Powder Coating

Stuff gleamed from other sites

teps-
0: Normalize at 400 *f (204 *c) for 1 hour then quench if desired for harder bullets.
1: Thoroughly dry bullets. Clean from any residue and do a quick sort for defects & sprue, etc. Bullets must be DRY. HP bullets tend to hold moisture in the cavity.
2: Tumble or swirl bullets in powder coat until static causes them to be thoroughly and evenly coated. 10-20 minutes. HP bullets may require more tumbling to even out the powder in the cavities.
3: Sift the bullets from the excess powder.
4: Spread bullets onto baking mesh tray over cookie sheet. Bullets may be piled, but single layer is preferred. Try to avoid flat base to base contact. It is better to spread the bullets with a hard tool such as a spatula than your fingers. This seems to disturb the powder coating less.
5: Preheat oven to 400*F/ 204*C. Bake for 10 minutes.
6: Promptly remove the bullets and transfer them to another container. Be sure to break up any clumps while warm and stir them about. A plastic spatula or rounded wooden stick may be helpful.
7: Size if needed.
Supplies:
1: vibratory tumbler or plastic tub (i.e. cool whip). Should have lid to contain dust.
2: Toaster oven capable of a consistent 400 F* ($10 or less at thrift stores)
3: Some hardware cloth or a mesh pizza tray for baking. The latter is cheaper.
4: A rimmed cookie sheet to place under the mesh baking tray when you pour out bullets.
5: Gloves that can handle heat. Mark them “Lead Only.”
6: Powder Coat. I suggest 400 degree polyurethane. **
** Avoid Harbor Freight powder. Their black powder is reported to have abrasive qualities. Do not use it. Also their colored powders do not coat as evenly as other brand
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From another site

Coating primer..

Bullets contact the bore and interact with heat and pressure from the powder gasses. Bare lead will smear onto the bore and quickly cause leading problems. Pure lead is so soft that powerful loads may turn the rifling into a rotary rasp which simply shaves the bullet rather than engrave rotate it. So it has always been necessary to either clean the bore constantly or protect it from leading. (& still is with other metal fouling.)

I will address alternative solutions to this problem in semi-historical order, then poly coat in it's own section.

1. Bare Lead- Black powder often just uses bare soft lead and a lot of cleaning time. The lead has to be very soft to engrave well and ensure consistent pressures.
2. Patching- Black powder shooters discovered quite early that having a bit of paper, cloth, or leather wrapped around the bullet helped with engraving and greatly reduced leading. This is improved if the paper is greased with some kind of oil or wax.
(3.) Harder Alloys- (in parentheses because alloy strength is relevant to all other methods and is still used. It was used alone too.) Increasing the tin and antimony in the lead alloy increased hardness and strength. Bullets with a bit of antimony in them can also be heat treated for increased hardness and strength.This solves the rasp problem up to a point. However, those metals are more costly. Also it is desirable to tune the hardness of the bullet to the desired expansion in it's intended target. If the game should have a soft bullet, it will perform worse if the gun needs a hard one. Thus compromise happens.

Lead hardness has a very direct relationship to lead strength in terms of tensile and compressive strength, and ductility. Therefore it is common proctice to talk about lead hardness when lead strength is really what matters for a particular issue. Compressive strength and ductility are critically important for accurate bullets. (Many reloaders pass on the old bad info about hardness relating to velocity. Nope- it relates to pressure which tends to go up with velocity. The difference matters. Lyman still publishes load data based off of this misconception.) A bullet is squashed under pressure and acceleration and expands. Typically it is also larger than both the bore and the rifling. Best practice for lead is to size bullets to be .002" =/- .001" over the size of the groove diameter. Proper sizing ensures good engraving with a full bite. It also reduces leading. This is counter intuitive because one would think squeezing lead through a smaller hole would cause more to rub off. Rubbing does lead to leading, but very little. The primary leading mechanism is gas cutting. Gas that can slip in between the back end of an undersized bullet and the small gap between the land and the groove works like a cutting torch and vaporizes lead. This vaporized lead deposits onto the bore rapidly.

