4F Main Charge

[jimbo15563]

I had a conversation about hunting the late PA Flintlock season at the local watering hole a few days ago. The subject was firing dependability in bad weather. One of the guys said he never had a problem with his flintlock. When I asked him his "secret", this is what he told me:

First, he said, drill out your touch hole. (I forget what size he told me)Next, spread some of your FFFF priming powder out on a newspaper and spray it with silicone waterproofing. After it dries, break up the clumps and use it in the pan. Then he told me that he uses 90 gr of 4F for the main charge under a .50 PRB. He also mentioned that he had to plug the touch hole to keep the powder from running out when loading. When I questioned the wisdom of this load, his reply was that he's been doing that for "years".

From my limited experience, this advice runs counter to everything I've learned. While I have no doubt that his rifle "goes off every time", The only reason I can think of as to why he hasn't blown himself or somebody else up is that the touch hole is drilled out sufficiently to relieve some of the pressure.

What I was hoping to do by posting this is to solicit some comments which I can print out and show him. I would hope that the posts would be non-inflammatory (calling him an idiot would be counter productive) and provide some good, factual evidence as to why he shouldn't do this.

Jimbo

 

[xxgrampa]

hi ho jimbo,

i know of no reason why he should't do that. a 4F main charge is not unusual. don't think there is anything to gain by it. but, if it gives him confidence in his load, why not. shooting is mostly between the ears.

never heard about the silicone on the priming. will have to give it a try. thank him for me about the tip..

..ttfn..grampa..

 

[Norskie]

I'd be very concerned about a pressure spike with that much 4f. That stuff burns mighty fast. Since we don't know how stout the breech of his gun is, we can't generalize his method to any other flintlock. "I've been doing it for years" speaks nothing to what will happen the next time he does it.
Get a copy of Sam Fadala's loading data book; show it to your aquaintance. I disremember the name. I don't agree with all of his conclusions, but Dr. Sam certainly has put time and thought into these matters.
Moose

 

All of this sounds like bad advice--or a bad joke.

 

[Mike Brooks]

I know of a few fellows who use 4ffff as a main charge in micro calibered guns, .25-.29. I've never heard of anyone else doing it on anything else. A bit too fine for me. 3fff is plenty fine enough.
I have trouble with 4ffff absorbing moisture and turning into gooo. Maybe that's what the silicone treatment was all about.
Bottom line, I reccomend against it.

 

That is one accident waiting to happen. I'm sure his widow's lawyers will say it's faulty manufacturing, or bad powder. Like Dryballing, it'not a matter of If, but when. Even with a larger touch hole, that's gotta be like a load of 160 or mor grains of 2F pressure wise. manure like that gives us all a bad name.

Bill

 

[Headhunter]

In all I have ever heard or read...............................Sounds like BAD JU-JU to me.

Headhunter

 

[ky_man]

I'm reading in "A Course of Instruction in Ordinance and Gunnery" (J.G. Benton, pub. 1867) that "It may be shown by direct experiment that the burning of a grain of powder in a firearm, is progressive, and that the size of the grain exerts a great influence on the velocity of the projectile, especially in short arms."

"For this purpose, take a mortar eprouvette and load it with a single fragment of powder weighing 46 grains; fire it, and the ball will not be thrown out of the bore. Divide the same weight into 7 or 8 fragments, and it will barely be thrown out of the bore; divide it into 15 fragments, and it will be thrown 10 feet; 50 fragments will throw it 30 feet; and the same weight of cannon powder, 170 feet."

Seems to me like this is indicating a proportional increase in pressure with decreasing grain size. Of course, the grains they are using are relatively large. I'd bet this trend flattens out somewhat as the grains get progressively smaller. What would happen, after all if the size of the grains were reduced to just above the molecular level?

Powder burns progressively. When you fire a rifle with just powder, a lot of still-burning grains are ejected. The smaller the grains were to begin with, the faster the powder burns, and less unburned powder is ejected (i.e., more was combusted in the bore). This is because the powder burns from the surface in towards the center, and with 4F since the grain size is smaller this process takes less time to complete.

Personally, I've never tried 4F in a rifle. I don't see why it couldn't work safely, but this depends on the individual, and I would not recommend it for everybody. I'd back off on the amount used to prevent building up excess pressure.

