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Thread: 338 Lapua Bolthead at Midway

  1. #1
    Basic Member geargrinder's Avatar
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    338 Lapua Bolthead at Midway


    Midway is selling bare 338 Lapua Boltheads now.

    http://www.midwayusa.com/viewProduct...tNumber=927768

    I've been dreaming about a 338 Norma Mag in a centerfeed Savage. This might just be the ticket.
    "Muzzle velocity is a depreciating asset, not unlike a new car, but BC, like diamonds, is forever."-German A. Salazar

  2. #2
    defoxer
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    Re: 338 Lapua Bolthead at Midway

    What is the difference compared with the standard? Appear to be deeper, is that it? They should then be compatible with standard bolt/action?

  3. #3
    Basic Member geargrinder's Avatar
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    Re: 338 Lapua Bolthead at Midway

    If I'd seen it a few days ago I would have bought one. My last Midway order showed up yesterday.
    "Muzzle velocity is a depreciating asset, not unlike a new car, but BC, like diamonds, is forever."-German A. Salazar

  4. #4
    GLZ
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    Re: 338 Lapua Bolthead at Midway

    Quote Originally Posted by geargrinder
    If I'd seen it a few days ago I would have bought one. My last Midway order showed up yesterday.
    Better hurry, I just ordered 2. ;D I waited to long on the BA bolt handle, they are on back order. :'(

  5. #5
    bigngreen
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    Re: 338 Lapua Bolthead at Midway

    Thanks for posting that up!! I've got about half of the components for my 338 Norma Savage build, I'm thinking it should be awesome!!

  6. #6
    Goose
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    Re: 338 Lapua Bolthead at Midway

    This is great news, I've been dreaming of a 338 norma also. Can't wait. Sinman better get a reamer for the norma.

  7. #7
    nomosendero
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    Re: 338 Lapua Bolthead at Midway

    I have seen some 338 Norma info, I think on one of the Sniper Central or the hide, but tried to find it again & havn't yet.

    Any links that could be posted on the info will be greatly appreciated.

  8. #8
    sinman
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    Re: 338 Lapua Bolthead at Midway

    I'll get a 338 norma reamer if I can get a couple of people wanting one.

  9. #9
    Dano5001
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    Re: 338 Lapua Bolthead at Midway

    Ok, I am opening the can of worms ;D Is the norma safer than the lapua in a savage? is the lapua going to be safe with this bolthead? ;D

  10. #10
    Dano5001
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    Re: 338 Lapua Bolthead at Midway

    Did some searching, think I answered my lapua question.

  11. #11
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    Re: 338 Lapua Bolthead at Midway

    "Ok, I am opening the can of worms Is the norma safer than the lapua in a savage? is the lapua going to be safe with this bolthead?"

    My thoughts exactly. The 110 that Savage is making for the Lapua has thicker lug abutments in it as well as thicker locking lugs. I would question the amount of bolt thrust in a standard 110 action. :-\

  12. #12
    defoxer
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    Re: 338 Lapua Bolthead at Midway

    Dont forget Parker O's body of work.....thrust on the lugs is proportional to angle of the case walls and the amount of friction in the chamber.

  13. #13
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    Re: 338 Lapua Bolthead at Midway

    True but I wouldn't just trust that alone and bet my safety on the chamber having enough friction to hold the cartridge and keep it in place with questionable margins of safety for the lugs and abutments. Again I point you to what Sharp Shooter Supply said about Lapua size cartridges in the Savage action. He is a professional gunsmith with tons of experience with the Savage action and if he says it's marginal, I'm going to take his word for it.

  14. #14
    GLZ
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    Re: 338 Lapua Bolthead at Midway

    So the consensus is the RUM, WSM cases are the largest that can be safely handled by a Savage?

  15. #15
    Basic Member geargrinder's Avatar
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    Re: 338 Lapua Bolthead at Midway

    I think the only safe thing to say is that there is no consensus. :)

    I have my own opinion and don't listen to many others.

    If I choose to use one of these on one of my 110 actions I know I'm using them in a way they were not designed for or endorsed by the manufacturer.

    I accept responsibility for my actions. Pun partially intended. ;D

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

  16. #16
    sinman
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    Re: 338 Lapua Bolthead at Midway

    Some say its safe some don't, some have rifles with opened up bolt heads to lapua size and some don't.

  17. #17
    GLZ
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    Re: 338 Lapua Bolthead at Midway

    Quote Originally Posted by geargrinder
    I think the only safe thing to say is that there is no consensus. :)

    I have my own opinion and don't listen to many others.

    If I choose to use one of these on one of my 110 actions I know I'm using them in a way they were not designed for or endorsed by the manufacturer.

    I accept responsibility for my actions. Pun partially intended. ;D

    Geargrinder, I agree 100%. See above, I have 2 bolts coming. FYI, my calculatons (using 65,000 PSI for the RUM, WSM and 60,000 PSI for the Lapua as shown in QL and other internet sources) show the bolt thrust on the RUM, RSAUM, WSM, WSSM are for all pratical purposes the same as the Lapua! Less than 1.0% differance. This was calculated using actual case diameters. I am going to section some brass this weekend and try to get an actual I.D. for a closer look, I'm thinking the Lapua haas thicker walls.

