
    Oct 2007
    Posts
    555

    Re: Bolt Lift

    Sounds similar to my post from a year ago.

    http://savageshooters.com/SavageForu...c,30658.0.html.

    Dolomite

  22. #22
    Basic Member
    Join Date
    Feb 2008
    Posts
    235

    Re: Bolt Lift

    I don't know why nobody else came up with this but........i;m putting on a bolt handle likr the one in the picture of the inch pound test...one that long would definitely make opening easier!!!!!!!!!!!!!! wait, thats a torque wrench, not a bolt handle, never mind, cancel that last thought....thought i had it whipped! rsbhunter
    If you stand for nothing, Then you'll fall for anything!

  23. #23
    thomae
    Guest

    Re: Bolt Lift

    Quote Originally Posted by Samdweezel05
    I have no issue with the work part of it as I have a lathe and a milling machine. I am still trying to figure out how 6 points of friction on the outside edge of the BAS (drag) is better than a single point of friction at the rotating center of the BAS (rotation).
    Remember the bearings, although six points of contact have primarily only rolling friction which is much less than static friction on an equivalent contact surface (I am not saying that one bearing is the equivalent contacts surface as six bearings).

    The 38 special with the ball in the middle has static rubbing friction, which is significantly more than rolling friction. Is it 6 times more? I could guess, but the answer is that I don't know.

    I do not say that one has less friction than the other, and unless one is a mechanical engineer with specific, hypersensitive measuring equipment (or knows all the appropriate equations from a M.E. textbook) we can only guess at which one has less friction.

    Sharpshooter did the closest thing to a scientific test and came up with one conclusion based on his results. Wonderful. Thank you Sharpshooter for your detailed explanation of your methodology.

    Instead of arguing, how about we acknowledge that there are (at least) two ways to skin this cat and whichever works for each one of us would be the appropriate one to use.

    If one shooter prefers one bolt lift friction reduction method and another poster prefers another method, great. Why is that a problem?
    Personally I may try them both since I am a tinkerer.

    Your mileage may vary, and what works for me may not be what works for you...that's ok.

    Remember, we are here to help each other out.

    None of us (yes, I include ME in that "us.") knows everything. Let's all try to keep an open mind and actually listen to what others are saying.



    All the best,
    Thomae

  24. #24
    r29l20
    Guest

    Re: Bolt Lift

    Well said, thank you. :)

Similar Threads

  1. Bolt Lift - Savage 116 Trophy Hunter with newer (axis) bolt
    By Camar068 in forum Axis Series Rifles
    Replies: 9
    Last Post: 02-02-2016, 08:35 PM
  2. Bolt lift mod
    By Bolt gunner in forum 110-Series Rifles
    Replies: 3
    Last Post: 02-14-2015, 05:37 PM
  3. Mark I/II/93R: KRG Bolt Lift
    By UncleSarge58 in forum Savage & Stevens Rimfire Rifles
    Replies: 1
    Last Post: 04-18-2014, 04:13 PM
  4. Bolt Lift Kit
    By bbradford71 in forum 110-Series Rifles
    Replies: 14
    Last Post: 01-03-2014, 12:11 PM
  5. What is a bolt lift kit?
    By scottkr in forum 110-Series Rifles
    Replies: 7
    Last Post: 02-19-2010, 01:39 AM

Members who have read this thread in the last 1 days: 0

There are no members to list at the moment.

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •