4F Black Powder Question

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In other words you would work up a load with 4f, the same as you would with any other powder, starting low and working up to the optimal load?

As above. With an eye towards velocity and pressure. As I would developing a load for my .58 with NullB, or 0B that I ground even finer. ‘Optimal’ to me is the product of burn speed and barrel length so a charge of finer powder that produces the same velocities/pressures as a coarser powder wouldnt need that extra foot or two of barrel, just as too much course powder with too little barrel is blown out the muzzle still burning. I highly doubt it’s unsafe in modern barrels, but outside of economics I don’t necessarily think it’s a better way to go in a longbarreled rifle. I could be wrong and as I said, I’ve never considered it, so the thread is of interest to me as an intellectual exercise. I’m always open to learn something new.
 
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There may be some confusion between the propagation of the flame front from the ignition source and the deflagration of the individual grains. These are not the same thing. In a non compressed charge the flame front propagation through the interstices is little affected by the grain size. In even NullB sizes the gaps are continental in size compared to the molecules of the ignition source. Once the flame front has raised the temperature of the skin of the grain to self ignition then the grain burns and ablates at the same speed. The small grain simply has less far to burn so gives up it's energy as several small individual burns. The larger grains are heat sinks in themselves so they do burn more slowly but the major speed determinant is the volume of the grain. Thus a small grain does burn it's charge faster and sooner. Hence with an earlier and sharper peak and a higher peak pressure. Black powder has a complicated nature and there are potential inputs from adiabatic heating as well as flame propagation not to mention the effect upon the produced gasses from the temperature of the burn causing them to expand from the heat as well as their own production.

Again the end result is that finer powders do produce higher, earlier and sharper pressures than coarse ones. This is a genuine hazard. However, as to whether this is enough to constitute an actual danger in an individual barrel is a different question and forms the actual risk. The hazard is genuine but the risk is a matter of judgement in the individual case. My (unqualified) assessment is that I would use 4F in a 0,320" barrel but I would not in one larger than 0,450" In between I am uncertain.

Others may have different opinions on the risk and are entitled to differ just as barrels differ in many ways; but the physics of the hazard are well established and have been the subject of academic and industrial practical experimentation and peer reviewed papers over generations.

With sufficient barrel thickness and quality of steel a shoulder arm or pistol can cope with any charge for such use held by a human. But when scaled up to the largest artillery guns it was found impossible to build guns with sufficient suitable metal to resist the sharp, early and high peak pressures of fine (in artillery terms) grain black powder. The solution was to make the grains enormously large which let them burn more slowly throughout the length of the barrel. This allowed larger charges with greater ranges, heavier shells or in lighter builds. This is just the same issues as the OP but just writ large. The principles apply at all scales from 4F to siege gun artillery pebble powder. The other change applied to artillery was to change from Black powder (fully carbonised vegetable material) to Brown or Cocoa powder which is only partially carbonised. Again the purpose was to burn more slowly to distribute the powder's power over a longer period to give the same power but at a lesser peak pressure. A look at the the world's biggest black powder gun may be of interest. It would be impossibly heavy to make, mount and use without the inventions of pebble and brown powder.
 
Nope, I did understand your theory the first time and no I still disagree.
Despite there being many flawed assumptions in your theory/s the main on is the common misconception of flame front differences in different granulation sizes.
With large granulation the flame front can in fact move through the column quicker aided by the voids naturally present.
With finer grades the voids are less.
Remember the powder is not loose but compressed, compression increases once burning starts but is yet not complete!

It is this explanation that demonstrates the increase in chamber pressure for the finer granulations but in no way indicates a dangerous situation.
One is simply observing the lower volume initially working on yet to be ignited powder (near solid) and projectile. Once things start to move it all balances out.
It is a splitting of hairs and one over the other in terms of accuracy shooting wise is a mute point. One is simply changing barrel harmonics or vibrations of the whole system and or changing the effects on the projectiles nature internally.
As for time difference in the differing powder granulation it is probably closer to talk of the difference in nano seconds, not milliseconds!
There is far to much assuming in this discussion. Humans have a tendency to try and explain stuff to help themselve understand rather than get to the truth of a matter. I do it, everyone does it.
Give me all you 4f and keep your 1&2f, useless stuff 😆

B.
Can't give you my 4f. I need it. I don't use no new fangled percushiny cappy things. Rock scratchers are what I shoot.
 
