Chucking shorter barrels

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I do a lot of airgun and some limited rimfire work and frequently use barrels too short to go thru my headstock, even with the rear spindle tube drilled and tapped as a spider. I have considered trying to make some sort of thin chuck to gain a couple inches at the headstock. What are folks doing on chambering barrels in the 14" - 19" range?

I spent about 50 hours with a long homemade boring bar truing up the spindle tube then honing it. I currently use one of two centering methods. One is to turn targets on the barrel concentric to the bore and make a custom fit puck to slide into the spindle tube to hold the barrel. I also have a precision fit rod with interchangable centers to slide into the spindle tube. Both methods allow no way to indicate or verify the muzzle position inside the tube and of course these parts have to have some clearance to operate. My lathe is a Jet 14x40 about 10 years old. Thanks, Will Piatt
 
The few I've done I've done using the steady rest. I dogged one on a drive plate and chucked one in the 4 jaw. I guess I can't find the downside of the 4-jaw and steady method. I would do it again.

al
 
I use an action blueprinting fixture/cathead. I set it up using the wider spacing on the bolts for long actions. Got this tip from Rustystud.
 
Will, that is how I do all of my barrels, since my Pratt & Whitney Tool Room Lathe is way to long to do any barrel with a spider. I personally think it is a great way to chamber.

Gary Walters did a complete write up, with pictures, of my chambering method. Just search for Gary Walters, Jackie Chambering.........jackie
 
I guess I can't make the search function work for me. Anyone find this thread? I remember looking at it a while ago. Link???
 
Shortbarrellongheadstock-vi.jpg
 
I use a similar fixture as the sketch above, except I use a 3/8 inch brass mandrel for what ever barrel I am using. I do a lot of muzzle threading for 10/22 barrels that are 16 inches long.

I took a round aluminum bar I got from the scrap yard and mounted in my steady rest and indicated it as close to true as I could. I then drilled a hole about 3 inches deep, and trued it with a 3/8 inch reamer. Then center drilled the hole for a live center, mounted it between centers.

I worked the aluminum bar deep inside my spindle taking off about a thousandth at a time until I got the depth I wanted. I pushed and twist the bar, making black marks on the high spots on the aluminum. Then I would remount the bar between centers and skim off the high spot. The brass mandrel I use is such a tight fit in the aluminum that I had to drill a relief hole so the air could escape at the bottom of the hole. Once I shove the brass mandrel into the aluminum rod, it stays put, with no play.

I use another brass mandrel to temporarily hold the muzzle in place with the tailstock while I get shims in place to indicate the bore. The bore runs true from the muzzle to the end of a pin gage.
10-22SetUp.jpg
 
jackie schmidt said:
Will, that is how I do all of my barrels, since my Pratt & Whitney Tool Room Lathe is way to long to do any barrel with a spider. I personally think it is a great way to chamber.

Gary Walters did a complete write up, with pictures, of my chambering method. Just search for Gary Walters, Jackie Chambering.........jackie
Click to expand...

I just went through this link and it is the one I remember from before. Where is the blueprinting fixture/cathead. Looks to me like you are chucking the barrel straight in the 3-jaw set-tru chuck??? Where is the end of the barrel opposite of where you are working? floating around someone inside that cavernous spindle??
 
call me dense, but I I see a barrel chucked in a 3-jaw. I see some type of jig or something in photo 12 but it is in the same 3-jaw. Do you slide the muzzle into this and then slide this into the spindle? How would you ever make any adjustments to the muzzle end when indicating the breech? I can see it with the the large jig used to true actions. I guess if you clamp this in your 4 jaw tight enough, it will hold and not move around on you. I guess this is the best route to go then.
 
Ron-that is almost exactly what I did. My Asian lathe had a rough spindle bore so I made a long 1" diameter boring bar and spent a week boring it out true with the machine and then honing the bore until my aluminum rod would just barely slide in consistent all the way. It is a air tight too. I guess my problem is I have no way to double check the "blind" end. I have had good results though. Will
 
Gentlemen, look at the pictures, then read my commentary. I don't know how I cold possibly explain better what I am doing..........jackie
 
I guess I am making some assumptions here that I shouldn't have. I thought there were basically two schools of thought on this through-the-headstock-stuff:

The Gordy Gritters method [ or whomever he borrowed it from] and the

method where you use your spider on the end of the spindle to indicate the bore on that end as well as indicating on chamber end.

If I am understanding this right- from reading through the whole thread- not just the commentary post, both ends of the barrel are turned down (somehow) so that a semi-circular ring is pressed on that can flux in the 3-jaw. In addition to this semi-circular ring, there is an additional "alignment ring" which is a press fit to the inside of the spindle which has either been bored true or Pratt&Whitney did it before it was shipped. No effort is made to do any indicating to the end in the spindle other than what was done when the small tenons were turned to press the ring onto???

Couple of thoughts/questions- do you reuse the rings, all four? of them each time or do you have to make new ones for each barrel? If you reuse them, it seems they would only work for a similar barrel contour and not very friendly to doing different contours such and HG, LG, Palma, Varmint or what have you?

The alignment ring noted in photo #12 looks to be flat for some distance around the entire circumference. Won't this put the barrel in a bind when you dial in the chamber end with the Buck chuck?

Also, wouldn't the commentary for photo #1 better read "#1 Indicating muzzle, chamber end is supported in spindle bore by alignment ring"

What seems plain and obvious to you, apparently isn't to some of us based on my study of it and some of the other posters in the original thread.

Dennis
 
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Do you guys think something along the lines of this would work for chambering a short barrel through the headstock? Maybe a piece of 1.25" aluminum or brass 6 to 8 inch's long taper bored so a muzzle could slide in a few inch's with brass tipped set screws holding it secure? Then indicate off it at the spider end. Just a thought.
 

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Dennise, I just looked at all the pictures again, and the commentary, and I am sorry if you can't understand it.

I honestly do not know how I can explain it any better........jackie
 
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I'm chambering my short-ish rimfire barrels through the headstock on my Haas TL-1. What I do is basically use a bloop tube on the muzzle end of the barrel and clamp my spider on it. Normal through-the-headstock chambering and threading after that. When I do the crown, I tighten my spider on the action that is now installed on the barrel. I do through the headstock chambering and crowning so I can align the bore as per the Gordy Gritters chambering video from Grizzly.

Eric U
 
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