Gunsmithing Need advice from Master Gunsmiths

[Jperk0278]

I just observed my father, who is very meticulous, but by no means a professional machinist, thread and chamber a .17 Mach IV barrel to fit into a run of the mill Remington 700 action. It took him about 5 hours on his Grizzly lathe but the end result was very nice. He’s done this many times with solid results.

My question is, can this job be done as well on a manual machine as it could on a modern CNC lathe with an expert operator, although it would likely take a good bit longer? I’d like to learn these skills, but I also like high end results. My idea is to buy a premium action, barrel and chassis and create something that shoots very well. However, if there is no way to come close to what a top notch gunsmith can achieve in a modern shop, I’ll have to rethink this build.

 

[Rubicon Precision]

Without having any numbers to back this, I’d bet money more bechrest matches are won with rifles chambered on manual machines than CNC. Not necessarily because manual machines are more accurate, they are easier to justify for most shops financially, therefore more are in use.
At the same time, there’s no reason fitting barrels on a CNC machine is inherently less accurate.
So to actually answer your question as someone that currently chambers on a CNC turning center, yes, you can chamber a barrel just as good on a manual lathe as on a CNC.

 

[Jperk0278]

Thanks for the quick response, Rubicon. Part of this, of course is an interest in developing new and valuable skills. My machine room experience has been limited to a few 80% AR projects on the mill so far and I know this is a completely different ballgame.

 

[Holescreek]

I've been a machinist for most of 48 years but have only been home smithing for about the last 10. You don't need fancy/new equipment for barrel work but the job is a lot easier to do on a good lathe with the right proportions for the barrel work to be done. Your father is a valuable resource given his experience and equipment at hand. CNC machines are great for repetitive ops but I wouldn't use one for barrel work unless I didn't have access to my manual lathes. Since you're purchasing everything but the barrel the job is pretty straight forward assuming your father also has the install tools. The amount of work you're looking at depends on what state of completion you buy your barrel in. Are you buying a blank and performing all turning ops or a pre-contoured blank?

 

[Jperk0278]

Haven’t gotten that far yet, Holescreek. My dad buys Douglas barrel blanks and then threads and chambers with PTG reamers and then cuts and crowns the muzzle. Not sure yet on the barrel profile.

 

[LRI]

Op, the answer lies in your scenario. "5 hours..."

If you are trying to feed yourself/family in this trade, manual machines reveal their ceiling pretty fast. It's just difficult to use one efficiently enough to earn a buck while also doing a good job.

This is truly where automation laces up the sneakers and starts putting distance between itself and a manual machine. 15 or so years ago I began messing with this and I was labeled as a half ass hack for it. The sacred cows of the BR world came out in droves to chastise me. My argument has always been that you are willing to trust your family's life (and your own!) to a cnc machine whenever you step on any commercial jet. Why on earth would anyone then think you can't do the same with a rifle? I've asked that 15+ years now and I still do not get a credible answer...

Long story short, the industry has evolved and the serious guys aspire to have a computer driven spindle on the floor. None of this however has anything to do with actual quality per say. It's more about time management. The "quality" comes into play when its time to replicate the process. If you throttle this barrel and want a new one, can your Dad replicate it down the road? I'd venture to guess that he can. No issue there, but what if he had 15 or 20 of em to do and had a hard coded deadline to adhere to? That kind of pressure is the dark cave where mistakes lurk like vultures. CNC stuff just allows a guy to manage the time better and still deliver the same level that folks expect. The payoff for guys like me, Robert, etc is that it puts cashflow into our businesses and that allows us to grow and expand the number of services and continually improve the quality. Doing the same ol thing day after day with no forward momentum is how you die a slow and agonizing death in this trade.

Hope this helps.

C.

 

[Jperk0278]

Thanks Chad. Appreciate the input and I understand the wide gulf that exists between manual machine one-offs and CNC production processes. I also appreciate that shops like yours are able to produce high end results as efficiently as possible. We all benefit from that.