I'll try one more time. Maybe I'm not explaining clearly enough. After that you either accept the physics or not. No skin here.
Given equal amounts by weight of an ideal powder and condition where the only variable is the grain size. Flame propagation is slower with the larger particles than the smaller ones. This equates to a production of gases over a longer period. This creates a constant pressure even as the chamber size increases because the projectile is going down the barrel.
With smaller grains all the gasses are produced before the projectile reaches the muzzle. This creates a maximum pressure point at one chamber volume and then decreases as the projectile moves down the barrel and the chamber volume increases. There is also a very slight decrease in temperature of the gasses as they expand, further decreasing pressure. You can add more powder so that the burn time is longer (talking milliseconds) but that also means an overall higher pressure.
Today's solid forged barrels of high quality steel will probably never have an issue with anything other than insane over loading conditions using different formulas of powder / nitro powder.. But the increased pressure will cause two conditions that a correct load doesn't. First as I said the turbulence at the muzzle as the projectile clears. It will also push the limits of the lead / patching to hold the rifling. Both conditions have proven detrimental to accuracy.

Here is something from Wideners on reloading cartidges.


If you want your head to really hurt. Here is a rudimentary flame turbulence equation. τf = lt/u′, where lt is the integral scale of turbulence .


Extreme example and strictly cautioned against!!!
You could determine the total gas production of a double base nitro powder. Why wouldn't you use that in a muzzle loader??? Because under confinement the flame propagation of nitro powders is very much faster than BP and theoretically would produce all the gasses before the projectile even starts to move.. creating HIGHLY DANGEROUS over pressurization at the chamber. Regardless of the fact that total gas amount would be the same as a BP load.

I was president and CTO of a small company that sought to produce an alternative propellant/black powder replacement. Actually black powder burns faster than smokeless powders. Doesn't reach same high pressures, though, and pressure does not affect burn rate of black as it does so greatly with smokeless. Smokeless has progressive burn rate. Try burning a loose pile of smokeless vs black powders!

There are several other differences between black & smokeless powder energy release characteristics. Larger powder granules take longer to burn to completion, so coarser powder gives slower bullet acceleration in bore. Each granule burns from the outside inward. Black powder reaches its peak pressure and remains there until all is burned. Coarser black powder in larger bores makes good sense.

FWIW & FYI, I have loaded and shot 30-06 ammo with 2fg black powder and jacketed bullets. Got similar velocity as with normal smokeless. Burned surprisingly clean, too! I don't recommend this, but wanted to know, so gave it a try.
 
Can't give you my 4f. I need it. I don't use no new fangled percushiny cappy things. Rock scratchers are what I shoot.

"Back in the day", separate priming powder was a luxury the way I understand it, and most pans were primed with the same powder as used in the main charge.

So you really don't need that 4f. :)
 
So you are saying that with the ideal grain size, pressure remains constant while the bullet travels through the bore. Is this an observation of pressure readings from an actual load? Or just a theory of an unobtainable hypothetical scenario?
Theoretical physics backed by math..... Unless you have several thousand dollars you don't need. Given the money I could buy a couple of hundred piezo sensors, a test barrel, and a powerful computer to take pressure readings every say, 5 mm. Now that would be a fun weekend!
 
I was president and CTO of a small company that sought to produce an alternative propellant/black powder replacement. Actually black powder burns faster than smokeless powders. Doesn't reach same high pressures, though, and pressure does not affect burn rate of black as it does so greatly with smokeless. Smokeless has progressive burn rate. Try burning a loose pile of smokeless vs black powders!

There are several other differences between black & smokeless powder energy release characteristics. Larger powder granules take longer to burn to completion, so coarser powder gives slower bullet acceleration in bore. Each granule burns from the outside inward. Black powder reaches its peak pressure and remains there until all is burned. Coarser black powder in larger bores makes good sense.

