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troy_mclure
03-17-2009, 05:35 AM
a guy at the range the other day was shooting cast bronze bullets out of his .308.
he said his brother casts them for higher velocity loads than lead can handle.

the bullets looked kinda cool. i imagine they act like solids.

anybody cast bronze?

Willbird
03-17-2009, 08:11 AM
I highly doubt he was casting them. It is far more likely he machined them from bar stock.

Generally bronze melts about 1750 degrees and pours at 2250 degrees.

Bill

pdawg_shooter
03-17-2009, 08:16 AM
Why bother with bronze? If he wants high velocity with lead all he has to do is paper patch. With the right BHN 3000fps with accuracy is attainable.

z4lunch
03-17-2009, 09:32 AM
What about machining copper bullets??? Like the Barnes X.
Steve

docone31
03-17-2009, 09:40 AM
Wow, casting bronze.
I cannot think of anything harder to do. I cast silver, occasionally brass and bronze.
Swageing, might work, if the prime stock was real close to being swage ready, and annealed.
That takes some real oomph to do.
Paper patching zinc?

Cap'n Morgan
03-17-2009, 11:22 AM
I somehow doubt the bullets were cast - at least not in a metallic mold, since bronze melts at 1750 F (950 C°) and casting temp has to be somewhat higher.

The bullets you saw was no doubt turned from round bar. Casting bronze bullets would be sheer madness...

Shiloh
03-17-2009, 12:03 PM
They most probably weren't. As stated above, probably machined

Good luck doing it in mold for lead. They would most likely have to be cast in sand or some other sort of investment casting. After that, they would have to be cleaned up and then sized. This would be WAY to sophisticated for the average boolit caster to do. Quality boolits and uniformity would be a crap shoot.

From what I've seen though on this forum there are folks with access to some not so average equipment though.

Shiloh

Greg5278
03-17-2009, 12:10 PM
My guess would be CNC Lathe tuned or better CNC screw machine. I am actually getting a run of tuned .500 Diameter bullets made. They will be used in 12ga Sabots. Check out Lehigh bullets if you want to see some samples of similar work. I bought bullets from him before, and he does beautiful work.
Greg

Avery Arms
03-17-2009, 12:36 PM
Before the business went belly up Don at Groove bullets was making CNC solid brass HP bullets and people were having great luck with them on targets and game alike.

Cost is the kicker, free machining leaded brass round stock isn't cheap and neither are the machines that are able to kick out bullets at any reasonable speed. Back then Don was charging a bit over a dollar a bullet, everything was backordered and he was still barely breaking even in spite of doing a great deal of the labor and marketing himself.

Somewhere I have two of each size he made, I was a moderator on that forum back then and got free bullets every so often:D


PP

JIMinPHX
03-17-2009, 04:23 PM
A friend of mine was one of the people who cast the bronze lamp posts that are in Bryant Park NYC. I refuse to believe that she can do anything that I can't do, aside from childbirth & looking good in a skirt. ;-)

I'm sure that casting bronze is not as easy as casting lead, but I'm also sure that it's not impossible. My real concern would be chamber pressure. I would expect that a bronze boolit, being harder than lead alloys, would create a MUCH higher chamber pressure with a normal powder charge. Since I don't have pressure testing equipment, that would stop me from trying it.

Old Ironsights
03-17-2009, 05:02 PM
I keep saying that anybody with access to a Davenport Screw Machine can write their own ticket in Cali...

trevj
03-17-2009, 05:59 PM
You need a screw machine or a CNC lathe with a feeder (probably easier and cheaper to get running these days) and you need a couple special tools. A rotary broach would clean out the holes to whatever shape you wanted (hex, square, octagonal, splined, etc.) , then use a roller swage on the machine to roll over the noses to the ogive shape required, and you'd be in direct competition with Barnes.

Should be able to run a cycle time of about 15 or 20 seconds per bullet...at low rent kind of speeds and feeds, and definitely at low rent cost of admission to the game, at least relatively.

With the rollback in the overall economy that we keep hearing about, it seems only a matter of time before a lot of decent older CNC machines start reaching the market.

Cheers
Trev

docone31
03-17-2009, 06:30 PM
On the casting side, a wax could be made up, sprued and invested. Probably several hundred at a time. They could be seperated and shot polished. Sizing would have to be calculated prior to casting.
It could be done.
Pressure would be an issue, so would be wear in the bore.
It could be done though.

troy_mclure
03-17-2009, 09:20 PM
OK, so cast bronze is out! lol
the guy may have been mistaken, or just outright lied.

