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Thread: Bolt Lift

  1. #1
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    Bolt Lift

    I was watching the video online of Charles Huckeba shooting at the world championship a few years ago and it seems like his gun has a real light bolt lift. What are some steps to get a lighter bolt lift?

  2. #2
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    Aside from some work by a gunsmith you can reduce the powder charge or go to great lengths to produce a die that works well. I've had a few barrels that were easy peasy to extract cases and a few that were almost ridiculously difficult. Only one of the difficult barrels shot well enough to win. You need easy!

  3. #3
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    Thanks Wilber
    It seems even without a round in the chamber his rifle has a lighter bolt lift than mine. I assume the bolt carries the bulk of the responsibility for that and the trigger the lesser. Is that correct?
    Ted

  4. #4
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    Quote Originally Posted by TedH View Post
    Thanks Wilber
    It seems even without a round in the chamber his rifle has a lighter bolt lift than mine. I assume the bolt carries the bulk of the responsibility for that and the trigger the lesser. Is that correct?
    Ted
    New brass helps a lot. Or at the very least brass that has few firings.

    Difficult bolt lift due to heavy firing pin spring pressure is also a factor. I have found that my rifles shoot best with around 23 lbs of static pressure. That does contribute to a harder bolt lift. I have tried spring pressures as light as 16 lbs, and the groups open up. But the bolt was easy to lift.

  5. #5
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    I was just talking to charles today here at the cactus and I asked him about his actions and how he gets them working so smooth. He didn’t go into every detail but he did say that he works on the lugs and inbutments and then goes through the complete bolt. It’s a long process he said but the end results are rewording.

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  7. #7
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    That was a good video. Thanks

  8. #8
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    Taking this a different way.....

    While all answers are good, I feel maybe they aren't exactly what Ted's asking about. Jackie mentions running a lighter spring, which does IMO directly address Ted's question but maybe not all of it.

    Ted,

    IME there are several factors affecting bolt lift. But first let's define "bolt lift" to be sure we're talking of the same thing.

    To me "bolt lift" is the force required to cock the rifle. Nothing more, nothing less. Sticking/clicking/tight brass are different issues TO ME ....... but at the risk of offending others I'll share some of the things I've learned about what I'm calling bolt lift.

    To cock the firearm you must use the firing mechanism to "lift" about a 20-25lb weight about a quarter inch. I've often illustrated the firing cycle as "picture dropping a cinderblock onto the loaded round"....... most often this comes up in the "loading long for fireforming" dicussions, I say "REALLY??? So if you set a cinder block on your loaded round does the bullet move? Now lift it up a fuzz and DROP IT!" What I'm saying is, you have to do that much work to cock the firing pin back

    Remember the old 22's where you just pull back on the knob? That's direct cocking, no mechanical advantage. Very efficient but hard on the fingers.

    The firearms we use implement a cocking ramp where the action of rotating the handle of the rifle bolt drives a ramp or wedge under the cocking piece and lifts it into position. SAME WORK...... but "easier" because it's spread out. Just like rolling a barrel up a ramp into your truck VS dead-lifting it. The stroke available on the handle is generally somewhere between 60 and 90 degrees......

    For a baseline the Rem 700 (90* stroke) the ramp compresses the spring about 1/3 inch using a ramp about 1/2 inch long. A Cooper style 60 degree bolt lifts about the same amount but uses a shorter and therefore steeper ramp, maybe 1/3in long, whereas a Kelbly small bolt (90 degree lift) uses the longer 1/2 inch stroke but only lifts the firing pin 1/4 inch..... buncha' stuff going on here we won't cover but what you need to know is...... LESS PRESSURE required to lift the hannle.

    Now, to get a Rem 700 to act like the gun Charles is using is basically impossible but you CAN make it pretty good if you're a risk taker and/or willing (like I'm)..... but it ain't simple! It involves re-cutting the cocking ramp, mating the surfaces and re-timing the trigger for starters. Then a lighter spring, bushed bolt, skinnier firing pin.....I ain't going there in this thread.

    This is one reason a Cooper makes a crappy bench gun, you try cocking it like Charles is and you'll turn the gun over.

    Soooo, you start with a custom action. Now, what I do is probably different than what others would do but..... I start by checking the engagement of the cocking piece to the cocking ramp. I have dental supplies so I brush some dental pressure indicating paste onto the ramp (STOS works too, and other greases) and run 'er up. Look for bearing. Look to see how the surfaces are mated. Adjust to make the two surfaces match. Polish.

    Some folks like to use lapping compound..... or Flitz.... or whatever they're comfortable with to grind/smooth/polish the surfaces. The idea is to get the two surfaces mated so that the lubricant is spread evenly, no pressure points in the cycle.....

    And once the surfaces are properly synchronised you play with lubricants...... I ain't GOIN' there but suffice it to say this whole "how to lubricate SS" is a large subject. I'll suggest 'Hobo Oil' on the bolt body and Kelbly's/Borden's/Sinclair/STOS etc on the cocking ramp. STOS is a little light and doesn't last but one of my guns responds to it well.

    And then, you REALLY want it stress-free, you add a roller. I have a 90 degree 2" BAT 'M' with a roller cocking piece that makes Charles' gun look stiff.....


    So them's some of my thoughts..... hopefully stimulate conversation if nothing else because this is just the START of really getting 'er dun.


