Thanks for putting narration to explain what is going on. There are lots of videos that show machining, but they only make sense if you already know what's going on!
While you have the shank end of the barrel centered, and have turned the threads, that's an ideal time to use a floating reamer holder in the tail stock and chamber the barrel. Otherwise you'll have to do the centering setup twice. A Savage barrel can set the headspace with the barrel nut, so the headspace can be adjusted on the action. On rifles without a barrel nut the barrel can be short chambered in the lathe, then finished on the barreled action. When turning the profile on a barrel you can avoid too much chatter by stepping the barrel blank out of the chuck and roughing the contour in short segments (the opposite direction the video shows for contouring a straight bull barrel). Then do the final contouring between centers. If your going to sand on the barrel between centers, cover the ways with some rags of other covering to keep the grit off the ways. This was a good and informative video.
Good job... Excellent thinking that few people know these days. I am a retired machinist with over 40 years of experience so I recognize good technique when I see it. It would be nice to have a steady rest but you can build a good follow rest that will work better for you with a little patience. Most lathes already have holes drilled and tapped for a factory supplied one. Find a place to mount it to the saddle and just touch the barrel with the pads in order to dampen any vibrations as you profile the barrel any way you want. You can program the desired taper if any and hold the diameter as you gently work the top and back pads. Brass or nylon will do nicely. Leave a 63 finish a couple of thousandths over the finish size and work the diameter with emery cloth to a 32 finish. This will save you a lot of time after the first barrel and improve your already excellent quality. Keep up the good work and happy machining to you. Don
Thank you for this comment. I have dreams of turning my shop into a working machine shop... Someday. As for now I'm 1.5 years working in a machine shop, & learning daily..but it's gonna happen. As for now I love this work, maybe I will soon stop being a chicken & turn my lathe on
thanks for the video! im definitely looking into getting into this as i've been getting into parts kits recently that *dont* have barrels readily available. Maybe ill even make some extra barrels and sell them :)
Thanks for the details, they are very informative. The camera is getting dark because the automatic light sensor is tripped whenever you get the glare from the ways hitting the center of the picture. The choices are to move the light, cover the ways with some paper to darken them. or mess with the controls on the camera to allow 'backlighting'.
One suggestion, since it is from a blank and not a re-chamber. You could put it between centers and turn the OD parallel to the bore. Then use a spindle liner on the muzzle end with a slip fit on the OD that you turned. Then when you chuck up the breech end and indicate it, the muzzle end, chamber,and breech features will have very close TIR and concentricity to the bore on both ends.
That is the exact way real gunsmiths told me how it is done when going from a barrel blank to finished contoured barrel. With spindle liner, you mean a outboard spider right ?
The bed rail is messing with the F stop on your camera. Just put a dark rag or towel over it when filming to block the reflection of the ambient lighting. Agreed, Eric has it figured too. Camera is set to spot metering vs. average metering meaning the F stop is going to change based on a narrow margin only within the center of the frame. Average will have more tolerance for light and dark areas in the frame "averaging" the F stop metering.
Question........ Why not mount the barrel between centres and centre the shank dead on to the bore? Then no matter where the bore is in relation to the blank the shank will be dead centre. You could flip it end for end and centre the muzzle the same way using the 4 jaw as an adjustable lathe dog. This will be accurate to less than half a thou without even using a dial gauge. Quick and easy,
I like emery cloth, though generally its frowned upon to use it while the part is still in your machine. The particles are abrasive and very fine, so they cause premature wear on the ways, or just as bad, your spindle.
Really cool video! The camera is probably picking up a reflection from the rail and trying darkening to compensate. I'd consider covering the rail during shoots or re-positioning a light to avoid the glare.
Nice indicator, I would just run that long tip and gauge off the lands and grooves. That swarf scares me laying on bed like that near chuck. Bump them feed rates up just a suggestion. nice video and machine.
Because his headstock is too big for the barrel to protrude out the spindle bore, which disallows the use of a spider for his second point of adjustment. You can get pretty close with a four jaw, but not close enough for things like barrels, where you can't have much runout and the part is long. As for indicating off the bore, he runs into the same problem. If his barrel was long enough, he could indicate off both ends of the barrel. Not so in this case. so he'd only have one point of reference.
Sir, you camera is going dark because it is spot metering on the center of the picture which is a very bright metal bar of sorts. When the meter sees that very bright item it darkens the picture to compensate for the brightness of the bar. If you are able to change the camera's metering schematic to center weight average, matrix, or something besides spot metering it will correct the trouble.
I hope you are not suggesting that the bore is axially centred with the outside circumference. The word must be done with the witness being the bore, The outside is ground and in many rifles it is not concentric with the bore
Looks like you know what you are talking about, 1 question, why worry about the out side of the barrel ? why waste time, I would just indicate the bore.
The camera was going dark cause of how it was light metering. It was probably set on spot metering and every time it would meter on the reflective ways it would darken. You need to set it to overall avg. or set it manually.
How funny... I just typed the same thing in not seeing that you had already done it. Both of our posts look like they were typed by the same guy... ha ha. My compliments.
Your image gets dark when you the AE 'exposes' the entire image for the brightest spot (glare on rail). People should often set that manually (along with zoom) and put the camera in a stationary location.
Is your indicator calibrated for that length of needle? the longer the needle, the less accurate the indicator, so if that needle is 3 or 4 times longer than the stock one, your measurements will decrease in accuracy by a factor equal to the ratio of the length difference. so what appears .0003 is closer to .0012 or .0016. i'm a machinist not a gunsmith so i'm not completely sure how much a thou affects accuracy with regards to ballistics and baffle strikes, i just know the government freaks about .0005 deviation in concentricity when it comes to aviation.
