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Need CNC milling machine advice for odd barrel fluting

I think space is at a premium. You also don't want to get too funky with these things. Barrels take very little to stop shooting accurately. Accuracy International did extensive testing in controlled environments and decided fluting wasn't worth it. Unless you have a truck axle barrel and can't make weight in the class you shoot in its probably not worth the risk. However the customer is always right and if they want it they get it.
"Rich" folks want whatever they can pay extra for that they think is "cool", don't care what it costs, and can't shoot anyway, so they don't care about little things like accuracy... :D
 
Another possibility…
It seems like the milltronics partner open mills might be a good choice. Seems they can be had for reasonable prices. I know of a shop that had one of these and they found it to be a good versatile machine.
 
"Rich" folks want whatever they can pay extra for that they think is "cool", don't care what it costs, and can't shoot anyway, so they don't care about little things like accuracy... :D
I used to see the odd fluted barrel on the range especially in 223. Then they upped the weight limit and the need disappeared. Obviously the need for more bling never disappears
 
I'm sure as hell not rich and don't believe in unnecessary or illogical bling. My 6mm ppc bench rest rifle has a straight fluted barrel because it allows a slightly larger & stiffer barrel diameter while still making the 10 1/2 lb weight class. In decent low wind conditions it will shoot 5 shot groups @ 100 yrds well under .100" when I do my part. So there are logical reasons for it in some cases. And some of us even know how to shoot.
 
I didn't machine my barrel, I just bought the components and specified what I wanted done. But it was ball milled by a gunsmith known for producing good shooting competition rifles. And I don't doubt it could shoot well under your .075" since the rifle is still better than the shooter is. And there's lots of ball mill fluted bench rest rifle barrels that have shot under .020" groups multiple times. So I don't fully agree that hobbing the flutes has any distinct or repeatable advantage or far more gunsmiths would be doing it that way and promoting it as a superior method since there's a whole lot of competitive shooters around with some pretty deep pockets. EDM possibly or might? introduce less residual stresses into a barrel being fluted, but I've no idea if that's been tried yet. I'd be surprised if it hasn't though.
 
Wow, thanks for all the info.
You guys a correct I am not a fan of fluted barrels but I’m a even a less of a fan of talking customers out of spending money.

So forgive my incompetence. I am going to google it but what is a hobber?

Numbers wise I am sending out more barrels then I ever thought I would of and the numbers rise every month.

I am pretty dead set on cnc and a 4th axis. I can use it for bolt flutes and other action related parts. I will check out the machines that some listed. It seems that the more wild the barrel looks the better people like it. Truthfully I don’t think people even shoot guns anymore. They are just used to show off to their buddy’s.

I know chatter is going to be an issue…. I had to build a pneumatic steady rest on my TL-1 to counter act the chatter. But after solving chatter on a 28 inch .625 barrel on a lathe it would have to be laughable comparably to solve on a mill.

Any thoughts on centroid?

God Bless,

Dustin
 
Centroid is a control not a machine. if you find cnc machine with fubar control centroid is valid option; if you find a cnc machine with centroid that is valid option; if you plan on retrofitting a manual machine change plans now. You are a business, retro fitting is a fun project like a classic car or model aeroplane*.
*there are exceptions for specialized machines and people that have been in the rodeo before.
 
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EDM possibly or might? introduce less residual stresses into a barrel being fluted, but I've no idea if that's been tried yet. I'd be surprised if it hasn't though
Too slow and you would need a very specific machine. Chambers and magnaport have been done but it's a straight die sinking operation where you can reverse the polarity and mount the barrel off the side of the ram and the electrode on the table to ensure the area being sparked is under dielectric.
 
Wow, thanks for all the info.
You guys a correct I am not a fan of fluted barrels but I’m a even a less of a fan of talking customers out of spending money.

So forgive my incompetence. I am going to google it but what is a hobber?

Numbers wise I am sending out more barrels then I ever thought I would of and the numbers rise every month.

I am pretty dead set on cnc and a 4th axis. I can use it for bolt flutes and other action related parts. I will check out the machines that some listed. It seems that the more wild the barrel looks the better people like it. Truthfully I don’t think people even shoot guns anymore. They are just used to show off to their buddy’s.