Greg5278
03-17-2009, 09:29 PM
The casting idea is our for ease of production. If you are worried about pressure, you lessen the bore conatct area. I designed a brass solid for the 12ga shotgun, after firing some poorly designes solids by Bridger bullets. The shank Diameter was not undercut to less than land dimension. The pressure was excessive on normally mild loads. I changed the design to 4-.060" wide driving bands. The results were excellent, the pressure went away, and the bore was much cleaner. The same concept is needed if trying to cast Zinc solids. I manged to cast 690grain Zinc solids in my big 1043gr mold. The slugs are hard, and can be fired as cast. They will not expand.
Greg

docone31
03-17-2009, 09:38 PM
Well, the main point is, sooner or later, we will do it!
With enough experimentation, a replacement can be found. It will be a question of design.

z4lunch
03-17-2009, 11:21 PM
I would like try to make machined bullets on the lathe just because I can...
As per a few of the posts. My concern would be excessive pressure first and how to eliminate that, and repeatability second
Steve

Shiloh
03-18-2009, 12:17 AM
I saw some home brew machine made .30 cals.turned from hard brass rods. Well made bullets. They had a lead core for added weight, a concave base, and driving bands cut into the slugs like the Barnes solids. From a .30-06 they would go through good size oak logs.

Shiloh

Willbird
03-18-2009, 08:39 AM
Many of the barnes bullets are swaged I think, and they are more of a copper alloy than bronze typically. One of the barrel makers(I think it was Lilja) says that lathe turned bronze bullets actually wear a rifle barrel at a faster rate via friction than the throat erosion, hence a chrome moly barrel may wear longer than a stainless one using these bullets.

Bill

13Echo
03-18-2009, 09:21 AM
The original high velocity, spitzer bullet was a solid bronze bullet used in the French 8mm Lebel.

Nothing new under the sun.

Jerry Liles

felix
03-18-2009, 09:49 AM
Bill, actually its the manganese constituent that lends the ability of "iron" to withstand shear, and most versions of "stainless" do not have manganese to any amount to speak of. Also note that bronze is actually a copper based metal like steel is an iron based metal. Brass is a subset of bronze, in that the only "impurity" within the copper is zinc. So, when someone says bronze it actually could be brass. ... felix

Now the real trick is getting iron and copper together into a composite metal. That patent was granted to the Mehenite (sp) corporation, and the metal had that corporation's name as the name of the alloy for some time. Other metal manufacturers now make it and as we know that material, in general, makes the best boolit molds to date. ... felix

Cap'n Morgan
03-18-2009, 11:19 AM
I would like try to make machined bullets on the lathe just because I can...
As per a few of the posts. My concern would be excessive pressure first and how to eliminate that, and repeatability second
Steve


One efficient way of controlling the pressure when dealing with solids, is to reduce the area in contact with the rifling. Unlike a cast lead boolit where you need all the shearing strength you can get, copper and brass bullets has actually too much of it.

http://lh3.ggpht.com/_H70RUN_TQNw/ScEIocRAWjI/AAAAAAAAAEs/6dETkzZJheI/IMG_0647.JPG


Only the narrow guiding bands on this 107 grains .277 bullet are full bore diameter, and the diameter between the bands are smaller than the land diameter - leaving room for any material sheared by the rifling.

Willbird
03-18-2009, 01:23 PM
Bill, actually its the manganese constituent that lends the ability of "iron" to withstand shear, and most versions of "stainless" do not have manganese to any amount to speak of. Also note that bronze is actually a copper based metal like steel is an iron based metal. Brass is a subset of bronze, in that the only "impurity" within the copper is zinc. So, when someone says bronze it actually could be brass. ... felix

Now the real trick is getting iron and copper together into a composite metal. That patent was granted to the Mehenite (sp) corporation, and the metal had that corporation's name as the name of the alloy for some time. Other metal manufacturers now make it and as we know that material, in general, makes the best boolit molds to date. ... felix

Meehanite looks and machines like soft cast iron. According to their webpage they have many different compositions for different purposes. The stuff I machined was designed for dimensional stability because it was used for "tombstones" which are a device used in a horizontal machining center to fasten multiple fixtures to. It machined sort of like cast iron but it was a bit softer, old texts say to use lard as a lubricant for tapping. The only peculiar thing about machining it was that it was difficult to get a tap STARTED....the tap had a tendency to just ream a taper hole rather than grab ahold and tap the threads, the solution was to use a rigid tap holder that had no float.

