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CNC lathes

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20 October 2003, 17:24
ALF
CNC lathes
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21 October 2003, 03:43
Groove Bullets
Alf,

Milling is done with an "end mill" on a "Milling Machine". Turning and Facing for your purpose is done on a lathe.

I wouldn't want to attempt to manufacture a bullet on an "Engine Lathe". You need a CNC (computer numerical control) Lathe. I have seen small CNC Lathes that are used in Tech Schools that are light duty and used for teaching purposes. For an individual, this would work fine. You will need to learn to program the machine. If you live in an area where there is a Technical School you may want to take a "Machine Shop" class to get familiar with all the measuring tools as well as machine operations. Some Technical Schools offer CNC training - specifically.

I don't have any idea what the cost of one of these little CNC lathes would be. You could do a search on the net for CNC Lathes. You could more then likely pick up a used CNC lathe at a very low price. Right now, with the industrial economy in the toilet used machine prices are at an all time low.

If you are thinking of using copper to make bullets you will pay through the nose for material from supply houses. The mark-up on copper is extremely high going this route.

We order copper by the ton directly from copper mills.

If you want possible sources for buying a machine, send me an e-mail. I will direct you to possible sources.

Don [Smile]
21 October 2003, 05:26
Saeed
ALF,

The machine we use costs around $19,000, which is really right at the bottom of what CNC machines cost.

It is a very small machine, and we have to finish the bullets we make on it normal lathe.

No matter what we have tried, we could not get it to cut the bullet off squarely, it always left a sort of small nipple.

So we make the bullets on that machine, and I finish them off on my normal lathe.

This machine was supposed to be used by schools, to teach CNC, and not to be used for any sort of long production.

It does its job for us, but rather slowly. I would imagine it takes about 5 minutes to make one bullet.

It might be easier and cheaper for you to have someone make these for you.
21 October 2003, 18:38
ALF
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22 October 2003, 01:57
Pete E
Alf,

Can I ask what you want the bullets for? I ask this because it would seem there are easier/cheaper ways to make bullets which will take 90% of game available. For the big 5 I would say that it would be cheaper to take a trip to the States every so often and stock up with premiums providing of course you can import them.

As you suggest Primers are the real critial bit. Any government who wants to restrict/ban firearms would probable be best targeting primers...

Regards,

Pete
23 October 2003, 18:27
Pecos41
Pete, you are right on about your fears.

But there is one avenue that IMHO all shooters should consider about bullets and oppressive regulations. CAST bullets. It's damn near impossible to take away cast bullets from people. The ingredients and process are too simple. And the performance is plenty good enough for most purposes. All the guns that "won the west" shot cast bullets. [Wink]

And they about wiped out the buffalo herds with them...and the griz etc.
23 October 2003, 19:21
ALF
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24 October 2003, 04:23
andrew375
Instead of buying a lathe why don't you contract the job out to one of many small engineering companies that are about. Companies with automatic lathes are always looking for this type of work, which is ideal for the machine and will keep it working during slow periods. The problem is cost; ignoring set-up costs and materials the cost (in the uk) would be around �0.40 / bullet. This is with you providing the program on disk.

I've made bullets on a lathe, specifically a copy of the Sierra .375, 300gr. SPBT GameKing for long range target shooting, and they were very successful but in the end I went over to cast.

The material I used was normal brass bar, the cheapest on the rack; any of the bronzes would work too. There is a discussion of bullet materials on the fifty-calibre owners association web site; they also use bullets made of mild steel.

In machining the bullets I arrange the cutting path to start at the base, that is the nose of the bullet was closest to the chuck. The first cut trued the base and the end of the cut that formed the nose resulted in the bullet dropping off the bar. Only one cutter pass was needed, total cutting time was around 40 seconds; less time than it took to reset the lathe for the next cut. This is why you need a machine with automatic bar feed to make this a practical proposition for anything like mass production.

For round nose bullets the job is even easier just make, or buy, a radius tool, skim the bar down to diameter to the required length and then plunge in, cutting the bullet nose and parting off at the same time.

To be honest though you should get into cast bullets, after all any shooting is better than non and with a bit of work you can get very good accuracy at the same velocity of jacketed with most cartridges. For instance with the NEI .375-280-gc (actually 300gr.) I can get 1.5-2 moa at 2600fps with no problem in my .375 H&H.

In my .223 I shoot the NEI .224-71-gc at up to 2600 fps and sub moa accuracy and in the .308 I can put out the Lee .309-200 bullet at 2700 fps, which is higher than that for the equivalent jacketed bullet!
25 October 2003, 10:26
Pete E
Alf,

quote:
To shoot with?
That makes sense then, just pay your $19,000 for your CNC lathe and go make your very expensive bullets [Roll Eyes]

Pete

[ 10-25-2003, 01:28: Message edited by: Pete E ]
25 October 2003, 11:15
outlawsix
I visited Barnes Bullets 3 weeks ago and was surprised as to how small their CNC for the solids is. It was maybe 18"x 2'. They said it turns out a bullet every minute. You could always contact them directly and see what brand and model it is then check around on prices. You may get lucky.
25 October 2003, 12:47
ALF
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25 October 2003, 13:37
outlawsix
I ment just call Barnes to find out what the make and model is of their CNC machine so you might be able to find one like it that will turn out bullets quickly and accurately.
25 October 2003, 17:52
Pecos41
ALF, somewhere around here is a member by who goes by the name Todd E. He is an expert on lathes. Why not contact him? I'll bet he can help.
25 October 2003, 17:58
ALF
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26 October 2003, 07:39
Pete E
Alf,

The reason I asked was simply that there are other more cost effective ways of producing bullets other than cnc lathes but it depends on what you entend shooting with the bullets.

However if you were thinking of setting up a small business the investment in a CNC might be more easily justified or if the expense could be shared between a group of shooters...

Have you considered swaging jacketed bullets? I don't really know anything about the process, but I think Mike375 had gone into it quite a bit for similar reasons to you. I am not sure how versitile it is, but that would just leave you short of solids suitable DG...

Of course swaging would not allow you to experiment in bullet profiles like a CNC lathe would, but it could be a cost effective solution for 90% of your guns/circumstances...

Regards,

Pete
26 October 2003, 07:49
Pecos41
Pete, I think most of us on this forum are past, present or future bullet swaggers. Getting the dies for this and building your own jacketed bullets thru swagging is a LOT more versatile than a person might think. There is a whole range of sizes, weights and shapes one can produce simply by varying cup length, core weight or alloy, and adjustment of the forming die.

About the ONLY thing I can think of making bullets on a lathe really has to offer is the ability to make bullets out of materials not normally found in the bullet market. But if we look at the Cost VS the Effect of making bullets this way, it looks like a rich man's toy to me and no way it could ever be justified. JMHO
28 October 2003, 07:52
akv
What kind of jacket strength were you guys getting from turned heads? Swaging would seem to offer the additional advantage of a cold work process, thereby adding strength to the head, as opposed to the uniform grain structure one would get from turned heads? I'm more familiar with steels and aluminum, but would think that the same principles would apply.