 

[Blizzard of '93]

Some will be dependent on the length/strength/condition of the barrel and bore size. Also projectile weight and nipple/drum condition. Caution is called for here. :nono:

 

[bob308]

i dout he will have a problem if the touch hole is bored aout that big. just dont stand on the lock side of the gun when he fires it. but for that matter i would stand around him at all. as far as trying to show him he is wrong don't waste you time he knows it all.

 

[biliff]

The GOEX website shows 4F as "priming only". Its load data tables do not list any charges for FFFFg even for the small bores.

 

[bob1961]

Then he told me that he uses 90 gr of 4F for the main charge under a .50 PRB.

i only use 70 gr 3f under my .490 ball :shocked2: :v ..........bob

 

[roundball]

Personally I'd be very afraid of that much 4F.

Last year I actually conducted range tests using a left over pound of 4F as main charges in .45/.50/.54/.58cal TC and GM barrels.

To an extent, I proved to myself that simply as a powder, 4F does in fact work as a main charge...it was very accurate and left virtually no fouling..

Also had the problem of losing 4F out the vent...the first couple times I seated a ball it blew most of the powder right out.

BUT..........starting at 20-30 grns, I gradually worked up to 50grns and stopped there because I could tell the recoil was gradually increasing and by the time I got to 50grns I speculated / worried that going any higher would be crossing the line into pressures that might be unsafe.

My tests were not scientific but I'm not an idiot either...was completely alone at a private range, paid very close attention to what I was doing, looked for any signs of increased pressure/recoil, etc...and everything was fine until I got to 50grns and concluded that was the max 4F ceiling for me, on that day, with my equipment, my components, my procedures, etc.

I have no future plans of using 4F as a main charge for hunting or anything else...it was just a first hand experiment...and I can't imagine what the pressures and recoil must have been like if that guy used 90grns of 4F.

PS: It'll be interesting to see if a particular individual jumps in here as he did last time there was a 4F discussion, with his gutter level stream of borderline 4 letter words describing how wrong it was to even have such a conversation on a public forum for fear somebody will misunderstand what they read, run out and hurt themselves, etc. :shake:

Maybe he was drunk like your conversation partner may have been talking about 90grns 4F :grin:

 

[tg]

I do not think you will find any valid loading data or recomendations for 4f in a .50 rifle, it is considered dangerous and jury rigging powder and vent to "make " it work would not likley be recomended by any builder or manufacture, I hunt in some of the wettest country in the states and have no problem with 3f as a main and primeing charge, if the lock is well tuned the touch hole of adequate size and common sense is used in protecting the prime and lock from moisture, cows knee wax pan cover, keep barrel pointed down, tuck lock under arm, are some basic methods. Some folks do what many consider strange in this sport, advocating 4f as a main charge is generaly considered irresponsible considering that newcommers may be at risk if they follow such advise, I hope no harm comes to this fellow and my intent is not hostile toward him but he should not suggest such a practice to others.

 

[Walks with fire]

I for one am never going to use 4f for the main charge and am also not real keen on using 3f for a main charge in a 50 caliber or above. I know many people do use 3f but my TC's load book states 2f and it works for me just fine.

I use a piece of leather made for car washing; (chamois) heat it up with a hair drier and put sno-seal boot waterproofing on it. It wraps around the lock really well and seals out snow and rain really well. Many times I don't put the pan charge in until it's time to shoot.

 

[tg]

I think you will find the only potential downside to 3f in the larger cals. is with stout loads that can cause breech erosion when cutting down the volume by 20% when useing 3f instead of 2f in .50 -.62 guns, the use of 3f has become more popular of late and a reduced load is genearly recommended to extend barrel life.

 

[Walks with fire]

Green Mountain barrels even provide max load data for 3f in their big bores so I guess it's safe enough within reason; but, I do think it is a little harder on the barrel.

 

[roundball]

It's all the same black powder...it's just smaller granulations so it burns faster...the key is to reduce the 3F charge when substituting it for 2F...the industry rule of thumb is 10-15%...ie: If you normally use 100grns 2F, just use 85grns 3F...I use Goex 3F in everything from .40cal to .62cal...fast, clean, and accurate.

 

[blacksmithman64]

Ain't no way. ffffg is for priming flinters. That fella's asking for a burst barrel and I hope he ain't on a firing line with me or any one else somewhere. :shake: It doesn't matter if "it works"; it matters if its safe.

 

[xxgrampa]

hi ho again jimbo,

what i don't understand is, how he can stand the recoil. that load of 90gr 4F has to kick like a mule. can't imagine trying to site in a load like that.

..ttfn..grampa..