Threading a barrel without taking barrel off?

[Stgraves260]

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I always assumed the barrel needed to be taken off in order to thread the muzzle ?
Is this correct, or is it like I just read on a different thread?
"Any gunsmith that can't thread a barrel without removing it shouldn't be a gunsmith."

I wouldn't use a tap and die set. The barrel comes off to be set in the lathe. The barrel has to be perfectly centered on the lathe so that when the barrel turns it is properly balanced so that when the cutter starts to cut the threads they are machined properly. It's just what most Smith use. Now if the Smith has a mill, the barrel will not turn. The tool with the cutter on it will turn. A mill would be an expensive machine just to thread a barrel for a break. A lathe is more commonly used by a gun smith because it it used to make probably 98% of the gun. JMO.

 

[Teddy Martin]

If the gunsmith lathe bore is big enough to slide barrel though the chuck with spiders on back side you can you can thread muzzle I have many of times you need to take scope off work it with slow RPM as long as the barrel is long enough

 

[Mram10us]

OP,
If you get answers from guys that do this work, the vast majority will NOT remove the barrel from the action unless they HAVE to. There is zero advantage to taking it off and it won't wobble at the slow speeds used for threading.

 

[thwatson2]

Barrel does not need to be removed

 

[Gcan]

I always assumed the barrel needed to be taken off in order to thread the muzzle ?
Is this correct, or is it like I just read on a different thread?
"Any gunsmith that can't thread a barrel without removing it shouldn't be a gunsmith."

i do that quite often. Set up barreled action in double spiders. Indicate muzzle to .0001/.00015" using a range rod. Be sure to indicate runout as close to muzzle and as far out on range rod alternately using both spiders to adjust. When u have zero in both places turn and thread it. Remember range rods are tapered so don't react to indicator going +/- when you move back and forth. Just deal with runout.
Its always worked for me.
Cut largest thread you can. 3/4 on 30-338. 3/4 or 5/8 on 6.5 and below.
You should take the opportunity to address the crown also.
Turn the thread back to minor dia from the crown .050-.060" so u have perfectly concentric crown.

 

[rem.xp100]

Depending on the rifle brand, type of action, length of the barrel, size of the Lathe, size of the chuck and many more parameters, the action can be removed or doesn't have to be removed to thread the muzzle.

It is a decision that the smith needs to make based on many things, it is not a rule cast in concrete that it cant be done any other way. Also sometimes it may be a matter of convenience or just the best way to do the job accurately. Again, the smith should decide this not the general public. There will always be more than one way to do many things, but there is only one 'best' way for a particular task based on the end results.

J E CUSTOM

Spot on as usual.

Some of us have tools that other shops don't have that allow us to do work in ways others can't. Doesn't make either one right or wrong. I rarely take a barrel off these days but I use a HAAS TL2 with some custom fixturing and a True Bore Alignment System that allows me to align co-axially with the bore with or without the receiver attached so there is no reason to remove the barrel and add extra work if it's not needed.

 

[25WSM]

Been doing it for 30 yrs. I never take a barrel off unless it has to come off. I can do a muzzle or crown 3 different ways but like to do it in the headstock. I made a very thin spider chuck for the front that allows me to do as short as 18 inches. Any thing 18 and longer just goes to the headstock. I charge 75 to do a crown and 125 to crown and thread. I would never thread for a brake and not touch up the crown anyway. If I had to take a barrel off you risk marring the barrel in the clamp. Risk marring the receiver with the wrench. And taking factory barrels off is not the easiest thing to do sometimes. Barrels on target rifles come right off easily and I do take them off. Most short range bench guns have the receiver glued into the stock. So barrels do need removed for those.
If you want to try at home by yourself you can. But any smith worth a salt is going to get you a crown that is true within.0005 and that's pretty dang straight. Your gun will love you for it.
There are lots of stuff you can do as a diy but metal work is not really one of them unless your a machinist and have machines.
Shep

 

[jimirwin]

I always assumed the barrel needed to be taken off in order to thread the muzzle ?
Is this correct, or is it like I just read on a different thread?
"Any gunsmith that can't thread a barrel without removing it shouldn't be a gunsmith."

I question the quote provided above.
I have used a set of tools that referenced on the bore at the muzzle via a very close fitting dowel, allowing a proper crown, and reduction of diameter, and threading. All done by hand.

Trying to do this job free-hand is a fool's errand. Might get away with it for a brake, but not at all likely to work well for mounting a silencer.

 

[freddiej]

Threading is a slow rotational operation on a lathe, so the bare receiver can be left on the barrel. this means the trigger, scope/bases/rings, and bolt must not be in or attached to the receiver. No, the barrel does not need to be pulled from the receiver to be threaded at the muzzle, you will need to center both ends of the barrel to thread the barrel properly. takes small cuts and have the threading cutter perpendicular to the bore.

 

[Sgt. grizz]

I will thread a barrel with the action on if I can fit it in my lathe. Some times depending on the length I will have to take the action off

 

[IdahoCTD]

Threading is a slow RPM operation but turning the OD prior to threading really isn't. With HSS you can slow things down but carbide usually likes more RPM's. It's really hard to not have balance issues at high RPM's if the trigger and other things are left on the action. Remington's, and other fairly round receivers, do quite well at high RPM's if everything is removed though.

 

[Mram10us]

Threading is a slow RPM operation but turning the OD prior to threading really isn't. With HSS you can slow things down but carbide usually likes more RPM's. It's really hard to not have balance issues at high RPM's if the trigger and other things are left on the action. Remington's, and other fairly round receivers, do quite well at high RPM's if everything is removed though.

Well said from a pro. I should have clarified that the receiver and barrel are the only things left. I only turn the OD at 660 and thread at 90 cause I'm scared to crash Not all of us have monster cnc machines, Nathan

 

[IdahoCTD]

That wasn't aimed at anyone in particular Mike. People kept saying threading is a low RPM operation, and it is, but to get there you need more RPM's and even 660 RPM's with a out of balanced receiver attached can cause issues.

 

[Will Gray]

I have done a few on my old Craftsman lathe but the barrel needs to have a taper so it is no more than 3/4" diameter 15" from the muzzle with no fixtures on the barrel. I put the barreled action (scope too) through the headstock and using a dial indicator and a range rod, get the barrel set then thread. If the barrel is too big, I take it off the action and thread between centers. I only remove barrels if replacing them using a Savage style lock nut for adjusting the headspace.