How's the 3 Jaw chuck workin for ya? Hoping the .338 works well for ya , I can tell you that round is a trip! Wondering if you'll take barrel Turning jobs as "side work" ? Anywho , best toy you and yours !
He'll make the threads run out so when it's tightened up, it will be 12 o'clock. Seems like a lot of work but those used to ancient machines are used to it.
why do you bother squaring up the barrel perfectly if you are going to re-square it to the bore anyway? I do like the barrel rig though. Tell me, do the ends of the cap screws mark the barrel or do you reface the outside of the barrel afterwards?
man barrel threading seems scary this may just be something i have a professional to do i have access to a friends lathe however i dont really know how to work one id have to talk to him and see if it would even be possible for him to set up a saiga to get threads on it
I'm thinking of turning my own bullets. Your camera is metering off the highly reflective rail (not sure what it's called) look at your video and you will see that when it goes dark the "rail" is perfectly metered. If you put a cloth over it when you're recording you wont have this problem. The music is very distracting also. I hope this contributes to your excellent tutorials.
Just a humble suggestion, but if you put one of those spiders on the far side of the spindle where the other end of the barrel is, you'll find it easier to center as the adjustments will be finer. Also you wont have to worry about the free end of the barrel whipping around and throwing off the center during cutting.
How do you know the centre of those brass bushings are concentric to the exterior of the bushing? Did you bore it out? I'm guessing you made the bushing because you weren't able to find carbide the correct diameter for the barrel ID?
Running out a little bit and it does not matter, are you kidding, except for head space it is the most important thing going. You are going to cut a chamber that is "On Center" with the center line of the lathe but the center line of the barrel is pointing some place else. Unless the center line is true and the O.D. is out.
+Legion Prime Think about this for a short minute. The center line of the lathe is where the reamer is going to cut, the center line of the barrel should be true to the CL of the lathe, his barrel is wobbling so there is no way the two CL's can be running true. That means that the chamber is not pointed down the CL of the barrel. So the round has to jump from one CL to another, I cut Propeller shafts for Aircraft Carriers many years and we cut them far truer than his work Look at other vids of barrel clambering and you can see what I am trying to get across. 40 years in modern machine shops has taught me better than this.
Why not get a barrel blank, drill the bore and then turn the barrel to the bore? Seems like that would give you a perfect alignment. I'm not a machinist but i was just asking. :-)
a general gunsmith doesn't drill the bore and rifle it... that's for barrel makers to do.. old school gunsmiths did what you suggest but they didn't cut the barrel they put a sleeve on the outside of the barrel and cut it to the bore,,, more steps,, but the best way is to indicate the bore on the barrel and the center line of the receiver....
I'm an "amateur"machinist but doesn't this have bad written all over it? From my experience I would have set up on centers, steady rest the end away from the chuck, and then indicated the bore in, or set up a spider (I noticed that this would not be easy on the lathe in the video but for reference) and then indicated the bore in. Anyone see anything wrong with my chosen set-up that I am overlooking?
If you are chambering a barrel there is no reason to dial in the outside of the barrel first, just dial in the bore of the barrel and save yourself the time.
Wouldn't you just center into the actual center of the barrel? Why would outside diameter matter when you're trying to center off the bore? I'm new to this so just curious.
Because centering to the OD of the blank gets you close first, then you fine-tune to the actual bore axis. Afterwards, you turn the blank down to profile along the same axis as the bore.
very good video and amazing machine !! but i swear your camera looks like its on acid lol the images keep warping in the back round and its super trippy lol
Forgive my inexperience/lack of knowledge (everyone's got to learn sometime), but why wouldn't the following work: Between centers w/dog Or using the 3-jaw chuck and a center in the tailstock
+Damien Gregory You can do it between centers but most lathes that are used in Gunsmithing are not long enough in the bed to allow for this. If the bed was long enough sure. Now the thing is and i see this all the time. there is no reason to indicate between center or do the work between centers. you should only indicate the length of the camber plus 1" or 3" overall which ever is more. Think about it. the bore is not straight not saying the barrel is warped but it is impossible to have a hole in a barrel that is straight within .001" over say 12" so dialing in between centers is useless when you have a slightly banana shaped hole. sure the ends are true to each other but what about the center?? So just indicate the area you are working is as close as you can and call it good. once the bullet hit the rifling it's out of your control anyway.
+Damien Gregory, If you are refering to turning the O/D, either one would work in theory, but you need to watch out for chatter, a running steady would be the best method. Once you had turned the O/D I would then have the whole barrel sticking out of the chuck, with the centre in, and then cut the thread, that way you know that the thread is dead true to the O/D.
Yes you need to use a follow rest too but that is just good machinist practices. Threads true to the OD look good but mean nothing. and you will only be cleaning up the breach end. Barrels that are turned in bulk are done on CNC machines and have collets and hydro pushers like an over sized swiss screw machine.the barrel is advanced out of the headstock into the tool. this allows for fast turning of a long part with no chatter. Problem is the Gunsmith don't have access to these tools.
really interesting but it would be better if you turned off the noise in the background and steadied the camera and fixed the lighting glitch before making the video, but good to watch despite that
Meh, its just a little swarf. The ways were pretty clean and debris clear. Im assuming you're not a machinist because even a small operation will add create significant amount of swarf. ie. machine cut aluminum takes up about 15x as much space as solid alum, so tl;dr it gets everywhere even on a tiny cut.
Thats why we have chip pans... he keeps his ways clean... i personally clean up after every material change so i can do some casting for future projects..
Look into getting a gopro and a stand for it,or a clamp,be easier to film stationary objects :) great video though,other than your camera being a bicuit
