DIY Smokeless Powder - No. 7 Smokeless Powder Manufacturing

[deces]

Following.

[MisterStyx]

So, I'm familiar with this book, and I asked a chemist on the mewe primer chat about these recipes and they seemed very wary of kicking out toxic fumes every time you fired a round.

Glad someone is trying it though. I'm just a little afraid to.

[MUSTANG]

So, I'm familiar with this book, and I asked a chemist on the mewe primer chat about these recipes and they seemed very wary of kicking out toxic fumes every time you fired a round.

Glad someone is trying it though. I'm just a little afraid to.

I am not poo poo ing the comment on Toxicity of any/all of the chemicals used; but has anyone taken the time to read the MSDS (Manufacturing Safety Data Sheets) on any of the day to day items found under your kitchen and bathroom sinks? Has anyone noticed the proliferation of "California Hazard Warnings" on the daily products we buy? 99.9999% of those active on this and other similar firearm related sites are "EXPOSED TO LEAD"; ohhhhh my Goodnessssss - we are all going to die! ; Wait a minute; with the exception of Enoch and Elijah in the Old Testament - those before us, those with us, and those coming after us - WE ARE ALL GOING TO DIE. My goal is to put off that inevitability - but do so without making life miserable an not worth living.

Wearing gloves, wearing a mask where chemical dust in the air or particulates created while working with the products could occur, or breathing in the vapors of some of the Primer or Powder chemicals/processes should be judicially considered and controls be utilized while pursuing the Primer and Powder production processes discussed across numerous threads on this site.

I am gearing up to resume the experiments on this thread and others; which is why I am responding to MisterStyx observations. My current thinking is that the chemicals, the ratios, etc... are not significant areas of exploring minor changes. The processes are areas I believe significant exploration and refinement of those processes can provide improved results. I have noted that the No.7 powder if it is too fine does not seem to perform as well. My current speculation is that a larger grain structure than finally ground is required to get a good burn and pressure inside of a brass case - but then Too Large a Grain structure would also be problematic. That "Sweet Spot Zone" is what I will be seeing to learn in the near term. It is interesting to note that in the Original Authors writings they speak to screening out the very fine mesh product and putting that back into future mixes; so the production of the No.7 powder does not destroy or transmute the powder mixture to where the "Fines" are no longer useful in reprocessing with a new batch.

To me it seems that we "Re-Learn" what previous generations knew. In m case; I recently bought an original Hard Copy of "Hatchers Notebook" by MGen Julian S. Hatcher Retired. Reading from the book this morning; I found the following on page 305:


Click on Image to enlarge and read text.

Although the page is dealing with "Black Powder"; the grain structure analysis still applies.

I'll post again in the near future when I have more to share.

[barnetmill]

the grain structure

If we are talking smokeless powder, tiny particles in residues from smokeless powders can sometimes upon loading into a cartridge, will exhibit extremely high pressures. In chemistry, the greater the reactive surface area per a mass, the faster the reaction.
But there can be obviously be lot more to the story.

[MUSTANG]

Back to the range yesterday. Shot 10 rounds of No.7 mixture. First Five rounds was a batch made from scratch with new materials. Second string of five rounds was from a batch made using a previously manufactured lot of No.7 powder that had been ground very fine; that batch had multiple failure to fires. This second batch was mixed with an equal volume of water; dehydrated, and remanufactured to establish "Re-Use" of scrap from making No.7 Powder was viable. The 10 rounds as described above all grouped into a 4 inch circular group at 100 yards.

The principle objective was to determine:
(a) Does a larger grain structure provide a greater ignition reliability?
(b) Is reconstituting old finely ground powder; and processing to larger grains viable.
Answers to both (a) and (b) seems to be yes.

My LabRadar continues to not pickup shots in these tests. Snow accumulation in front of Firing Line prohibits my ability to set up a Sky Screen type Chronograph; so velocities will have to wait a few weeks until Spring Thaw completes. Although far from scientific and quantitative; Shot sound reports and my perception of felt recoil places these 10 rounds in the same category as using the .308 RCBS 200 Sil boolit with 30 Grains of BLC-2 and a dacron filler in my Remington 700 chambered for .308 Winchester.

These ten rounds used powder coated Lyman 311644 boolits weighing 198 Grains. One objective was to see if Increasing boolit weight started to have any affects with No.7 powder. The powder charge remained at 33 Grains. One area of interest was if there would be any signs of a potential “Pressure Spike” due to an increased wright of boolit used. That does not seem to be the case based on spent primer analysis as no indications of flattened or backed out primers is visible.


click on the attachment to enlarge and view primers more closely.

