Limbsaver on HS Precision

Discussion in 'Gunsmithing' started by tayhot, Oct 26, 2012.

  1. tayhot

    tayhot Well-Known Member

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    How difficult is it to install a Limbsaver pad on HS Precision stock? What Limbsaver part number would be needed?
     
  2. J E Custom

    J E Custom Well-Known Member

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    The problem with the limb saver is that it cant be ground/sanded to match the stock if it is the gel
    type so you have to find one that fits perfict without alteration.

    limb saver makes one that can be sanded but it is solid.

    I like the Pachmayer Decelerator because you can get them in 1/2'' or 1'' thicknesses.

    also some of the HS stocks have glued on recoil pads and dont have any bosses for the screws.

    J E CUSTOM
     

  3. shortgrass

    shortgrass Well-Known Member

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    +1 for the Pachmyr Decelerator
     
  4. Clark

    Clark Well-Known Member

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    Most glue on the Limbsaver. Not me. I epoxy in a Pine plug and screw the pad to the plug.

    The Pachmayr XLT is a weak sister compared to the Limbsaver for recoil reduction.

    I don't grind down the grind to fit pads, but leave the full size for more pad to shoulder connection area. The reveal is covered with a stock pad
    Triad Tactical, Inc.*::*Triad Tactical*::*All Triad Stock Packs*::*Triad Stock Pack

    I am shooting prone from a bi pod with a light weight 10 pound hunting rifle with bipod, scope, sling, rear bag, and ammo. I leave the stock pull much longer than a normal stock because of the prone shooting.

    I am shooting 7mmRemMag 150 gr at 3375 fps.
    I feel no pain at all from recoil.

    What does it all mean?
    It gets down to function vs appearance, and I am not building jewelry for women, I am building tools for men.
     
  5. Clark

    Clark Well-Known Member

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    [​IMG]
    [​IMG]
     
  6. Edd

    Edd Well-Known Member

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    Lousy workmanship is one of my pet peeves so maybe I should apologize for the following in advance.

    Based on those pictures, I'm having a tough time believing you are serious. But if you are, what it means is you are a hack of a craftsman. A person doesn't have to choose between function and appearance on a recoil pad, you can have both. You aren't building tools, you are cobbling butt pads.

    Also, if you are shooting 150 gr bullets at 3375fps, you probably need a lesson in reloading too.
     
  7. Clark

    Clark Well-Known Member

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    I have designed products for many companies, and some of them have special sections for those who design the appearance. Guys who work in those areas have feminine voices and bring in lots of potted plants.

    Meanwhile, over in the "form follows function" areas, the guys sound like they are growling.
     
  8. DRG

    DRG Member

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    What you are saying is that men who do not like ugly recoil pads are faggots.

    I think a man who cannot withstand the recoil of a 7 mag without a gorilla-sized recoil pad is a wimp.
     
  9. Edd

    Edd Well-Known Member

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    What are some of the products you have designed?
     
  10. Clark

    Clark Well-Known Member

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    No, not exactly.
    My father derived the formula of a parabolic taper hydraulic cylinder for constant force over constant recoil distance, regardless of load. He did that in the 1950s when he designed the M55.

    I have not done any super important things like his patents, but I have figured out a couple things:
    1) The threshold of recoil pain in a rifle I have given some thought:

    Given:
    The rifle weighs 10 pounds.
    The bullet weighs 250 gr
    The powder weighs 75 gr.
    The muzzle velocity is 2500 fps
    The gas velocity = 1.5 projectile velocity
    The untrimmed large recoil pad is 9 sq inches
    The recoil pad stiffness is 100 pounds/ 0.2"
    The loss of Navcom material in Limbsaver recoil pad 75%
    The threshold of pain is ~10 kg/cm2

    Goal:
    Calculate if it will hurt.

    Calculation:
    projectile momentum = mv = [[250 gr] / gravity ]][2500 fps] = 250 gr / 7000 gr/lb / 32.2 ft/sec2 [ 2500 fps] = 2.77 slug ft/sec
    gas velocity = 1.5 projectile velocity = 1.5 2500 fps = 3750 fps
    gas momentum = 75 gr / gravity 3750 fps = 1.25 slug ft/sec
    Total forward momentum = bullet mv + gas mv = 2.77 + 1.25 = 4.02 slug ft /sec
    rifle momentum = bullet + gas momentum = 4.02 slug ft /sec
    rifle velocity = rifle momentum/ rifle mass = 4.02 / 10 pounds/ gravity = 4.02 / [10 / 32.2] = 12.9 fps
    Rifle energy = [1/2] [m] [v][ v] = [.5] [[10] / [gravity]] [12.9] [12.9] = .5 [10 /32.2] 12.9 12.9 = 26 foot pounds
    Energy not absorbed by recoil pad = rifle energy [1 - pad loss] = 26 fp [ 1 - 75%] = 6.5 foot pounds
    The recoil pad stiffness is 100 pounds/ 0.2" = 100 lb / 0.0166 ft = 783 lb /.13 ft =
    783 pounds compressed, 0 pounds relaxed, averages 391 pounds.
    [391 pounds] [.13 ft] = 6.5 foot pounds
    783 lb peak force / 9 sq in = 87 psi
    The threshold of pain is ~10 kg/cm2 = 142 psi
    87 psi peak pressure of recoil pad on skin / 142 psi threshold of pain = 62% of the threshold of pain

    Will it half hurt?
    No, because the whole shoulder moves, while 783 pounds of force may have been available to a brass statue shoulder, it was not realized. Only part of the energy goes into the recoil pad, unless the shooter is backed up against a tree.


    2) I am not saying that men interested in aesthetics with feminine voices are homos.

    I have observed that while speaking to people in the dark while walking the dog, I can make prediction:
    a) most masculine... male conservatives
    b) less masculine.... male liberals.
    c) even less masculine.... male homosexuals
    d) least possible masculine.... women's voices recorded and played back at half speed are an octave lower than original.
     
  11. DRG

    DRG Member

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    If you had spent your time in the gym instead of working out that math, you would have enough muscle tone to fire a rifle with a normal sized recoil pad.

    Please note this important information.
     
  12. DRG

    DRG Member

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    And what about recoil acceleration? I don't see it in those formulas. Your physics professor would be aghast.

    Empirical evidence shows that slow and long recoil (like a 15 pound 8 bore rifle) hurts less than fast, sharp recoil (30-378 wby). How does the rifle get going fast? ..... It accelerates.
     
  13. DRG

    DRG Member

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    Darth Vader had a deep voice and he was a leftist.
     
  14. Edd

    Edd Well-Known Member

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    Regardless of your voice tone, muscle mass, rifle recoil, or political views, those pictures depict shoddy workmanship.