Indicating a short barrel in a lathe

[Kck]

What's everyone using to add length to a short barrel to give enough length to get to the jacking bolts on the outboard spider? I have an extension that I made sometime back that works well for custom barrels but I tend to run out of room at times when doing cut, crown and thread jobs on half-@$$ed factory barrels that require a lot of pushing and shoving to get the bore indicated.

 

[GenePoole]

I use a cat's head: kinda like a stacked spider. Originally built it for action truing and pistol barrels, but it works great for short rifle barrels as well.

 

[tobnpr]

^^^
This.
Bob Pastor (Viper) has a commercial one, used for both short barrels and indicating receivers.

 

[Tucker65]

If you're working on the muzzle end couldn't you just make a threaded tube and screw it on the receiver threads to extend the barrel far enough to reach your outboard spider.

 

[linebaugh]

Just did one this week in a homemade cats head. Also use the same for some action modifications.

 

[Kck]

I think the cat’s head type fixture is gonna be the ticket, thanks gents.

Tucker65, that’s actually what I use now but sometimes the factory barrels need more room than I have in my spider to get the muzzle dialed in. I think the cats head fixture will allow for more adjustment.

 

[ridgeway]

Drive with spindle(4 jaw, adjustable 3 jaw, collet, etc) and hold in steady.

 

[Tucker65]

My lathe is pretty long and even a 30" barrel wouldn't stick out the back end of the headstock. The spindle bore runs really true so I turn sleeves that press on the barrel and slide into the spindle bore when chambering. I indicate at the throat and just let the muzzle end run true on my turned sleeve in the spindle bore.

I made this attachment to bolt onto my steady rest for threading for muzzle brakes and crowning with the action still attacked to the barrel. I've tried it a few times and it seems to work pretty well. You can also spin the lathe as fast as you want without having to worry about the steady rest seizing up on the barrel or marking it up.

 

[Keith Kilby]

I use a system similar to Tucker65 with sleeves inside the spindle but my sleeves are reamed out and I use a center rod with 60 angle on end that slides through the sleeves. Sleeves have set screws and I can adjust the center in/out between the two sleeves. I hold outboard sleeve with 4 screws in a "cathead". I can use this system on either end of a barrel. I also use threaded extensions that I made for either breech or muzzle end. We all cut off an inch or so at muzzle...I'll thread a sacrificial end between centers at the muzzle for my extension. Threaded part goes away when barrel is cut and crowned to length.

 

[Dave@MAM]

I have a long extension threaded to screw into a Rem thread and several others. I have another that is bored on one end for AR sized barrel extension and the other end for 10-22. I epoxy the barrels in, put them through the spider and dial in as normal. When finished, heat it up a tad and pull em out of fixture and move on.

 

[Dave@MAM]

This is another variation of an above post, that is very handy.

 

[tac284]

My lathe is pretty long and even a 30" barrel wouldn't stick out the back end of the headstock. The spindle bore runs really true so I turn sleeves that press on the barrel and slide into the spindle bore when chambering. I indicate at the throat and just let the muzzle end run true on my turned sleeve in the spindle bore.

I made this attachment to bolt onto my steady rest for threading for muzzle brakes and crowning with the action still attacked to the barrel. I've tried it a few times and it seems to work pretty well. You can also spin the lathe as fast as you want without having to worry about the steady rest seizing up on the barrel or marking it up.


View attachment 1210170

I spy a Mori Seiki/Webb/Hwacheon.... very nice!

 

[Roeder]

Some ingenious solutions here. What I have done in a pinch is to make a sleeve out of Delrin, long enough to bridge the gap Either bore a taper to match the last inch or so of the barrel at the muzzle or just bore a slight step so that the sleeve engages 2 places. Tap it on so it's tight. This works well if the barrel is just a little too short to engage the outboard spider. I can easily reach in with a long stem indicator to indicate the bore at the muzzle.