 

[Ledzep]

I just observed my father, who is very meticulous, but by no means a professional machinist, thread and chamber a .17 Mach IV barrel to fit into a run of the mill Remington 700 action. It took him about 5 hours on his Grizzly lathe but the end result was very nice. He’s done this many times with solid results.

My question is, can this job be done as well on a manual machine as it could on a modern CNC lathe with an expert operator, although it would likely take a good bit longer? I’d like to learn these skills, but I also like high end results. My idea is to buy a premium action, barrel and chassis and create something that shoots very well. However, if there is no way to come close to what a top notch gunsmith can achieve in a modern shop, I’ll have to rethink this build.

Yes. You can do just as good a job on a manual that you can on a CNC (assuming spindle bearings are in check, properly rigid setup etc...). Setup is setup. The last barrel I chambered on a manual machine I dialed in to show no TIR in 2 locaitons about 2" apart. IIRC for example, LRI indicates 1 position and lets a collet in the spindle bore handle the alignment. It took me an afternoon to do 1 barrel. Probably 3 barrels could've been done in LRI's shop in that time. It's a theoretical argument as to which way produces better results.

 

[1moaoff]

Truncated threads!!!!!

 

[...]

all of my chambering has been done on manual lathes....im good at machining but by no means a "Master"......

honestly, running a chamber reamer is pretty simple stuff.

 

[Rubicon Precision]

Truncated threads!!!!!

They can be done on a manual.

 

[TresMon]

I'm surprised at the machining times stated here. I must be faster than your average lathe man. But I was a manual machinist for over 20 years....they crack the whip over you every single day because the quicker you can get the part done the more profitable it is to the shop owner.

 

[Jperk0278]

I'm surprised at the machining times stated here. I must be faster than your average lathe man. But I was a manual machinist for over 20 years....they crack the whip over you every single day because the quicker you can get the part done the more profitable it is to the shop owner.

Tresmon,

I understand what you’re saying. I’m looking at this from the point of view of threading, chambering, and crowning at Barrel blank for the first time. At some point, I’d expect to get faster at it, but being a newbie, and wanting it to be as close to perfect as I can make it, I’ll be very patient with it. Out of curiosity, how long do you figure it would take you to do this?

 

[Rubicon Precision]

Tresmon,

I understand what you’re saying. I’m looking at this from the point of view of threading, chambering, and crowning at Barrel blank for the first time. At some point, I’d expect to get faster at it, but being a newbie, and wanting it to be as close to perfect as I can make it, I’ll be very patient with it. Out of curiosity, how long do you figure it would take you to do this?

If you are just doing it for yourself, it is a hobby. Some people spend years rebuilding old cars in their garage. Some people spend a day fitting a rifle barrel in their garage. If you are doing it as a hobby, that time spent is the enjoyment. Knowing you did it yourself is the reward, even if it does take you a good part of the day. If you are looking at it as a hobby, it really doesn't make much sense to dive into the CNC stuff, provided money is a concern.

 

[Jperk0278]

If you are just doing it for yourself, it is a hobby. Some people spend years rebuilding old cars in their garage. Some people spend a day fitting a rifle barrel in their garage. If you are doing it as a hobby, that time spent is the enjoyment. Knowing you did it yourself is the reward, even if it does take you a good part of the day. If you are looking at it as a hobby, it really doesn't make much sense to dive into the CNC stuff, provided money is a concern.

Nailed it, Rubicon. At this point, I’m more interested in seeing how well I can learn to do it as opposed to doing it quickly. I have no aspirations to do this for a living. I’m just fascinated by the process.

 

[TresMon]

Tresmon,

I understand what you’re saying. I’m looking at this from the point of view of threading, chambering, and crowning at Barrel blank for the first time. At some point, I’d expect to get faster at it, but being a newbie, and wanting it to be as close to perfect as I can make it, I’ll be very patient with it. Out of curiosity, how long do you figure it would take you to do this?