FWIW & FYI, I have loaded and shot 30-06 ammo with 2fg black powder and jacketed bullets. Got similar velocity as with normal smokeless. Burned surprisingly clean, too! I don't recommend this, but wanted to know, so gave it a try.
A company I might know?
There are a bunch of different nitro powders and all burn at a different rate. That's why I have to use a specific powder for each different cartridge gun I reload. What shoots well in my M&P2 9mm slams back the bolt on my M1 carbine and won't cycle. I've tried several different loads to out think the manufacturers and it didn't work. If they don't have a recommended starting load for the caliber/ cartridge/ bullet weight, it just won't work. Even trying to match the burn speed for different man / powders. (see chart)
But since I ended up with several pounds of assorted Hodgdon, IMR, Alliant, Goex, Swiss, Vihtavuori, and Winchester powders and a slow weekend I made a "test track" out of 1/2"square track aluminum. I filled the track over a set 6 inches with a lead in to eliminate ignition lag. It was fun and I learned quite a bit. First , the most important difference in burn time isn't granular shape or even size. It's the formula. No big differences in speed of ball, rod, or disc as long as the formula speed was ~equal. I also proved what I had been told by the old timers at the pyro Assn. It's the charcoal in the home brew BP. Pine charcoal is almost useless, just better than Kingsford. Willow, basswood and even coconut fiber charcoal are by far the fastest burning. I found that my meal powder grill charcoal powder was measured in minutes, Willow run through a 4 mesh (about cannon grade) was around the same speed as H1000 and willow through a 20 mesh (~4f) was faster than the Red dot.

Not saying that was what happened, but some one COULD have actually set up races, But I wouldn't have done that . It would have been childish and immature.... but probably a lot of fun... But I didn't do that and no one can prove I did.;)
 

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A company I might know?
There are a bunch of different nitro powders and all burn at a different rate. That's why I have to use a specific powder for each different cartridge gun I reload. What shoots well in my M&P2 9mm slams back the bolt on my M1 carbine and won't cycle. I've tried several different loads to out think the manufacturers and it didn't work. If they don't have a recommended starting load for the caliber/ cartridge/ bullet weight, it just won't work. Even trying to match the burn speed for different man / powders. (see chart)
But since I ended up with several pounds of assorted Hodgdon, IMR, Alliant, Goex, Swiss, Vihtavuori, and Winchester powders and a slow weekend I made a "test track" out of 1/2"square track aluminum. I filled the track over a set 6 inches with a lead in to eliminate ignition lag. It was fun and I learned quite a bit. First , the most important difference in burn time isn't granular shape or even size. It's the formula. No big differences in speed of ball, rod, or disc as long as the formula speed was ~equal. I also proved what I had been told by the old timers at the pyro Assn. It's the charcoal in the home brew BP. Pine charcoal is almost useless, just better than Kingsford. Willow, basswood and even coconut fiber charcoal are by far the fastest burning. I found that my meal powder grill charcoal powder was measured in minutes, Willow run through a 4 mesh (about cannon grade) was around the same speed as H1000 and willow through a 20 mesh (~4f) was faster than the Red dot.

Not saying that was what happened, but some one COULD have actually set up races, But I wouldn't have done that . It would have been childish and immature.... but probably a lot of fun... But I didn't do that and no one can prove I did.;)

And just what might this have to do with the OP’s question?
Can 4F be used as a main charge powder?
 
For some reason it seems that I have 3 pounds of 4F powder that I have accumulated over the years. I have a ,45 caliber flintlock which I always use 3F for my main charge. I'm aware that 4F is indicated for a priming powder.
It will take me forever to go through 3 lbs of 4F if I use it only for priming.
Can 4F be used as a main charge powder? I have a digital scale and I was going to weigh out 70 grains of 3F and 4F to see what the volume difference would be. Thoughts?
For the last 40 years, I have been told to NOT use 4f for the main charge. You might get away with it for a while, but there are too many variables that could cause disaster. Like an accidental double charge or double ball load. Unless you shoot alone, you risk the lives of those around you. And when people find out you hurt someone because you needed to get rid of some 4f powder, guess what type of idiot they will call you.
A man and his son were hunting and the father used regular high power rifle powder in his front stuffer. When they both discharged their rifles that evening, both were killed.
These rifles are not toys, obey the safety rules.
 
Smokeless powder is a long way from 4f black powder. I’m still waiting for someone with firsthand knowledge to report a gun failure from 4f that didn’t involve some other mistake.

BTW I don’t use 4f except in the pan.
 