Bill

Alasgun
03-18-2009, 01:43 PM
All this talk of cast / machined bronze bullets takes me back a ways. I was making some large compressor parts a number of years ago out of a material called Bearium metal. It was immediatly obvious to me "this is great bullet material". The composition is 70%copper,26%lead,4%tin. This was right at the time the Barnes folks were developing their first all copper bullets and then as now the major complaint was the extreme length needed to have any weight.
Those Bearium bullets helped solve that problem along with the fouling problems as well.
I recently checked and the company is still around, a net search for "Bearium Metal" will get you to a home page, all the little symbols at the heading are companys they now own, go to the extreme right and click on the Bearium symbol and your there.
Your bullets will have to be machined and they will be expensive ($30 per foot for 1/2 dia stock) but what the heck, you will be in an exclusive club! I still have the samples I submited to Art Alphin at A-Square and J.D Jones for testing. Both sent me back nice letters and J.D sent back the FIRED bullets. In a time when the big boys were flooding us with copper this and that, I didn't have a chance at commercializing my little experiment.
Mike

joeb33050
03-19-2009, 02:45 AM
Bill, actually its the manganese constituent that lends the ability of "iron" to withstand shear, and most versions of "stainless" do not have manganese to any amount to speak of. Also note that bronze is actually a copper based metal like steel is an iron based metal. Brass is a subset of bronze, in that the only "impurity" within the copper is zinc. So, when someone says bronze it actually could be brass. ... felix
BRASS is a copper and zinc alloy, generally.
BRONZE is a copper and tin alloy, generally.
There are variations, aluminum bronze, arsenic bronze, etc.
Brass and bronze are very different, mariers love bronze, hate brass.
Sintered metal bronze bullets would be very handy, also sintered lead bullets. Powder metallurgy could give us oil impregnated bullets, maybe even cheap.
joe b.
Now the real trick is getting iron and copper together into a composite metal. That patent was granted to the Mehenite (sp) corporation, and the metal had that corporation's name as the name of the alloy for some time. Other metal manufacturers now make it and as we know that material, in general, makes the best boolit molds to date. ... felix
Sintered!!!

rhead
03-19-2009, 05:04 AM
The bronze bullet would also be quite a bit lighter than a lead bullet of the same size. That would reduce the operating pressure I have no way of telling if it would completely offset the increased resistance to engraving. Reduce the thickness of the driving bands and that will help.

sheepdog
03-19-2009, 12:23 PM
I hate to be the bearer of bad news but..

++++++++++++++++++++++++++++++++++++++
The definition of ap ammo is at 18 USC 921(a)(17):
"(B) The term `armor piercing ammunition' means-

(i) a projectile or projectile core which may be used in a handgun and
which is constructed entirely (excluding the presence of traces of other
substances) from one or a combination of tungsten alloys, steel, iron, brass,
bronze, beryllium copper, or depleted uranium; or

After far as I know making these is a big no no. Even if you don't plan to sell or distribute. If you're going to do this that's your business but don't go advertising it.

Greg5278
03-19-2009, 02:34 PM
The way to keep it Legal, is don't use it in a handgun! Rifle sand shotguns are exempt.
If you check the Website for Lehigh bullets, they give the same disclaimer, bullets can only be used in a Rifle. The copper bullets are niot subject to that regulation, hence the DPX handgun bullets. Brass cannot be used in the Handguns or it would be considered "armor Piercing".
Greg

deltaenterprizes
09-30-2009, 10:30 AM
Bronze pistol bullets are illegal as defined in the federal "Armor Piercing Ammo" passed in the mid 1980s

WickedGoodOutdoors
09-30-2009, 11:21 AM
Here is the idea. I dont have the tools to do it.

Take a 9mm Brass case 9.96 mm (0.392 in) and Swag it down hydralically over a length of steel drill rod #31 .120 3.048 Diameter

the end product will be right at .308 and can be used in a .30-06 gun

the steel point can be blunt or sharpened to a needle point. The 9mm brass case will be a gas check self lube sabot that will travel with the steel until the steel sheds it upon impact.

Bet it would be wicked fast and cheap to make using surplus.

OK So if anybody makes a million dollars on my idea ;Just like Optigrabs, you have to share it with me.

Capt Walt


"Hey Those Cans are Defective"!

http://cdn.videogum.com/img/thumbnails/photos/friday_fight_100_movies/the_jerk.jpg

leftiye
09-30-2009, 12:11 PM
Before Barnes made their X boolits they experimented with a lot of other designs. One of those (waaay before copper) was a machined brass design. The reason that I mention it was that it was brass bore rider (IIRC) with copper driving band. Bronze that I am famiiar with is both too hard and too brittle to be any good for bullets. But you could solve the pressure problems with a copper driving band bore rider.

leftiye
09-30-2009, 12:18 PM
As for armor pierceing bullets. Criminals (convicted) already are "not allowed" to have guns anyway. Hasn't stopped them yet.... Another intelligent tour de force by our lawmakers...