    Type of lube used inside and how it's applied..... polishing the firing pin, CHANGING the firing pin body....... changing the spring...... polishing the spring...... conditioning the spring, maybe even cooking in a lube..... keeping the inside "perfect" at all times.....polishing the threads on the shroud... the flats.......... how to lubricate the shroud......there's guys on here who've completely re-worked every moving surface and who use 6 different lubricants in different places.....

    could be an interesting thread if'n folks want it

  9. #9
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    Very informative and what I was looking for.
    Thanks

  10. #10
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    One important thing in chambering, polish the chamber surface while the barrel is still chucked up, then lightly grease the first few cases fired. The tool marks left by the reamer is really about 63 RMS, A chamber needs to be about 16 RMS or better. Really dry, degreased cases are sticky to break loose after firing.

    Then, what I do. For starters I have 5 Pandas all to exactly the same headspace. Then I chamber with a Jim Borden spec chambering reamer. This reamer is about 0.0007 over the "standard" JGS 1945 spec.

    Then I use a certain Harrell die. Linwood Harrell numbers his dies 1 thru 4, 4 being the tightest. The die I had him pick one out that would be a 4.5 or 5. Normally he would have polished this die out to a #4, the tightest. This super spec setup works fine for me. The extractor has to just "touch' the fired case to break it loose for extraction. All this, considering I fire a super hot load of Rl-10x where the velocity chronod at 3525 fps at 20 yards and QuickLOAD calculates the pressure at 73,500 PSI.

    Some of what I mentioned here may help you solve your sticky bolt lift problem. A perfectly tuned chambering should allow you to lift your bolt handle with just your index finger.


    .

  11. #11
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    An aspect of bolt lift Al

    also is the primary case extraction. If one is using really tight fitting cases that probably will add to the felt force need on initial opening. Just a thought.

  12. #12
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    Quote Originally Posted by FBecigneul View Post
    I'm probably exposing myself to criticism here. I enjoyed the video, but was left wondering. That appeared to be a Whidden die which I'm told are very good and are on the spendy side. If one is going to spend big $$ on a die, why wouldn't one get a die that fir the chamber properly? Why would I need another die, such as a ring die to do what the primary size die should have done? Really not trying to be a smartass, but inquiring minds want to know. Since I took Al's advice years ago and started having my reamers ground for "fat butt" chambers, my extraction problems have disappeared. I never have bolt click even with substantial loads. Pretty sure someone will chime in here and straighten me out, so I have my asbestos suit on.

    Rick

  13. #13
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    One of the aspects of sizing that is mostly ignored is chamber coverage vs. die coverage. What I mean is how far down from the shoulder of each the case makes contact. In the case of the chamber, headspace, gap space and chamfer size all come into play. Dies also have issues with now far down they size. It is common to have a very large chamfer or radius at the bottom of the die. If the die does not get far enough down on the case to properly size for the chamber, after a number of firings with hot load there will be extraction issues. The most common way to deal with this is to increase the sizing just above the part of the case that the die needs to reach, but is not, which slightly reduces the diameter of the part that the die cannot properly size. The point of the ring die in the video is to be able to reach farther down on the case without bumping the shoulder back too far. He had taken .035 off of the top of his shell holder to allow the die to reach down farther. There are a couple of FL dies that address this issue by separating die body position from bump setting. One is the Jones that has the shoulder built into its neck bushings and the other is the Warner. Both can be set so that the die body makes firm contact with the shell holder (which could be modified to allow more "reach"). I have a Harrell Vari-base die that has interchangeable base inserts. The inserts have almost no chamfer. I have cut down my shell holder by about .014. Some time back I had a case, that was used for load testing that developed an extraction problem, the classic click. Looking at my setup with the die set for proper shoulder bump I had a gap between the bottom of the insert and the shell holder. Taking a risk of damaging the fine insert threads, I unscrewed it a bit to the point where it just touched the modified shell holder, ran the case back up into the die, loaded the case and fired it. It extracted normally, without the click.
    That particular insert only reduced the diameter of the base of the case by just under .001.

  14. #14
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    No asbestos needed, Rick. First, if it is a copy of a Widden die that is unintentional and unknown. Second, if it is a copy of a Widden die, why does he see the need for such a die? These dies are honed to exacting dimensions in .0005 increments so, as you can see, they can correct microscopic problems. In time and after a number of firings, a case will expand to a point that your normal FL die will not correct after spring back. This die will reduce web dimensions to where the case will again properly chamber and, of course, extract. I thank you for the opportunity to explain that without being accused of unbridled advertising.
    I should have said shameless advertising, it is not.
    Last edited by FBecigneul; 03-10-2019 at 12:26 PM.

  15. #15
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    Quote Originally Posted by FBecigneul View Post
    No asbestos needed, Rick. First, if it is a copy of a Widden die that is unintentional and unknown. Second, if it is a copy of a Widden die, why does he see the need for such a die? These dies are honed to exacting dimensions in .0005 increments so, as you can see, they can correct microscopic problems. In time and after a number of firings, a case will expand to a point that your normal FL die will not correct after spring back. This die will reduce web dimensions to where the case will again properly chamber and, of course, extract. I thank you for the opportunity to explain that without being accused of unbridled advertising.
    I should have said shameless advertising, it is not.
    Thanks Francis & Boyd.
    I appreciate the explanation. I do have a set of the vari-base dies and most of my dies are Harrells, although I do have one Whidden. I do think I understand the problem as well as it's cause and several methods to solve it. This is clearly one way and I thank you for your time.

    Rick

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