Bro I wasn't giving you a hard time. I get that you have not done it yet. And you quoted no times, for yourself, in your OP..so My response wouldn't apply to you from that angle either.

My response was pertaining to time quotes or units/day that showed up in others comments.

While you are learning, I'd be more than willing to answer questions for you, explain how to do something if you're unaware....etc. etc. However I'm sure so long as your dad is available to you each time you need him he'll have it covered. I'm just offering friendly help.

And yes....in regarding to making a part or completing a barrel, manual machines are just as accurate as CNC.

 

[Jperk0278]

Bro I wasn't giving you a hard time. I get that you have not done it yet. And you quoted no times, for yourself, in your OP..so My response wouldn't apply to you from that angle either.

My response was pertaining to time quotes or units/day that showed up in others comments.

While you are learning, I'd be more than willing to answer questions for you, explain how to do something if you're unaware....etc. etc. However I'm sure so long as your dad is available to you each time you need him he'll have it covered. I'm just offering friendly help.

And yes....in regarding to making a part or completing a barrel, manual machines are just as accurate as CNC.

No offense taken, TresMon. Appreciate your input.

 

[Ledzep]

I was far from in a hurry. Taking my time and searching for tooling in between steps it took 3.5 hours or so to turn/thread/chamber the breech, then flip it around and indicate and thread/crown the muzzle. Rubicon hit the nail on the head. It could've taken 8 hours and been of no consequence.

 

[Jperk0278]

Ok gentlemen, I purchased a couple of Kelbly actions, Krieger rbarrels, XLR chassis and a PTG reamer
so that both my son and I could learn from my dad how to thread, chamber and crown the barrels. We put them together yesterday and were very happy to see that they are both half minute rifles. We spent a lot of time on the process, but it was one of the most enjoyable projects I’ve ever done. Looking forward to doing it again.

 

[want2learn]

that's so awesome...what a fantastic opportunity and experience. i would cherish that memory.

 

[A&8's]

I chamber on a manual lathe. No DRO, either.
But, I’m no ‘Master’. Just a guy who’s done it a few thousand times.

 

[1moaoff]

They can be done on a manual.

I understand that but having it in a program is the easy button.

 

[Rubicon Precision]

I understand that but having it in a program is the easy button.

This is true, kinda.

 

[ken226]

This is true, kinda.

Yea. Pushing "Cycle Start" is easy.

Solid modeling the tenon and chamber with Solidworks or Inventor then creating the toolpaths with HSM, takes as long as chambering on a manual machine.

But, you only have to create the program once per model/caliber.

I suppose a good cnc machinist could get through most of the tenon and threading using canned cycles.

 

[Rubicon Precision]

Yea. Pushing "Cycle Start" is easy.

Solid modeling the tenon and chamber with Solidworks or Inventor then creating the toolpaths with HSM, takes as long as chambering on a manual machine.

But, you only have to create the program once per model/caliber.

I suppose a good cnc machinist could get through most of the tenon and threading using canned cycles.

It’s a simple barrel tenon. I hand write all my programs. I guarantee I can hand write a barrel program start to finish and run it faster than someone could do one on a manual machine.

 

[ken226]

It’s a simple barrel tenon. I hand write all my programs. I guarantee I can hand write a barrel program start to finish and run it faster than someone could do one on a manual machine.

I don't doubt that you could.
Maybe I could too, but I've never timed myself at it. I can do it on a manual lathe fairly quick though.

For writing a CNC chambering program, The Threads, counter-bore, chamfers, tool change for the reamer and chamber reaming z movements, and any peck moves, add enough to the program time that I would doubt my own ability to hand write faster than manually threading and reaming.

But, that's a non-issue for me. I drew solid models for most common tenons, chambers and extractor cuts a long time ago. I usually generate toolpath programs from those. With the modeling work already done, it takes a couple minutes to generate a program with HSM.

Whether writing g-code, generating a program with CAM or using canned cycles, I was just pointing out that it's not quite as easy as pushing an "easy" button.