Muzzle threading on short barrels

[DaveTooley]

Or slip a mandrel into the receiver and drive it that way while running the barrel in the steady. WH

Yep cap screw into the mandrel in the bolt notch.

 

[DaveTooley]

Steady rest always ruins the finish on the barrel especially a blued one.

I'm not in the shop to take pictures but I'll describe what I do. I have a series of metal sleeves, Aluminum and steel, that fit over the barrel. The trick is to wrap the barrel with a triangular piece of paper, offering a taper for the bushing to slide over. Twist on the bushing, tap with a mallet to snug it up, turn true between centers. Run the trued sleeve in the steady rest. Do the work and tap off. No marring.

 

[WSnyder]

Or slip a mandrel into the receiver and drive it that way while running the barrel in the steady. WH

That's what I said I do And yes as Tooley said a capscrew to drive it. Easy peasy

 

[WSnyder]

Steady rest always ruins the finish on the barrel especially a blued one.

There's ways around that. I've done it many times.

You can sleeve it as Dave does or you can do it with a center in the bore. Run a piloted center reamer in to establish a good 60˚ center. I use a small tip low profile CNC live center. Once you cut and thread the tenon (leave it a touch long) you switch over to the steady directly on the threads and then finish the crown and tenon to length. Lots of ways to do it.

 

[Walt Krafft]

The outside of the muzzle is rarely concentric to the bore so a steady rest can have concentricity issues. I have a set of false centers for each bore size. After installing a bushing like Dave describes, I can turn the bushing concentric, then use the steady rest. All this work adds cost a lot of people dont want to pay for. They cant get the juice without the squeeze.

 

[WSnyder]

Yep, if it won't fit in the headstock there's an up-charge for short barrel muzzle work

 

[tobnpr]

Yup. Tapered sleeve is the only way to get the bore concentric to the OD.
Little trick (for me, anyway) is that I'll drill/straight bore to a little over the barrel OD, put release agent-just like bedding- on the barrel to just behind where the tenon will be, put epoxy inside the sleeve, slide it down and let it set up.
For me, faster than measuring and cutting a taper inside.

 

[clowdis]

You can strip the receiver and chuck that in the 4 jaw. Indicate about the barrel shank with the muzzle running in a live center of the tail stock. Then just thread as normal. Don't push the live center in too hard or you may create a burr on the rifling.

 

[LVLAaron]

What walt said is important. I'm pretty picky about making sure suppressors are aligned correctly. I wont debate methods... just make sure you check the alignment of the suppressor. I'm scared of a lot of problems I might cause... Damaging a suppressor is top of my list.

 

[ELR LVR]

I am interested in seeing how you guys are setting up these short barreled rifles for threading the muzzle and keeping the bore aligned for suppressor use. I am getting more and more people wanting these 20" and shorter barrels. Currently, the distance from my outboard spider to the face of my spider chuck is 20". If I can get the barrel off I just set it up in the Viper rest and get it done as I normally would no big deal. The problem I am having is I just had a guy bring in a Howa 1500 that has a factory 20" sporter barrel on it. Try as I might I can't get that damn barrel off so I am interested in seeing how others would handle this project or if you would just tell the guy he is out of luck.

4 jaw and a steady rest or 4 Jaw and a Live Center
Chuck the Action in the 4 Jaw with Brass or copper Shims
you can steel wool any brass marks off afterward
steel wool does not affect bluing (unless you get agressive for a half hour)

 

[ELR LVR]

You can strip the receiver and chuck that in the 4 jaw. Indicate about the barrel shank with the muzzle running in a live center of the tail stock. Then just thread as normal. Don't push the live center in too hard or you may create a burr on the rifling.

This is very true, a burr is easily formed from the live center
once I thread in the live center
I usually then steady rest on the threaded portion, and recut a nice fresh crown which eliminates any possible burr after freshening up the crown

 

[Carl S]

Most of the time I remove the action.if not I cylindrical grind a mandrel if I haven't got one that fits.if you don't want to run a steady rest on the barrel od.because of marking it up.you can turn a fitted pin of your material choice with a shoulder and a center drilled in it.slide it into the muzzle and run a live centre in it.then cut your required thread.if you want to recrown the muzzle screw a cap on your thread and take a truing cut.set your steady rest on the cap and recrown.