For the last 40 years, I have been told to NOT use 4f for the main charge. You might get away with it for a while, but there are too many variables that could cause disaster. Like an accidental double charge or double ball load. Unless you shoot alone, you risk the lives of those around you. And when people find out you hurt someone because you needed to get rid of some 4f powder, guess what type of idiot they will call you.
A man and his son were hunting and the father used regular high power rifle powder in his front stuffer. When they both discharged their rifles that evening, both were killed.
These rifles are not toys, obey the safety rules.
Utter nonsense. Again you, another one have linked anecdotal stories to a supposed hazard of using 4f.
What is it with you people?
How can anyone of sound mind link a story of people loading a muzzle loader completely wrongly with smokeless powder to the use of 4f? Utter nonsense.

What are people going to say if someone's gun blows up but they were using 1f? That that is okay?
Tell me please, please please tell, anyone, please please tell me. Just when did a gun blow up and it was found to be because of 4f and so they hung the user? Please tell me because I sick of all the dumb horror stories. Sometimes on here it's worse than Halloween!

Please please supply not stories but scientific facts about how I have it wrong. That's all I have ever asked.
Not whitter, facts. Not chocolate mixes for cannon or using pebbles. Just facts like ones that the powder manufacturers would use to direct us with by printing on their containers maybe 🙄. Why even some unmentionable powders have bold print warnings on the container but I ain't ever seen a can of 4f with not for main charge written on them!
Oh and by the way. I have on numerous times loaded double ball loads on wait for it.......4f! And it gets worse, I've been known to load heavy shot loads on 4f too 😱
Fact..... anyone? Please.
 
A man and his son were hunting and the father used regular high power rifle powder in his front stuffer. When they both discharged their rifles that evening, both were killed.
These rifles are not toys, obey the safety rules.

Was this regular 4f rifle powder? Cuz if it was cf reloading powder that's not really relevant here?? I knew a guy that could get salt free so he used it for filler in his revolver instead of cream of wheat and all the grass died at his back yard range.
 
I used to be an emergency planning officer in the course of which I had need to look at many events which were termed 'accidents'. Like an arms discharge there are no 'accidents' but only 'incidents' and nearly all would qualify as negligent ones in arms handling terms.

I cannot even begin to count the number of times the reports quoted words to the effect of 'It always worked fine. Right up to the point when it didn't'...... Just because one gets away with a risk does not stop it being a risk. I travelled thousands of miles with no seat belt in cars before seat belts were (sensibly) compulsory and over many years and suffered no injury. Does that mean riding in a car with no seat belt is safe?

'Not chocolate mixes for cannon or using pebbles.' May I suggest that you support your reasoning by doing some decent internet research on these matters and the millions spent by industry and governments upon the matters because you clearly have no idea what 'cocoa' powder is nor 'pebble' powders are and how they are relevant to the subject.

I hI have said that I have doubts if the extra risk of 4F is very great but it is an actual risk. I am not saying that all guns, or indeed most guns, would burst with the use of 4F. I am saying is that it edges the gun closer to a chance of it. Not by much, but it does edge it closer. 4F at the same charge will impose more strain upon the barrel than a coarser powder. That one gets away with it due to a sufficient tolerance in the construction of one's gun does not stop the extra strain being present. Only that one has taken a (possibly very minor) extra risk and got away with it.

The thought does occur to me that, like insure and ensure, some may not understand that hazard and risk are not synonymous. Look them up if one is confused.

The artillery examples I used are very relevant. They merely make the matter more evident by virtue of the larger scale but the physics are the same. Read up on these large artillery guns and the evolution of their construction and powders because governments around the world spent many, many millions of dollar or pounds in modern terms upon researching the reasons why they could not use large small grain powders charges without the guns bursting and investing in using powders with a slower burn rate to alleviate the issue.

Look at the black powder sporting use manufacturers recommendations and the trend is universal. They recommend coarser powders for the larger bores and finer for smaller ones. They make their powder in several grades. Why if one can use 4F for all shooting purposes?

I finish by repeating that the risk of using 4F is possibly very small and may be fine in small bores but the hazard exists nevertheless. The physics is quite clear and has been demonstrated in theories since the 17th century and backed by scientific testing in the 19th century at great length that, ceteris paribus (look it up if you are not familiar with the term), a fine grain black powder produces more strain than a coarser one.
 