Once again; the No.7 Powder formulation used:

Potassium Nitrate KNO3 2.1 grams or 32.4 grains
Ammonium Nitrate NH4NO3 7.14 grams or 110.2 grains
Willow Charcoal C 2.10 grams or 32.4 grains
Lead Nitrate Pb(NO3)2 1.720 grams or 26.54 grains

And, the specification on the Rifle and Load Data:

Rifle: Remington 700 ADL Varmint .308
Barrel Twist: 1 in 12
Boolit: 311644; Actual weight 198 Grains
Ballistic Coefficient: 0.272
Brinell Hardness: 20
Bullet sized: .308
Alloy: 96% Lead, 3% Antimony, 1% Tin
Bullet Lube: Eastwood Green Powder Coat
Gas Check: .014 Ameri-max Aluminum
Powder: No.7 Home Made Smokeless Powder
Primer: Federal Large Rifle 210
Case: Mixed commercial Brass
OAL: 2.800 inches
Distance: 100 Yards.

In this test sequence; both powder tests were liquified in water (equal volume of water to volume of chemicals used). The mixture was poured onto a glass pie plate and placed into an electric dehydrator with a temperature set at 125 degrees Fahrenheit. The mixtures were allowed to dehydrate the water out for a period of 24 hours on the timer. (Note: These test mixtures were NOT cooked over the stove - Dehydration at 125 degrees only).

I did not screen the very Fines out after grinding each mixture for the No.7 powders, but grain size was reduced by grinding the broken cake until all particles fell through the large kitchen strainer I have been using. In future testing; I will continue to use the Large Kitchen Strainer to get a Maximum size in the No.7 powder; but I intend to also use a 20 Mesh screen in next testing to ensure a Minimum size is established. This should narrow the window and provide a more consistent “Air Space” between particles in the No.7 powder when loaded.

[MUSTANG]

Follow on to previous post. The No.7 Powder might be described as one of the Transition Powders between the Black Powder era and the Nitrocellulose based Smokeless Powders of today. With that come many comments, observations, questions concerning fouling. Thought I would post a picture of the Rem 700 Barrel Crown area as a depiction of the level of powder fouling from 10 rounds that burned fully in the test reported in post #85 above.


click on image to enlarge

[MUSTANG]

For the next test firing session; the granulation of powder will be evaluated. The No.7 Powder mixture was created with an equal volume of water to chemicals in the mixture; thoroughly stirred to mix well. The wet mixture was then dehydrated in an electric dehydrator for 24 hours at 125 degrees Fahrenheit on a glass pie plate. The mixture when dried formed a very thin hard cake with the bottom being totally black from the Charcoal; and the top being a light gray color from some of the chemicals either separating to the top – or through evaporation pulling some of the chemicals to the top.

The cake was scrapped/broken loose from the Glass Pie pan by use of a razor blade scraper. The resultant chunks and scrapings were transferred to a small stainless steel bowl. I use the face of a small hammer from Harbor freight as the pestel to grind (not hammer) the particles until they are able to be screened.





For this test cycle; the following screening of the powder kernels was performed.

All powder was screened through an old hand held Kitchen screen; I estimate it to be about 10 to 15 Mesh. Any particles not passing through the screen were ground again until they passed the first screen.

5 Test rounds were prepared from the 1st screening powder. The powder for this test would pass through the 10 to 15 mesh hand held screen; but would NOT pass through a 20 Mesh screen. When loading 33 Grains of this Mesh No.7 Powder, the kernels were visibly large compared to other screen sizes. Charging the powder in the case required individual operation using a funnel, a chop stick to slightly push the powder into the case, and then tapping numerous times on the side of the case to cause the powder to drop fully into the case and settle to where it was about at the level of the case neck.

An additional 5 Test rounds were prepared from the 2nd screening powder. This powder passed through a 20 Mesh screen; but would NOT pass through a 40 Mesh screen. Although it flows easier into the case compared to the larger kernels in the previous description above; these also required a chop stick to slightly push the powder in the funnel down into the neck, and then tapping on the case with a spoon to settle the powder – once again about at the neck are of the case.

The final powder that passed through the 40 Mesh screen was stored separately in it’s own plastic jar formerly containing Vitamin. I anticipate this lot f powder will not be tested, rather it will be returned to the next mix for recycling into future No.7 Powder manufacturing depending on results of the previous two lots of 5 Test Rounds.