Here's where strength comes into it. If you take two bullets correctly sized one being soft and weak, the other being hard and strong. The soft one will lead very slightly more than the strong one. Not enough to make a difference. So one would think it doesn't matter as long as the sizing is right. It does though. Suppose you make bullets of the same diameter, correct to the bore, such that your bullets all have equal pressure from powder, but you have made lots of bullets in progressively harder(stronger) batches. If you test each bullet for accuracy starting from soft to hard you would find that the group size progressively decrease as hardness and strength increases. Simply put the bullet gets distorted under the squishing and is less uniform in flight. But wait, there's more. There is a delta point where increased hardness results in worse groups. The reason is that you want the bullet to swage to the barrel- it needs to be squishy enough to take the shape of the barrel and a good engraving. But it needs to be strong enough that the portion of the bullet not engraved will spring back to original shape. So an ideal bullet for the gun will have a strength such that it's compressive limit of ductility is ~10% lower than the peak pressure of the powder charge. Whether this hardness is desirable for expansion on target is another thing. Compromise, or differential temper, or differential alloy are ways to address this. Typically the critter wants a soft bullet and the gun wants a hard one.
4. Wax/grease based conventional lubing: ~1850s to present~ The most popular solution for lead bullets is to coat them entirely, or in special grooves with some form of lubricant. These lubricants prevent lead from sticking to the bore and reduce, but don't eliminate leading. Various methods such as pan lubing, or application with a luber-sizer machine one at a time are used. Ultimately they work pretty well if the lead hardness is up to spec, and the size is chosen correctly. Bullets encounter a lot of heat from friction, particularly rifle bullets. Thus there must be enough lube of a correct composition to deal with that friction. In most cases this creates a practical velocity limit around 2200 FPS. Some people manage to get above that, but most do not. This limits the type of cartridge that runs well with cast lead bullets. Most modern cartridges are designed around higher pressure and velocity than cast lead conventionally lubed can handle. So modern cartridges with powerful flat trajectories must be down loaded to work well with lead bullets. The bullet isn't strong enough, and the lube can't keep up.

These forms of lubrication are messy and labor intensive. The tools used typically cost near $200, and multiple sizing dies will be required.

** Tumble lubing. In the 1970s or 1980s, Lee began to sell a tumble lubing system. This is very labor efficient and works well if done properly but has some drawbacks. It is very inexpensive too. Bascially a pile of bullets are put into a container with semi-liquid lubricant and shaken or swirled untill they are all evenly coated. Then this is allowed to dry, typically 24-72 hrs. Usually two light coats works best, with a full cure in between.
The drawbacks of Lee Liquid Alox are: 1) misapplication. Many people used to conventional lube put it on too thick, on the theory that mores must be better. This makes for sticky bullets that smoke a lot when fired. It also means they are unlikely to dry well, which means the lube won't protect the bore as well. Particularly if it gets scraped completely off during the reloading stage. 2) The lube itself has upper limits of velocity where it works well. 1700-2000 FPS depending on technique. 3) It can become sticky in hot wether and attract abrasive dust. 4) fake reasons. There are a bunch of people who did it wrong and thus dismiss the whole system. I can personally attest that it works just fine if you do it right.

Some people tumble on other things like floor polish, or custom formulas.

The superior variant of tumble lubing is Recluse's 45/45/10 This uses half liquid alox, half Johnson's Paste Wax, and then is made thin with a little mineral spirits. (White Label Lube sells this, and also the ingredients even cheaper than Lee http://lsstuff.com/store/index.php?main ... ucts_id=31) This is dirt cheap, and works brilliantly. Most people report it works up to about 2500 FPS if you do two light coats. Some get as high as 2700 FPS without leading. Thinner is better, and I find it works best with warm bullets. I dry my bullets in a toaster oven, so this is no extra work to simply tumble them right after I pull them out. It dries hard and not sticky. It won't get sticky in hot weather or attact dust. If you keep it thin, it won't smoke. Leading is virtually eliminated. (same sizing and hardness requirements apply)- As with all tumble methods, you do have to clean your seating dies in between sessions or a gradual buildup of lube will throw off your settings.

It takes me about minutes of work to tumble 4-1200 bullets. I like to cure them overnight in an oven at low to speed the process.

If all you ever shoot is standard pressure pistol cartridges outdoors, this will meet your needs perfectly.

