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    • #25398
      Goodsteel
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      Custom rifles require custom headspace gauges. Ordinarily, this is something that you have made by one of the custom tool houses like PTG (I highly recommend), but there are times, when making things fit just right in a true custom wildcat requires something that can be quickly modified to perfection, then sent off for hardening if it ends up being something you want to hold onto for a long time (actually, hardening is optional as it would take many many builds to wear out a gauge made of unhardened tool steel).

      Tonight I found myself in just such a situation as I am building an improved 35XCB for bjornb. The object is to make the brass fit the chamber absolutely perfect, and in classic XCB style, it needs to be easily converted from standard 30-06 brass without breaking too much of a sweat.
      In order to do this, I took every brand of 30-06 brass in the shop, and ran them through the 35 Whelen FL sizer, then I trimmed the necks square, then measured the length.
      What I found was that they all came in .032-.040 short.
      I trimmed the bottom of the die off to allow for this, effectively pushing the shoulder back and making the necks longer, and going an extra .040 because I designed the 35XCB to have an extra long neck (to the detriment of case capacity I know, but I never heard anybody complain about not being able to get enough powder in the 35 Whelen to push as fast as they wanted to, so I figured it was a mute point.)
      By pushing the shoulder back, not only did I make the neck longer, but I extended the overall case length as well so the finished brass measured 2.460 (Whelen spec is 2.494)

      So after all this plussin and minusin, I found I need a 30-06 headspace gauge that is .080 shorter than the standard. Now I could call up PTG and tell them to make it happen, and 4 months later I get my gauge, but this project is behind enough already, and this is by nature a wildcat, so we have a situation here that is perfect for a custom headspace gauge.

      I documented my work, so I could post it here for your education and reading pleasure, so without further ado, here we go…………

      The first thing to do is select a good piece of tool steel. I had a piece of 3/4″ handy, so I used it.
      Turn it down to the rim diameter of the headspace gauge.

      Next, press the nose of a similar gauge up against the compound slide and sight down the side of it in comparison to the ways of the lathe in order to set the angle for the nose of the gauge. This technique takes practice, but a skilled lathe operator can align his compound within seconds of the angle using this method. It’s no different than shooting a small group with iron sights. You learn to hit what you’re shooting at.

      Now I turn the nose on the gauge, and drill the center in the nose (this is extremely important if you send it off to be hardened and need to grind it later).

      Next, I turn back the shank so it will fit in the chamber.

      Looks about right.

      Now I saw it off and flip it around:

      Turn it flat, and drill the center. Remember, this is the other end that you will use to hold the reamer when grinding if changes are to be made later after hardening, also, this one is very important, simply because it makes it so that if you accidentally dry fire the rifle on the gauge, your firing pin will not be broken. Do not neglect this under any circumstances:

      Now, the Hornady headspace gauge is used to measure the 30-06 GO gauge. This number is recorded, and then the caliper is zeroed.

      Then the new gauge length is measured against the previous one. Looks like I have .090 to go before I have a 30-06 GO gauge:

      The gauge is put back in the lathe and the tool is touched off carefully, then a dial indicator is used on the ways to measure exactly how much is being removed. Once the excess material is removed from the back of the gauge, the center hole is drilled deeper.

      Once the correct length is achieved, the extractor cut is made, and the corner of the gauge is broken on a 45 degree angle.
      Things are starting to look a little more like what we are after:

      The paint groove is added:

      Final size is checked again, the caliper is zeroed on the standard and the gauge is checked again. Back and forth till I am satisfied what I am seeing is correct.

      Finally, paint is added to the paint ring ( I use grey to distinguish my custom gauges as a wildcat standard). Here are three gauges, one custom and two made by PTG. From left to right: 30-06, the 35XCB Long, and the 30XCB. The one on the left and right are made by PTG, and the one in the middle is what you just saw me create.

    • #25407
      Wright Arms
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      I don’t know if anyone else is watching, but I am. Nice technique to have in one’s ‘bag ‘o tricks’. Thanks for sharing.

    • #25449
      timspawn
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      Pretty darn amazing if you ask me. I wish I had the talent.

    • #25471
      dverna
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      Those hands and fingers are too clean to belong to a machinist. LOL

    • #25479
      Goodsteel
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      dverna;n3843 wrote: Those hands and fingers are too clean to belong to a machinist. LOL

      That’s not the first time I’ve heard that.
      Not many machinists can fabricate precision gauges on 50 year old lathes either.

      “Yes I’m a gunsmith. No I won’t help you fix your Chevy.”

      Say you asked me to build you a custom rifle with 10 coats of finish rubbed into the wood by hand and a few pearl inlays just for flare. Oh and make it shoot one hole at 100 yards too while your at it. How much dirt grit and grime do you want included in the finish of your rifle free of charge? LOL!

    • #25486
      lar45
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      Excellent work. Next make your own reamers? Probably not worth the time involved.
      So is the 35XCB Long going to be a cast boolit hunting gun? Sounds interesting 🙂

    • #25492
      Goodsteel
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      lar45;n3858 wrote: Excellent work. Next make your own reamers? Probably not worth the time involved.
      So is the 35XCB Long going to be a cast boolit hunting gun? Sounds interesting 🙂

      I could make my own reamers. Just like I can make my own molds. I don’t though. There are specialists that have taken that to a level that is very lofty indeed, and I’m grateful to pay them to do what they do, so I can focus more on what I do.
      I’ve never seen a better example of “win win”.

    • #25512
      Anonymous
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      I have made a few molds, but haven’t tried to make a reamer. Clymer and PTG can take care of that. Can I ask what brand your lathe is?

    • #25519
      Goodsteel
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      chipmaker;n3890 wrote: I have made a few molds, but haven’t tried to make a reamer. Clymer and PTG can take care of that. Can I ask what brand your lathe is?

      LeBlond Regal 17X120.

    • #25534
      Anonymous
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      Good machine, thank you.

    • #25592
      uber7mm
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      Great write up. Thanks for documenting the process.

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