lub...pc...hi-tec

Discussion in 'The Ammo & Reloading Forum' started by mudman35962, Feb 12, 2018 at 9:37 AM.

  1. mudman35962

    mudman35962 Member

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    just read for the third..forth.. time the explanation of bullet lub by Fryxell on the lacs site. i am starting to understand what he is saying. starting. with pc how does that work? same with hi-tec coating? they do not have anything wet getting wetter as the bullrt goes down the tube. so how does it stop leading?
    some one must have written about this. who? where can i find this info? i know it works, but why does it work. also there it the subject od BHN on these products, that is addressed by Fryxell. so meany questions. some one here must have found writings on the matter.
    there is enough stuff here to give anyone a headach.
    thanks.
     
    carver likes this.
  2. vassago

    vassago Well-Known Member

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    PC and hi-tec stop leading the same as jacketed or plated. There is no lead to barrel contact.

    Not the smoke nor the leading from lubed, what is not to like :)
     
    Big Mak and carver like this.

  3. mikld

    mikld Well-Known Member

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    Yep, the PC or Hi-Tek coatings aren't lube but protective coatings...
     
  4. mudman35962

    mudman35962 Member

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    if a casting is hard, how does the pc stop gas cutting? or does it?
    Fryxell explains in detail lub pumping, and bullet expanding to fill the bore. can hard cast with coatings expand to fill the bore? or are we expecting over size and coatings to do the same job? i am trying to grasp the physics [or what ever] of what is going on when you trip the trigger.
     
  5. vassago

    vassago Well-Known Member

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    Why would a non-hollow based bullet expand to seal the bore? FMJ doesn't and I'm pretty sure soft lead (flat base) bullets don't either, you size them slightly over-bore.

    PC does not really stop gas cutting, a gas check is still recommended where applicable.
     
  6. mikld

    mikld Well-Known Member

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    Most bullets, jacketed, plated and cast will obturate (swell). Jacketed will swell much less than lead but the pressure on the end of the bullet does bump them up (tens of thousands of pounds per sq. inch). Lead, even the hard alloys will expand to fill the rifling unless the powder charge is fairly low. Hollow based wadcutters were designed so as to expand even with extra low "target" loads...

    As I stated, PCing a lead bullet is the same principle as plating or jacketing, it's a protective coating the protects the lead from gas and friction...
     
    Big Mak likes this.