6:paper Patch- ~Circa 1900~ As metallic cartridges took over and powder pressures increased dramatically, soft lead wasn't strong enough to do the job. Random patching was not consistent enough and could interfere with chambering tolerances. Machining was getting better, and there was a general desire to decrease tolerances and have tighter fit for better long range accuracy. One effective solution was to systematically make special high quality treated paper in precisely measured patches and wrap the bullet with them before it is loaded into the metalic cartridges. Early smokeless military guns have been loaded this way including 30-06 and 30-40 krag. It actually works very well and is still used by some PALMA shooters at 1000 yards. Interestingly, the paper is adequate to protect the lead bullet from the heat of the powder gasses. Recovered bullets are often extracted from targets with the paper on the base of the bullet intact. It also allowed for new bullet shapes optimized for aerodynamics rather than for carrying lubricants. Enter the modern spitzer profiles.

These are labor intensive to create and difficult to do uniformly. Paper which sticks out of the cartridge may cause problems with bunching up, so bores need to allow clearance. The paper sticking out is vulnerable to damage which may interfere with performance or even cause a failure to load fully. Not good for military, and not ideal for the rest of us either.

7: Partial and Full Metal Jacket/ Half Jackets/ Gas Checks/ solid copper- ~1900 to present~ As machine guns came onto the scene, inconsistencies in paper and very hot barrels proved that conventional grease lubes and paper patches were inadequate for military firearms. A little bit of bad lube, or soft alloy would almost instantly clog up a machine gun barrel with lead fouling. Also bullets shouldn't be fully coated in lube so dirt doesn't stick to them. Pretty much every type of firearm in military service could now be expected to fire hundreds of rounds or thousands in a single engagement with no opportunity to clean the lead out. This means a little bit of bare lead outside of the metallic cartridge will come into contact with the bore. So any flaws in quality control with the bullet would also amplify the problem. Barrels could also get hot enough to actually melt some of the bullet that was touching them. The solution was to replace the paper patch with a patch of metal which was harder than lead, slippery, and stronger than lead. Alloys have changed, but the principle is more or less the ame.. This solves many problems. It is also costly. The trade offs are material cost, and often inferior expansion on impact. (Silly treaties about military ammo were signed in this era by people who did not understand terminal ballistics. Modern military ammo is handicapped by these treaties. In effect the treaties do not change the result, they just require a bigger bullet to do the same job or a faster bullet to do the same job. There is no nice way to kill a person.)

I'll assume that you are very familiar with modern jacketed ammo. It's good. This discussion just wants to remind you that it is a response to several considerations and has to trade off some things to achieve others. Chiefly, cost, availability, total projectile density, complexity of manufacture, and often poorer terminal performance compared to tuned lead alloy. Fancy premium hunting bullets are really good at getting the bullet precisely to the game a long way off. In many ways they aren't as good as old fashioned lead when they get there. The difference in premium ammo is often a lot of engineering to make a multicomponent bullet behave like a solid one with the right amount of squishiness and mass.

This just touches on the considerations for jacketed ammo, since the article is about cast or swaged lead bullets, and powder coating.

The main reasons people are using those is cost, and also component availability
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Powder Coat Howto (Shake and Bake)

Powder purchased from emeraldcoatings.com

Powders come in 2 types, tgic and tgic free

Tgic is considered toxic (please read report and use at your own risk)

I try to purchase tgic free, but i have tried tgic powders and they tend to give better results. The exception to this is tool blue.

The powders that I have test and work for me.

1. Tool Blue (tgic free)
2. Traffic Red (tgic)
3. Yellow Green (tgic)
4. Sapphire Blue (tgic )

CHECK WITH EMERALD WHEN YOU BUY, 3 &4 in the list used to show as tgic-free, now shows tgic on their site.
Equipment required.

1. Cheap toaster oven and oven gloves ($20 - $40)
2. Non stick tray or non stick parchment paper/foil
3. Tea spoon
4. Plastic/latex gloves
5. Plastic number 5 container, number underside of container.

Method

1. Place 50 bullets 9mm in food container.
2. 1 tea spoon of powder (50gr weight)
3. Shake in food container for 60 seconds, swirling motion.
4. Take the coated bullets out of container (I put some powder on my gloves and pick out bullets from container) and place on non stick tray.
5. Bake according to manufactures recommendations, 375F/10M for sapphire blue
6. Leave to cool for 30 min

I find that the higher the humidity the less likely the powder will stick with this method,

All baking was outside, Never use toaster oven for food after powder coating.

All powders are bad for you if inhaled or ingested, only bake outside.



