Sunday, August 19, 2012

Well, there's your problem...

So I'm loitering back in gunsmithing the other day when one of the sales crew brings a customer's rifle back. Seems the customer got a laser boresighter stuck in the chamber.

The rifle in question is a crudely-sporterized 1916-dated Mauser 98, still with the stepped military barrel and a pre-WWII-looking European sporter stock, with something halfway between a Schnabel forend and a tumor, cross-hatching in the wood to approximate checkering, and a wrist so thin that it's a wonder it didn't blow into splinters when the trigger was pulled.

Gunsmith Bob heaved and tugged on the bolt handle, but it wouldn't budge, and so out came the plastic hammer. A couple good whacks and the bolt flew open, sending a little shiny brass fingernail shaving of  the boresighter's cartridge rim flying through the air.

Next was an oak dowel down the bore, but the Mauser is known for its rather vigorous camming action on closing, and that boresighter was wedged in but good. The dowel splintered impressively enough to hit me in the neck with shrapnel.

Finally, repeated blows to a fiberglass shotgun rod managed to dislodge the thing.

What do you think fell out?

That's right, Cletus had a .243 boresighter in his 8x57mm chamber. It was burnished real shiny around the shoulder, too, where he'd grunted and strained in closing the bolt.

Here's the kicker: The rifle did not have pre-war Euro claw-type scope mounts on it, nor either was it drilled and tapped for regular mounts. The sight on the gun consisted of a blade up front and a fixed sheet-metal aperture silver-soldered to the receiver bridge. So what in the name of Paul Mauser was he boresighting in the first place?

32 comments:

  1. He was bore sighting because that's what Remus said he should do.....

    Steve

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  2. Because he could....

    Number one law explaining humanity's high's and low's.

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  3. Mandatory gun owner licensing and training would have prevented that.

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  4. We gunsmiths love people like that. They are our bread and butter. My favorites are the ones with .22's that were last cleaned when they left the factory.

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  5. Force fitting a boresighter that is 12 to 15 thousandths larger than the chamber at the boresighter's neck is not too smart.

    But it takes a genius of sorts to make an aperture sight, carefully file it to fit the receivers bridge and to zero at X distance so it will be zero at Y distance!

    If that's what he actually did he has more patience than I have.

    Stranger

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  6. Stranger,

    The rear sight predated the invention of the laser by several decades. ;)

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  7. If somebody's going to go to the trouble of aperture-sighting a Mauser 98, as I would if I were doing a custom build, why then would they not use Lyman's #48 with the proper drill/tap? It'd be a lot less trouble. And you don't boresight that... you shoot to zero at 25yds and fine tune to the farthest distance that won't cause midrange misses as per Jack O'Connor ("The Hunting Rifle", 1970).

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  8. mustanger,

    The aperture sight was done back in the late '20s or early '30s (or perhaps the late '40s,) by whatever German village gunsmith sporterized the rifle.

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  9. Tam, that probably makes a huge difference. We, or at least I, don't know of German gunsmiths being able to get/use American-made Lyman sights between world wars.

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  10. "I seen one a'them REAL shooters do this boresight laser thing. I'm onna do it!"

    MC

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  11. Tango Juliet:

    It wouldn't help. How long has there been mandatory training and licensing of automobile drivers?

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  12. Um, forgive my ignorance, but doesn't the bolt of a Mauser come out? If that is the case and one desired (for some strange reason) to check the sight alignment more closely than can be done by sighting down the top of the barrel, could one not simply improvise a mount and boresight the gun by, ahem, sighting down the bore?

    ...I realize the Jedi in question would have had to come up with some way of securing the rifle at the proper height without blocking his ability to line up his noggin with the sights, but 2x4s, shop rags and duct tape are well-nigh universally available....

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  13. This is why I'll probably never get up the nerve to learn to the point of being a paid smith.

    Later on when Cletus blows up his gun and likely damages himself the he or the next of kin in his clan will sue the smith that last touched it.

    For it certainly couldn't be Cletus' fault. That smith musta done something.

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  14. "Windage and elevation, Mrs. Langdon. Windage and elevation."

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  15. I think it's a cute story.

    The little feller was workin' on making his gun better.

    --wait, he was about 8 years old or so, right?

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  16. Roberta:

    Yep. That's how you are supposed to bore sight, if you don't have a crap load of gadgets.

    Pull the bolt, prop the rifle up and secure it pointing at the grass 25 yards away is something bright, like a hubcap, look down the bore, and make sure said hubcap is centered in the bore.

    See if the sights actually point at the hubcap. Adjust them until they do.

    Then you can actually sight Mr. Rifle in with real ammo.


    This ain't rocket science, and you don't have to jam crap in the bore.

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  17. But that feller down at the gun show tole me I could get grandpappy's ole rifle shootin right good with one of dem lazer gizmos...

    I don't support manditory gun regulations or training, but I do think one should have a licence to own a Dremel.

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  18. It never ceases to amaze me, the many ways that folks can screw up their cars, motorcycles, firearms, etc. It bring to mind that they are lucky that reproduction is mostly out of their control. And no, don't go there either.

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  19. Tam, may want to give GS Bob a call. A .243 boresighter should have rattled around in that 8x57 chamber. Unless that boresighter laser was for a .270. If that rifle was re-chambered for something else, Cletus may have a surprise in store when he pulls the trigger...

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  20. Al T.,

    8x57 has a diameter at the shoulder of 10.95mm. .243 has a shoulder diameter of 11.53mm.

    Bob, Shannon, and I all laid eyeballs on it; give us a bit of credit. ;)

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  21. (While 8 Mauser and .308 have very similar base diameters, within a thousandth of an inch, the Mauser case has a more pronounced taper while the .308 is much more straight-walled.)

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  22. Back when I was working as a machinist, I would have considered 23 thousandths of an inch (.58mm) a pretty big difference in diameters. I'm surprised he could get that bolt closed at all.

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  23. never underestimate the sagacity and stick-to-itveness of the common southern redneck. this is much the same mind set as birthed NASCAR.

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  24. At the range where I work part-time as an instructor, this guy came in the other day with a Glock 30. "I think I put it together wrong," he said. Indeed. The recoil spring assembly was crammed tightly into the barrel.

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  25. Perhaps he was planning to go somewhere to cull feral hogs, and decided he needed to boar-sight his rifle....

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  26. Gun newbie here.

    The laser bore sight thingy pokes into the distal/muzzle end of the barrel, yes? They make ones that go in like a real cartridge?? So much to learn...

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  27. Ah, got it. Taper... Looked at the drawing in the Barnes Reloading manual which covered various lengths and diameters, but not tapirs or any other kinds of swine....

    Al

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  28. That's just excellent... I suspect this will be the funniest thing I hear all week.

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  29. Can't we celebrate diversity a little? A stupid guy with a stupid rifle doing stupid things. You rather he have a hold of a 380 Savage autoloader or a Swiss K31? I'd steer him toward ammo pile and tell him he had a rifle that would really shoot good!

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  30. Even with the shorter length to the shoulder of the .243, it looks like he would have had to swage that boresighter down by about .006" to get that bolt closed. I'm sure the boresighter is not made as soft and thin as a cartridge case. Let's hope he doesn't try to fire a .243 or a .308 in that rifle. He could probably get the bolt closed, but it would be a bad idea.

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  31. Make that .015", not .006". I'm still impressed that he could get that bolt closed.

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  32. Wha'cha wanna' bet Cletus has a real good four pound hammer and a piece of a live oak branch? And had cuzzin Melvin line the oak branch with the bolt handle while he hit at it.

    Gerry N.

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