These two lots of Test Rounds will be fired some time in the next two to three weeks. Forecasts call for 4 to 6 inches of snow Thursday through Monday; and I want to get velocities with a SunScreen Chronograph on these rounds if possible. Currently existing snow at the range keeps me from setting up the Chronograph; so until we get enough melt off I will be on hold for Testing these two lots.

[MUSTANG]

Cabin fever day; so my wife suggested we go to the Rifle Range. The forecast storm front had not materialized when we departed the house this morning; but was beginning to make itself felt at the Range with 33 degrees Fahrenheit temps, and 35 to 40 mile an hour winds. Slight snowfall from last night was becoming airborne and blowing across the Rifle Range off and on from the wind. Because of the gusting winds; I decided against putting up the Chronographs as I could see them being blown over, or the Sunscreens being blown away. I fired two strings of 5 rounds each with the No.7 powder today. Rifle was a Remington 700 with 26inch Heavy Barrel, chambered in .308 Winchester. Boolit used was an NOE 311041 weighing 182 grains when powder coated with .014 Amerimax Aluminum Gas Check.

String #1 was with the powder screened by falling through a 10 Mesh kitchen sifter (estimated size); but being captured on a 20 Mesh screen. A charge of 33 Grains in each round. This was the coarsest grain structure tested. I was not shooting for accuracy development, rather for determining reliable ignition and consistency. Group measured 4 and 1/8 Inches.




String #2 was with the powder screened by falling through a 20 Mesh Screen; but being captured on a 40 Mesh screen. A charge of 33 Grains in each round. This was a finer grain structure, but it also had about 30% to 50% of the “Fines” falling through the 40 Mesh screen and the fines were collected and stored elsewhere. I was not shooting for accuracy development, rather for determining reliable ignition and consistency. Group measured 1 and 1/8 Inches. I called one of the shots as “Wild” based on the blowing snow obscuring the Target as I was shooting that round. It landed 8 inches out of the group.




The 20 to 40 mesh screened powder actually performed significantly better in todays limited test firing. It would have been nice to capture the velocities and deviation for the tests today; but weather did not cooperate unfortunately. Will do similar test again in near future. If the 20 to 40 mesh screening should show a better grouping once again; we might be on to better information concerning optimum granule size for this powder.

[MUSTANG]

Thought some might be interested on seeing a Materials Cost analysis for the No.7 Powder.

Computing cost per pound of No.7 Powder (Shipping Not included in this computation):

Chemical cost per pound:

Ammonium Nitrate - $5.00 https://www.ammoniumnitrateforsale.com

Potassium Nitrate - $4.80 https://www.ammoniumnitrateforsale.com

Lead Nitrate - $35.00 https://www.laballey.com

Charcoal - $8.32 /Free https://www.ammoniumnitrateforsale.com


Cost per pound to make one pound of No.7 Semi-Smokeless Powder based on above sources is $9.66 if it is made from purchased Charcoal. Compare that to my paying $38.99 for one pound of BLC-2 Smokeless Powder Saturday morning at Cabela’s.

I make my own charcoal by pulling out the charcoal chunks from the wood stove every morning and saving them. These are then finely ground to “Air Float” in an electric coffee grinder. This results in my cost per pound to make my No.7 being $8.26.

Acquiring chemicals results in an actual higher initial cost. I acquired some chemicals in lots of one to five pounds, plus cost of shipping if chemicals cannot be acquired locally increases total cost; but it still remains quite a bit lower than commercial powder of similar utility in the .308 Winchester; such as my cast boolit loads using BLC-2 powder.

[dverna]

Good write up Mustang

[firefly1957]

Last week I tried a mix I think I read of in this thread 87% Ammonium Nitrate 13 % Charcoal (oak in my case) .
I have ground Ammonium Nitrate and charcoal together in the past and found it sucks water from the air . What I did this time to help with that was grind 87 grains NH4NO3 with 13 grains Charcoal with two eyedroppers full of a mix of 2/3 acetone and 1/3 watch spray Lacquer . The dried results looks a bit like Pyrodex and will not burn from a match a torch gets some small flames after it melts .

I put 8 grains in a .45 acp case primed with a Winchester large pistol primer and loaded it in my test fixture it fired sounding about normal the primer was slightly flattened . More tests need to be done before I put a Chronograph in front of it .
Let's see if I can post a picture of test fixture ? P.S> that is a damaged 1911 barrel welded in steel "u" channel .

[2TM101]

Last week I tried a mix I think I read of in this thread 87% Ammonium Nitrate 13 % Charcoal (oak in my case)

This is "Ammonpulver" Its what Germany used near the end of both world wars, and the new Soviet Union used until they could get regular smokeless powder factories up and running. But don't worry about finding any of this ammunition surplus - it doesn't exist now.