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The main advantage for me with pc bullets is no leading, cleaner shooting (not lube to burn off), and loaded to jacket bullets speeds.

The bullets are sized using lee push through sizer, .356 in this case.

Some other bullets I have powder coated.

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The url has more info.
http://castboolits.gunloads.com/showthread.php?273585-How-fast-can-you-push-a-powder-coated-bullet

I have some 160gr 308 I will try at jacket speeds some time next week and let you know. I don't think leading will be issue it's finding accurate load. I use WW only and have read on some forums of people using pure lead with Pc.

My goto powder is tool blue which gives best coating for tgic free powder.

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tootall said:
Great thread!
I am looking into PC

Realistically, if I use WW lead with both PC and gas checks, what velocity could I get?
Could I duplicate a .30-06 M1 load? (~2700 fps)
http://www.loaddata.com/members/search_detail.cfm?MetallicID=2713

What powders are most suited to PC?
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These were done with a single coat of Phantom Glass Black from Emerald Coatings.

PHANTOM GLASS BLACK POLYESTER POWDER (new style mirror black)

* GLOSS LEVEL = 80 -90% ON 60 DEGREE METER

* CURE SCHEDULE = 400F/10 MIN or 375/15min @ PMT HARDNESS= H-2H IMPACT RESISTANCE: UP TO 80 IN/LB

* RECOMMENDED MIL THICKNESS = 1.50 – 3.50 MILS CROSS HATCH: 100%

* SALT SPRAY RESULTS = 1000+ HOURS

TGIC free? Doesn't say. I'll try to find out

Auggie D.
 
A few bullets I've powder coated so far this week,around 500 for a couple hours work. I only have a few colors to work with right now.HF Yellow,Red an White and some dark green. I played around with the yellow and red mix to get some brown and burnt orange colors, a mixed the green 3:1 with white gives the appearance of speckle tone green. I kinda like that color so I'll probably stick with that for future use. I have some bright yellow,orange and zombie green coming soon.
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To coat my bullets I use a Utter Butter hand cream container,I fill it about half full of various color plastic hair beads,to the beads I add a half teaspoon of color and 50 rifle or pistol bullets,screw the cap on tight and place it on my small rock tumbler and just let it roll for about 15 Min. while the toaster oven heats up. I pick the bullet out of the mix with a large pair of tweezers and place them on a sheet of non stick foil pop them in the oven for 20 min. at 400 degrees while I let another batch tumble and get coated up. I can coat about 100 bullet before having to add another batch of powder. After they cool I size accordingly and apply gas checks were needed.
 
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Figured I'd post this even though there are a few others like it. More evidence for the non-belivers ;)

.359" 150gr cast, powder coated with signal red using the dry tumble method and baked in a toaster oven. Finished diameter of .362" to .363". Fired from an Enfield No.2 revolver, .38 S&W. Didn't chrony but not a high-velocity cartridge.
Recovered 3 from the berm.




Only places the powder coating is missing is where the lead was gouged or scraped from hitting rocks, sand, and dirt.
 
I am going to order up some powder and give this a try on some 9mm and .38 Special. I am planning on ordering from Emerald coatings and, from what I have read, tool blue seems to be the colour to go with. How many bullets would you say you can coat with 1lb of powder? Of coarse, shipping is cheaper the more you order. I have also read guys are using Lee push through sizers. I have a Lyman lube sizer and was hoping to use that. Some have been modifying them to work as push through sizers but I am wondering if it will work well in its original configuration sans lube of coarse.
 
OverUnder725 said:
I am going to order up some powder and give this a try on some 9mm and .38 Special. I am planning on ordering from Emerald coatings and, from what I have read, tool blue seems to be the colour to go with. How many bullets would you say you can coat with 1lb of powder? Of coarse, shipping is cheaper the more you order. I have also read guys are using Lee push through sizers. I have a Lyman lube sizer and was hoping to use that. Some have been modifying them to work as push through sizers but I am wondering if it will work well in its original configuration sans lube of coarse.
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i've read up words of several thousand per pound but i seem to waste a lot, though i haven't gone through a pound yet. Yes tool blue and Kawasaki green are great colours for tumble coating. i use the Lee push through sizers but have used my lyman 4500 with no lube in it without issue other then a bit of paint build up from excessive flashing during the baking process.
 
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