Utter nonsense. Again you, another one have linked anecdotal stories to a supposed hazard of using 4f.
What is it with you people?
How can anyone of sound mind link a story of people loading a muzzle loader completely wrongly with smokeless powder to the use of 4f? Utter nonsense.

What are people going to say if someone's gun blows up but they were using 1f? That that is okay?
Tell me please, please please tell, anyone, please please tell me. Just when did a gun blow up and it was found to be because of 4f and so they hung the user? Please tell me because I sick of all the dumb horror stories. Sometimes on here it's worse than Halloween!

Please please supply not stories but scientific facts about how I have it wrong. That's all I have ever asked.
Not whitter, facts. Not chocolate mixes for cannon or using pebbles. Just facts like ones that the powder manufacturers would use to direct us with by printing on their containers maybe 🙄. Why even some unmentionable powders have bold print warnings on the container but I ain't ever seen a can of 4f with not for main charge written on them!
Oh and by the way. I have on numerous times loaded double ball loads on wait for it.......4f! And it gets worse, I've been known to load heavy shot loads on 4f too 😱
Fact..... anyone? Please.

Well Britsmoothy, I guess all those idiots that wrote books saying don't use 4f for a main charge are just idiots and don't know what in Hell they are talking about. Because Britsmoothy wrote a post on a forum and said since it hasn't killed him yet it is perfectly safe for everyone. Many experts, and you aren't one of them, have warned against the danger of using 4f except for priming powder. But with your luck and limited kinowledge, you have decided to tell everyone not to listen to experts, but instead trust you with their and others lives. How about telling children to play on the freeway because no child has been killed playing on the freeway yet. On a stick of dynamite, it does not say " DO NOT STRIKE WITH A SLEDGE HAMMER" I guess the manufacturer believes that most people have enough common sense not to. Hope you have a good lawyer.
 
Well Britsmoothy, I guess all those idiots that wrote books saying don't use 4f for a main charge are just idiots and don't know what in Hell they are talking about. Because Britsmoothy wrote a post on a forum and said since it hasn't killed him yet it is perfectly safe for everyone. Many experts, and you aren't one of them, have warned against the danger of using 4f except for priming powder. But with your luck and limited kinowledge, you have decided to tell everyone not to listen to experts, but instead trust you with their and others lives. How about telling children to play on the freeway because no child has been killed playing on the freeway yet. On a stick of dynamite, it does not say " DO NOT STRIKE WITH A SLEDGE HAMMER" I guess the manufacturer believes that most people have enough common sense not to. Hope you have a good lawyer.
Curious, do you feel safe shooting any powder granulation, let it be 1F, 2F, 3F, or heaven forbid, 4F? What about the subs with higher pressure than black powder - what happens if someone uses weight or doesn’t reduce volume? Clue, the guns don’t blow up.

Have you not read the posts in this thread about tearing down War of Northern Aggression era cartridges with finer than 4F powder in them? Or the 1st edition Lyman Black Powder with 4F loads in it? Or photographs of 4F powder cans from the 1960s with the fine print stating it was suitable for musket, pistol and shotgun? I know, there are numerous instances of muzzleloaders blowing up from 4F, they just have not been made public yet. Why don’t you post a few? I can’t seem to find them.

I have used superfine blackpowder, call it 4F since the 1960s, in original and replica guns. Why? Because that is what was used. If you could, you used the granulation that worked best as far as accuracy, or used the granulation you had if that was all that was available. Always adjusting charge based on granulation. Still shooting originals and replicas here.

Guessing if you were shooting a 50 caliber muzzleloader, and you didn’t have 2F powder, you would be shut down, even though you had pallets of 1F, 3F and 4F black powder available, correct? If not, why?
 
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Well Britsmoothy, I guess all those idiots that wrote books saying don't use 4f for a main charge are just idiots and don't know what in Hell they are talking about. Because Britsmoothy wrote a post on a forum and said since it hasn't killed him yet it is perfectly safe for everyone. Many experts, and you aren't one of them, have warned against the danger of using 4f except for priming powder. But with your luck and limited kinowledge, you have decided to tell everyone not to listen to experts, but instead trust you with their and others lives. How about telling children to play on the freeway because no child has been killed playing on the freeway yet. On a stick of dynamite, it does not say " DO NOT STRIKE WITH A SLEDGE HAMMER" I guess the manufacturer believes that most people have enough common sense not to. Hope you have a good lawyer.