I know chatter is going to be an issue…. I had to build a pneumatic steady rest on my TL-1 to counter act the chatter. But after solving chatter on a 28 inch .625 barrel on a lathe it would have to be laughable comparably to solve on a mill.

Any thoughts on centroid?

God Bless,

Dustin
Seeing as you already have a Haas it probably makes sense to get another. I'm no fan but they get the job done. I'll be doing all my bolt camming etc for the actions I start building next year on a SMM2.
 
I am going to google it but what is a hobber?
This one only does 16" between centers (and cutting length) but you could make an extended tailstock. For example ...

Barber-colman-6-10-gear-machne-triple-thread-index-worm-1.jpg



I am pretty dead set on cnc and a 4th axis.
I have thought these would be cool for long skinny light work ... does anyone make something like these in the US ?

bigger

big-4th.jpg

smaller (actually a little guy like this would probably cut your flutes fine, and not take up much space at all. It's also travelling head, stationary part)

small-4th.jpg
 
I despise this video but these were built to do a job exactly like this so might be of interest ... this is dual spindle so two parts at once, they also made a duplex cutter version, and other varieties but all fully automated, for this purpose. No steenkin' electronics :D

 
Are they ground?
No. A lot are polished afterwards. The finish can be pretty variable across manufacturers. This is an industry that runs on old tech. The speciality is to find something that has been done for years repackage it as new and ground breaking and charge an astronomical price for it. It's also a world dominated by hype and bullshit. The original poster sounds like a stand-up guy but there are some snake oil salesmen that make the orange oaf appear like a rank amateur.
 
Centroid is a control not a machine. if you find cnc machine with fubar control centroid is valid option; if you find a cnc machine with centroid that is valid option; if you plan on retrofitting a manual machine change plans now. You are a business, retro fitting is a fun project like a classic car or model aeroplane*.
*there are exceptions for specialized machines and people that have been in the rodeo before.

I second this ^^^

There are a metric shite ton of older cnc knee mils around with dead controls. They are already fitted with servo motors and mounts, high quality ball screws and everything else needed for an easy control retrofit.

The entire set up shouldn't cost more than $10k. $5k in parts for the centroid set up and less than $5k for the machine and 4th axis.

I have $7500ish total in mine without a 4th axis; even less after considering the $ I got from parting out the old control.
 
Poster is looking to do other parts also. I'd start with something better than a knee mill for future expansion if space and capital are available.
 
I guess while we're here I'll run my ignorance up the flag so y'all can have a laugh, but ... when I was a kid I had a Hi-Standard 22 target pistol. It had an extremely heavy barrel for the caliber, like 3/8 to 1/2" thick, something like that. It's been more than a couple of weeks ... I was told at the time this was because mass increased inertia, which I think has been confirmed by physics, both in theory and practice. More inertia in something which you are using to aim a projectile seems like a good idea.

Why would you want a barrel that flopped around like a dying salmon ? Isn't heavier more stable/better in this case ?
 
I guess while we're here I'll run my ignorance up the flag so y'all can have a laugh, but ... when I was a kid I had a Hi-Standard 22 target pistol. It had an extremely heavy barrel for the caliber, like 3/8 to 1/2" thick, something like that. It's been more than a couple of weeks ... I was told at the time this was because mass increased inertia, which I think has been confirmed by physics, both in theory and practice. More inertia in something which you are using to aim a projectile seems like a good idea.

Why would you want a barrel that flopped around like a dying salmon ? Isn't heavier more stable/better in this case ?
You can go with a much bigger diameter and increase the torsional stiffness. Fluting done correctly will reduce mass. Originally fluting was straight now it is mostly helical. A supposed advantage is increased surface area for heat radiation. In target rifles with short strings of fire it's irrelevant.

You can probably tell I have spent far too many years sitting around on rifle ranges with citizen scientists (I'm trying to be polite, they are more like science experiments gone wrong)

Your 22 was probably a bull barrel. I attended a weapons seminar in the army and the sergeant major presenting a lecture said the infantry don't want to hear it but a heavy weapon is an accurate weapon.
 








 
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