flute my own barrel

Discussion in 'Gunsmithing' started by dogone, Jan 4, 2014.

  1. dogone

    dogone Member

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    I have a mill in my farm shop and have a few skills. Can I, or should I flute my own barrel? Maybe they have to be done before rifling or chambering. Any thoughts on the project?
     
  2. SidecarFlip

    SidecarFlip Well-Known Member

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    As a professional tool and die maker and shop owner, I'd say you are in over your head. A'Farm shop milling machine and a few skills' won't cut the mustard and you'll screw up your barrel, but it's yours and a new one can be bought and taken to a competent machinist/gunsmith and done properly.

    There is a whole lot more to fluting a barrel blank that jut a ball mill and milling machine.

    It distills down to 'pay me now ot later' scenario.

    Put another way, I have a 'few skills' as well and I wouldn't attempt fluting a barrel because I don't have the proper machinery to do it, not do I have the correct fixturing.
     
  3. Trickymissfit

    Trickymissfit Well-Known Member

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    I worked with a guy that brought in a Remington heavy barrel in the shop and fluted it with an old Barber Coleman hob!! He used a standard gear cutter, and the flutes were pretty, but the slight taper created a headache he never quit overcame. Took him about an hour after he got everything setup with a very light cutting load. Called me down to show it to me while it was still chucked up in the hob. Then he removed it, and found out that he'd made a serious mess of things! The barrel must have bent a quarter inch! I actually straitened it to within about .005". He then took a very fine pencil torch and got it within a thousandth. Barrel went from shooting half inch groups to two inch groups in a .308! And that was after a complete recrown and a heavy bead blasting. Four hundred dollars later he was back to shooting in the half inch range again, but he did own a good tomato stake.
    gary
     
  4. Hired Gun

    Hired Gun Well-Known Member

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    All barrels are fluted last thing before they ship so there should be no problem doing it. Now why I won't do it.

    When I got started I was full of piss and vinegar and figured I would be able to do everything. In my previous job I cut splines and large key ways on shafts fairly frequently so figured fluting would be no problem. I bought a top of the line rotary indexer and the heaviest tail stock for the mill I could get. I had all sorts of super sturdy fixtures and was ready to go. I then visited a barrel manufacturer and during our tour, barrels were going in the garbage from every station at an alarming rate. The owner said they wreck/cull/reject/QC fail tons of barrels every month. It's just part of the business. I saw the full dumpsters.

    After watching the pros wrecking all those barrels I decided it was way too big of risk for me. If they wreck one, they just grab another and carry on. If I wreck one it's 300 some bucks and another lengthy wait. I would either order it that way or send it to a specialist and let them assume the risk.
     
  5. SidecarFlip

    SidecarFlip Well-Known Member

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    My only correction to your post is.....

    It's not a dumpster (and thats a trade name for the Dempster Corporation's trash hopper BTW), it's a roll-off box/container. Garbage goes in a 'dumpster', scrap goes in a roll-off box.

    Barrells (quality ones that is) don't come cheap folr that reason. The rejected rate is very high and so the cost per unit is high as well.
     
  6. SidecarFlip

    SidecarFlip Well-Known Member

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    Reminds me of the AK47 I had that 'shot around corners'. The barrel wasn't fluted but was curved or so it seemed.

    Some machining operations are best left to professionals and this is one.
     
  7. lazylabs

    lazylabs Well-Known Member

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    I would not say that ALL barrels are fluted as the last operation. the cut makers can flute them before rifling.
     
  8. SidecarFlip

    SidecarFlip Well-Known Member

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    What the hell is a 'cut maker'. I believe you mean before the machinist finishes the barrel blank.

    Gary and I would take offense to your generic slang, but then, the generic term for any machining seems to be 'milling'.

    I digress.:)
     
  9. lazylabs

    lazylabs Well-Known Member

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    FLIP....

    CUT rifling is a method of cutting the grooves one pass at a time. If you take .0001 cut and then index through the number of gooves you have, advance the cutter and repeat until the desired goove depth is reached. If you search google you can find more information on the process.
     
  10. SidecarFlip

    SidecarFlip Well-Known Member

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    Rifling is one thing. Milling flutes is another, entirely. None of which I want to or plan on doing now, or in the future. Not in the firearm business (other that tinkering with my own and close friends).

    I'm a nonenclature person, probably because in machine shop discipline, nomenclature is everything.

    When I have an employee describe an operation to me, I want them to use proper terminology. Makes it easier to understand, streamlines the conversation and tells me they actually have a grasp on whats occuring so we can make a rational judgment or fix the issue..

    On here I'm just a poster. In my shop, I'm the boss and we do things according to Hoyle.:)

    Call it whatever you want. I don't ascribe to goggle terminology concerning machining operations or machining discipline. That comes with experience and qualifications earned in the field. I have one of those cards in my wallet and a diploma on the wall that states I'm a qualified tool and die maker and I've satisified the requirements set forth to attain that.

    My comment wasn't meant to be dispariging, it was meant to be constructive, because, like Gary, I know what I'm doing and I know what I cannot do correctly. Fluting any barrel is one of those operations. My shop is not equipped with the proper fixturing. I may have the machine tools at hand but no impetus to bugger up a tube.
     
  11. I was under the impression that all barrel fluting was done on a HORIZONTAL mill with a proper fluting cutter after witnessing it done. I had always pondered doing it on my vertical mill with a ball end mill. glad I never attempted it after witnessing it done by a professional. I don like the looks of a fluted barrel and I do HATE having to index them during install. its worth the $120 to have it done right by someone like twistedbarrel. I think you would be ahead of the game to have the chosen manufacturer do it though just in case there was an issue. I doubt any of them would offer much help if you had a barrel that wouldn't shoot if someone else fluted it!
     
  12. MTBULLET

    MTBULLET Well-Known Member

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    got some old barrels, set 'em up and try it. If you can mill a key slot, you can mill "flutes". (it ain't rocket science) practice and patience.
     
  13. shortgrass

    shortgrass Well-Known Member

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    Forget the ball end mill idea if you're using a vertical mill, use a shank mounted cutter and work from the side, instead (looks like a woodruff key cutter only has a radiused cutting edge. go to MSCs's web site and search "concave, convex cutters). The cutter costs more than a ball end mill, but will work a lot better (has more cutting edges). Plus, I think the set-up is simpler to make. Calculate cutter speed (RPM) and feed rate. Make shallow cuts. Flood coolant is required. You will, no doubt, want an even number of flutes. Cut the first , index the barrel 180 deg and cut the second. After the second flute, index 180 deg plus the amount required for the one you will cut that's next to the first flute you cut. Progress around the barrel in this fashion until you have all the flutes cut. What you do to the outside of a barrel, be it fluting or contouring, may effect the inside of the barrel. I see no reason to "practice" on old barrels as the mechanics of indexing and setting stops for "where to start" and "where to stop" are basic to understand. Fluting 'old' barrels will tell you nothing about whether you are effecting accuracy or not. 'Git after it!'
     
  14. yorker

    yorker Well-Known Member

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    I was doing some reading earlier and it seems that most fluting is done before the bore is cut to help minimize stress....