Swiss 4F is marketed as a main charge powder. How do you explain that, or the Lyman data on 4f charges, or the regular use of 4f and finer in WTBS era rifles and pistols?

What you are believing about 4f being "dangerous" is urban legend, internet lore,. old wive's tales and self delusional nonsense.

Use what you want, but don't go a round trying to put fear into people to no purpose with no evidence. We have enough of that going on in this country right now as it is.
 
I used to be an emergency planning officer in the course of which I had need to look at many events which were termed 'accidents'. Like an arms discharge there are no 'accidents' but only 'incidents' and nearly all would qualify as negligent ones in arms handling terms.

I cannot even begin to count the number of times the reports quoted words to the effect of 'It always worked fine. Right up to the point when it didn't'...... Just because one gets away with a risk does not stop it being a risk. I travelled thousands of miles with no seat belt in cars before seat belts were (sensibly) compulsory and over many years and suffered no injury. Does that mean riding in a car with no seat belt is safe?

'Not chocolate mixes for cannon or using pebbles.' May I suggest that you support your reasoning by doing some decent internet research on these matters and the millions spent by industry and governments upon the matters because you clearly have no idea what 'cocoa' powder is nor 'pebble' powders are and how they are relevant to the subject.

I hI have said that I have doubts if the extra risk of 4F is very great but it is an actual risk. I am not saying that all guns, or indeed most guns, would burst with the use of 4F. I am saying is that it edges the gun closer to a chance of it. Not by much, but it does edge it closer. 4F at the same charge will impose more strain upon the barrel than a coarser powder. That one gets away with it due to a sufficient tolerance in the construction of one's gun does not stop the extra strain being present. Only that one has taken a (possibly very minor) extra risk and got away with it.

The thought does occur to me that, like insure and ensure, some may not understand that hazard and risk are not synonymous. Look them up if one is confused.

The artillery examples I used are very relevant. They merely make the matter more evident by virtue of the larger scale but the physics are the same. Read up on these large artillery guns and the evolution of their construction and powders because governments around the world spent many, many millions of dollar or pounds in modern terms upon researching the reasons why they could not use large small grain powders charges without the guns bursting and investing in using powders with a slower burn rate to alleviate the issue.

Look at the black powder sporting use manufacturers recommendations and the trend is universal. They recommend coarser powders for the larger bores and finer for smaller ones. They make their powder in several grades. Why if one can use 4F for all shooting purposes?

I finish by repeating that the risk of using 4F is possibly very small and may be fine in small bores but the hazard exists nevertheless. The physics is quite clear and has been demonstrated in theories since the 17th century and backed by scientific testing in the 19th century at great length that, ceteris paribus (look it up if you are not familiar with the term), a fine grain black powder produces more strain than a coarser one.


I am a trained Master Exercise Practitioner (MEP) myself having been to school with FEMA at Mt. Weather and the Maryland Firefighters Academy, so I know a bit about incidents and accidents myself.

I have yet to see any incident or accident related to the use of 4f as a main charge, so I am going to say there is no risk greater than using 3f whatsoever. Especially seeing as depending on the brand, there are batches of 3f that are proven more energetic than 4f. So if 4f is a risk, 3f is a greater risk.
 
If you use too much 4F you might blow something up?
Oh golly gosh who'd a thunk!
Let's argue a while about the right thickness for a miniball skirt.
 
Well, to be fair, I looked in the Lyman black powder Handbook & loading Manual. I saw no rifle loads for 4f black powder. I checked Wikipedia which lists 4F for extreme small bore pistol and priming. I checked Pyrodex. I saw RS for 2F and P for 3f but nothing for 4f. I looked at a Field and Stream article which lists 3F for small bores. 4F was not mentioned for a rifle powder. I checked Pedersoli and other companies for their recommended loads for their rifles. None listed 4F as a recommended charge for their rifles. I am not going to change your mind, and you will not change mine. I do ask that you tell new shooters the truth when you advise them about powder choices. That you use 4F even though most companies do not recommend it.
 
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