Spider for pistol barrel work

[gzig5]

I am in need of a spider to do some muzzle threading and perhaps some chambering on a couple of pistol barrels. If I could use it to a basic true up on Remington and Mauser actions, so much the better. First up is a Ruger MK2 5.5". I'm working on a EMCO Super 11 lathe with a D1-4 spindle and have an 8" four jaw to hold the spider, or if it is worth the trouble, I could modify a faceplate or dog driver to bolt it to. I'm struggle with how big it needs to be. Barrels would be 7" long max and about 0.9"-1" diameter max. I was thinking 3.5" diameter, with ~1.5" hole, using 1/2-20 tipped screws, but how long and what screw spacing would you all recommend? Commercial ones seem to be about 8" long with 3 or 4 sets of screws but that seems excessive and I don't' think I'd need to use that length. Seems to be a good way to put a bend in an action if you aren't careful.

 

[linebaugh]

The one I made is 4" spacing and I had a third set in the middle that I threw away. I would guess my OAL is 6" and I cus a brass taper that somewhat llcks into the spindle. If I built another one I would move the outdound side as close to the edge as reasonable. I would guess mine is about an inch in.
Set the outside spiders pivot point up over the neck/throat area like you would on a regular chamber in the 4 jaw.

I dont like using it but no choice on short or pistol barrels. I make light cuts when using it but its plenty rigid.

 

[Doug Beach]

Put the screws in at the spacing you can immediately foresee a need for. It’s an easy thing to add more holes later. I’ve got a spider that has grown at least two additional sets of holes.

 

[LVLAaron]

For a light pistol barrel just doing threads, something like this would work, probably.



If you're a through the headstock guy... make an extension



If you really hate yourself.. make a chuck!

 

[LVLAaron]

Here's a drawing of a more typical jig like viper and gretan sell.

My two cents, and I'm just a dude who tinkers, figure out how to make the extension work. These jigs work, but they're a hassle and can move on you pretty easily.

 

[Will Henry]

As it happens, I was just setting back an old BR barrel which was just a little too short to reach through the headstock. So, I decided to put the barrel into the old action truing fixture, which I made sometime in the mid-eighties when I had to true a Winchester. Anyway, I've recorded the process and will upload it once I finish some truck work had to be done.
My scruffy old fixture is not nearly as attractive as those Aaron shows. He seems to go out of his way to make me feel inadequate! His point about jigs being a bit of a hassle is true enough. I agree with the idea of using an extension to allow working in the headstock. WH

 

[gzig5]

Here's a drawing of a more typical jig like viper and gretan sell.

My two cents, and I'm just a dude who tinkers, figure out how to make the extension work. These jigs work, but they're a hassle and can move on you pretty easily.

Thanks for the pics and info. I'm definitely trying to avoid making a big chuck, but I tend to overthink/over-do things.

So if I understand you correctly, you'd rather screw the barrel into an extension that would reach through the headstock and use spiders at either end as normal on a rifle barrel muzzle threading op? How would you do the chamber end of a short barrel? Not sure I understand the thinking behind that being stronger because you still only have the spider screw contact in either case. Maybe I'm missing the point? I use a spider rather than four jaw because I find the finer 20tpi thread much easier to zero the runout. I always take light cuts when threading/chambering through the headstock with spiders on either end, and haven't had anything move so far as I know.

 

[LVLAaron]

No picture handy... but take that same "extension" and make a clamp so you can hold onto the muzzle end of your barrel.

What I'm saying about the jig I posted the drawing for... they can move (in my experience) it's easy to get a couple tenths of movement from heavy cutting or bumping it, etc. You can make it work it's just kinda tedious.