Ammonpulver leaves an ugly corrosive residue on everything and even the best cleaning won't get all of it. The brass case itself will disintegrate in a matter of months. This is serious last resort stuff here.

[2TM101]

I am not poo poo ing the comment on Toxicity of any/all of the chemicals used; but has anyone taken the time to read the MSDS (Manufacturing Safety Data Sheets) on any of the day to day items found under your kitchen and bathroom sinks? Has anyone noticed the proliferation of "California Hazard Warnings" on the daily products we buy? 99.9999% of those active on this and other similar firearm related sites are "EXPOSED TO LEAD"; ohhhhh my Goodnessssss - we are all going to die!

I have on my desk in front of me a product that has an expiration date and a label that the contents can cause cancer.

Its water.

Anyway, sounds like your #7 behaves like either black or one of the other alternate powders we have been trying out lately, though in this case even more sensitive to the size. So far my own resistance to making a Smokeless powder substitute is not having a good way to tell what pressures I am actually getting. I don't know at what point primers start to flatten - or how close to TOO MUCH I am at that point.
So what pressure does this #7 produce? See anything like this?

[barnetmill]

Does the purchase of the various chemicals stir up any interest from Homeland or ATF? Does anyone care?

I certainly applaud the effort and resourcefulness of the posters.

[MUSTANG]

I have on my desk in front of me a product that has an expiration date and a label that the contents can cause cancer.

Its water.

Anyway, sounds like your #7 behaves like either black or one of the other alternate powders we have been trying out lately, though in this case even more sensitive to the size. So far my own resistance to making a Smokeless powder substitute is not having a good way to tell what pressures I am actually getting. I don't know at what point primers start to flatten - or how close to TOO MUCH I am at that point.
So what pressure does this #7 produce? See anything like this?

See Post # 85 above. So far all the Tests have primers as depicted in that posting. No indications of pressure signatures with 33 Grains of No.7 in a 308 Winchester case with bullets/boolits ranging from 15 grains to about 200 grains.

Not sure how this powder will perform in rounds other than the .308/30-06/8mm Mauser range with those bullet weight ranges. My supposition is that it might work OK in a 38/357; but at lower velocity. Will not be able to take that fork in the road for some time as I pursue the ins and outs of the current path.

[firefly1957]

This is "Ammonpulver" Its what Germany used near the end of both world wars, and the new Soviet Union used until they could get regular smokeless powder factories up and running. But don't worry about finding any of this ammunition surplus - it doesn't exist now.

Ammonpulver leaves an ugly corrosive residue on everything and even the best cleaning won't get all of it. The brass case itself will disintegrate in a matter of months. This is serious last resort stuff here.

I am just experimenting ine the past I have seen WWI use of 60/40 mix of ammonium Nitrate to charcoal that is one that turned to soup as I mixed it up on a humid Michigan morning .
I just recently got 5 pounds of older HS-7 cheap it should keep the .45 going for my lifetime ! I was pretty much set with 5 grains Red dot but ran out and last two times to the store none in stock !
It is hard to find data for HS-7 in .45 acp but I have a little in older manual....

[ofitg]

Anyway, sounds like your #7 behaves like either black or one of the other alternate powders we have been trying out lately, though in this case even more sensitive to the size. So far my own resistance to making a Smokeless powder substitute is not having a good way to tell what pressures I am actually getting. I don't know at what point primers start to flatten - or how close to TOO MUCH I am at that point.

Just throwing an idea out here..... if you had velocity measurements from two different barrel lengths (say, 4 inches, 8 inches), they should indirectly reflect two separate points on the pressure/time curve.
With a program like QuickLoad you could run simulations with commercial powders, looking for one that had similar results?

[2TM101]

No indications of pressure signatures with 33 Grains of No.7 in a 308 Winchester case with bullets/boolits ranging from 15 grains to about 200 grains.

I see that and I wonder just how much stronger this is than the black powder substitute stuff we have been making. Obviously more, but how much more.

[2TM101]

I am just experimenting in the past I have seen WWI use of 60/40 mix of ammonium Nitrate to charcoal that is one that turned to soup as I mixed it up on a humid Michigan morning .

Ammonpulver is more like 85/15 but I don't know what the preparation method was. It may have been mixed dry. The ultra corrosivity of this stuff scared me away from ever trying it. The amount of Ammonium Nitrate in this #7 makes me wonder

[perotter]

Thanks for the reports on your work and the success you are having.