The Home Machinist!

I am new to machining and have a small grizzly 10X22 lathe. I need to thread some rifle barrels for suppressors. What is the best way to hold the barrel in the lathe to turn accurate threads concentric to the bore. My plan right now is to load the barrel through the head stock (4 jaw or 3 jaw chuck?). Utilizing a crown saver and a Liver center in my tail stock. I was also told to make a ring of solid copper wire around where the jaws clamp the barrel so that the barrel can pivot at this point. Do i need a spider on the other side of the head?

a spider will be most helpful a quick check of you tube and brownells or midways videos
will give you lots of suggestions

I have been searching you tube for hours now and didnt find any really usefull info. Could you elaborate on why the spider is used?

here are a few links to get you going

http://garagegunsmithing.com/index.php? ... d=54#p1765


here is a video link about a muzzle break threading project, you will have to look at several short clips but you can get some ideas

Use a 4 jaw chuck for indicating a barrel for threading a suppressor.

A spider is the outboard end of the lathe spindle that has been drilled and tapped for adjustment screws, but many people fabricate one that just slips into the spindle bore and is held in place with set screws, then uses the longer brass tipped screws to manipulate the outboard end so as to properly align the bore. Check out the Grizzly web site for the G4003G. They have a photo of the spider on the end. Or refer to one of my photos below. I don't have a photo of a home made one.

Supporting the barrel at the crown, with a crown saver, does not necessarily guarantee that the threading job will be concentric with the bore. I have been down that road and was not satisfied. I also made my own crown saver with a long shaft to center the bore, and it still was not nearly as accurate as using a pin gage with a dial indicator.

I now use the long shafted crown holder to suspend the barrel while beginning to tighten the barrel in the 4 jaw chuck. It keeps the protective spacers in place until I can begin to dial in the bore. It seems to pre-center the bore. But it is not good enough for indicating.

The bore should be indicated to run true from the crown out at least 1-2 inches on a pin gage.

Here is a set up for an AR-15 barrel that will not go completely through the headstock. I used a tight fitting brass mandrel in the chamber to allow it to reach my outboard spider. An aluminum bushing pre-aligns the barrel for the spider screws.


This is a 10/22 setup for short barrels, where the chamber end is held stationary inside the spindle of the lathe. I found the set up so accurate that no manipulation of the chamber end was necessary. The bore would run true all the way out to the end of the pin gage.



Don't use a copper ring on barrel with a black mat finish. It is a bitch to get the copper residue out of the finish. I could never make it disappear.

Don't use a copper ring on barrel with a black mat finish. It is a bitch to get the copper residue out of the finish. I could never make it disappear.

Did you try a copper removing bore cleaner?

I think I tried Hoppe's Benchrest copper solvent, but I don't remember everything I tried. I just know I will always use aluminum on a barrel with a black mat powder coat finish. I swore off the copper just for that reason, it wasn't worth the trouble.