  18. #18
    defoxer
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    Re: 338 Lapua Bolthead at Midway

    I'm interested to know how you have calculated the force on the lugs, this figure depends on many variables; how have you allowed for the frictional resistive forces within the chamber walls and have you considered the resultant force on the case (and the bolt/lugs) from the tapering of the chamber walls? this angle is different per round. If the force was calculated by multiplying the base area by the pressure; that would be erroneous...

  19. #19
    GLZ
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    Re: 338 Lapua Bolthead at Midway

    Quote Originally Posted by defoxer
    I'm interested to know how you have calculated the force on the lugs, this figure depends on many variable; how have you allowed for the frictional resistive forces withint he chamber walls and have you considered the resultant force on the case (and the bolt/lugs) from the tapering of the chamber walls? this angle is different per round. If the force was calculated by multiplying the base area by the pressure; that would be erroneous...
    You are correct, the actual number is much less than the number I came up with, but that is true with both cartridges. Most of the naysayers want to tell you that you cannot depend on the chamber to cartridge friction. So, if you compare apples to apples (NO Friction) the resulting numbers are so close it is scary. Due to the length of the cartridges (short bearing area) I suspect that the WSSM (super short) cartridges are the worst. If it really bothered me I would not have ordered 2 bolt heads or shoot my Rem Clone LAPUA. The bottom line is when you start modifying ANY firearm; YOU (the modifier) must take responsibility for your action and consequences. I'm good with that. If the next guy is not, DON’T DO IT!

  20. #20
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    Re: 338 Lapua Bolthead at Midway

    How can the thrust between the Lapua and a RUM be that close when the Lapua has a larger diameter head which results in greater surface area? The PSI might be close but with the Lapua it's over a larger area which is why there is greater thrust. I'm no expert but SSS has said before that it's too risky with a Lapua size cartridge in the Savage action and since he knows Savages inside and out and said that he tested it with poor results (lug setback), I'll heed his warnings. To each their own.

  21. #21
    GLZ
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    Re: 338 Lapua Bolthead at Midway

    Quote Originally Posted by efm77
    How can the thrust between the Lapua and a RUM be that close when the Lapua has a larger diameter head which results in greater surface area? The PSI might be close but with the Lapua it's over a larger area which is why there is greater thrust. I'm no expert but SSS has said before that it's too risky with a Lapua size cartridge in the Savage action and since he knows Savages inside and out and said that he tested it with poor results (lug setback), I'll heed his warnings. To each their own.
    Unless the CIP and SAAMI specs I have are wrong, which is possible, the Lapua is a lower pressure round.
    Please do not use or trust my calculations, but if I was scared of a Lapua I would run away form the RUM sized rounds also.

  22. #22
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    Re: 338 Lapua Bolthead at Midway

    I understand that the Lapua is lower pressure but you still have rearward thrust on a larger area because of the larger head so even though the pressure is lower I would think it would still push harder against the lugs. Same as with air brakes on a tractor/trailer vs fluid brakes on a car. The fluid brakes operate at a much higher pressure but the air brakes have greater stopping power because the air is pushing on a piston that is much larger in surface area creating more thrust against the brake pads. Take a look at what Fred at SSS said about it in this thread.

    http://savageshooters.com/SavageForu...c,36123.0.html

  23. #23
    defoxer
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    Re: 338 Lapua Bolthead at Midway

    According to CIP info;
    338Lapua Mag Pmax 4700Bar
    338RemUltMag Pmax 4400Bar

    The english tested the bolt force by lubricating the chamber, I understand this was a standard method, which converts all of the available energy to rear ward thrust (thus amplifying the actual thrust). It is only this method that produces the forces that you would calculate through pressure x area base. These forces would in no time set back the lugs and destroy bolts but not alter the outward force on the chamber (tending to stretch the case out)

  24. #24
    Nefarioud
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    Re: 338 Lapua Bolthead at Midway

    Quote Originally Posted by geargrinder
    I accept responsibility for my actions. Pun partially intended. ;D
    Nicely done sir

    Anyone Know what kinda of pressures the Edge is making? All this pressure stuff is dizzying. But I kinda occurs to me if your throwing the same projectile at very near the same rate igniting similar loads of the same powders with the same primers; the forces ought be near the same. Still, by my ciphering the 338LM puts about about 1132 more pounds of force on the bolt head than the higher pressure loads with a smaller bolt face at stated pressures. (though BAR works, more people readily understand pounds, even the "english" still use pounds but it's mainly to buy stuff) It also occurs to me that even the 15,580 that the LM is capable of exerting would fall below the couple compressive stress tolerances I've seen for the steels in question.

    Will it eventually ruin the action? Probably-ish. Would that stop me from building a crazy barrel burning hot-rod? Probably not-ish. Will we ever really know unless someone does it? NO. Do we really need to know? No Idea

    Experimentation is not without it's risks. Unfortunately, innovation on any particular scale requires experimentation.

    Whether or not it's worth the risk is an individual decision. I bought a 110BA because the money was worth less than the risk, I'll use that action as the basis for my hot rod in the spring; but, that's just me

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