FFF - 3.5F - FFFF : Boom?

[Mad Monk]

Old Ironsights,

Within the 3Fg size range designation you may expect to see a good bit of difference from one powder manufacturer to the next and small differences within a brand. You can have a lot of 3Fg that is coarse and another that is fine.

That can be looked at by using several screens. I went back into my records for an example of this.
In May of 2000, GOEX brought into the U.S. a single container of black powder made by KIK-Kamnik in Slovenia. The container held 26,369 pounds of KIK-made black powder at a price of $3.20 per pound P.O.E. Packed in tin cans by KIK-Kamnik.
GOEX had visited the plant in Slovenia and taught them how to make a rifle type powder suitable for use in small-arms. KIK had not produced propellant powders for some years. The plant had been part of a state owned munnitions factory. Producing powder mainly for use in grenades and land mines. So GOEX had to teach the plant what was required in a small-arms powder acceptable on the U.S. market.
Essentially, the KIK produced powder was made to specifications laid down by GOEX. The difference being that KIK used a commercial alder wood charcoal produced in Bosnia or one of the other Baltic countries.

3Fg powders.

GOEX 3Fg, Date Code 99JY20C
Trace on a 20 mesh screen.
70.8% retained on a 30 mesh screen.
26.2% retained on a 40 mesh screen.
3.0% thru the 40 mesh screen.

KIK 3Fg, Lot 00.04
Trace on a 20 mesh screen.
14.4% retained on a 30 mesh screen.
42.6% retained on a 40 mesh screen.
43.0% thru the 40 mesh screen.

Both of these powders are 3Fg within the screen size range for 3F powder. But compared to GOEX the KIK was extremely fine.
Compared to GOEX produced at the same time the KIK was exceptionally fast. But being so fine it was very hard on patches during shooting.

Whenever a powder plant has to rebuild their corning mill you may expect to see some difference in grain size within the grain size range.

 

[Rebel]

Welcome to the forum. Haven't heard from you in quite a spell. Be nice to hear from someone that actually know what they are talking about. :grin:

 

[Mad Monk]

Rebel,

I have not done much shooting in the past two years. Eyes got to the point where the chronograph was in serious danger only 15 feet from the muzzle. Had cataract surgery on the left eye earlier this month and the right eye gets done next month. From what I was promised I should be able to go back to target shooting once both eyes are done.
Checked the right eye with the ml rifle sights the other day. Looks real clear and sharp.

 

[Rebel]

Glad to hear that you are getting the eye problems fixed. Nice to see you here. Nice bunch of folks here who will appreciate your knowledge of powders. Take care.

 

[Old Ironsights]

Old Ironsights,

3Fg powders.

GOEX 3Fg, Date Code 99JY20C
Trace on a 20 mesh screen.
70.8% retained on a 30 mesh screen.
26.2% retained on a 40 mesh screen.
3.0% thru the 40 mesh screen.

KIK 3Fg, Lot 00.04
Trace on a 20 mesh screen.
14.4% retained on a 30 mesh screen.
42.6% retained on a 40 mesh screen.
43.0% thru the 40 mesh screen.

Both of these powders are 3Fg within the screen size range for 3F powder. But compared to GOEX the KIK was extremely fine.
Compared to GOEX produced at the same time the KIK was exceptionally fast. But being so fine it was very hard on patches during shooting.

That's really interesting because in my test it is almost the reverse (using a 30 mesh) with KIK retaining more than Goex. Both of the below measurements came from New 1-lb cans (One oz was pulled before screening)

KIK 7.3 oz 3F, 9.0 oz 4F/Fines (7.3+9.0+1 = 17.3oz )

Goex (Red can) 4.9 oz 3F and 10.7 oz 4F/Fines !!! (4.9+10.7+1 = 16.6oz)

Anyway, back to the original question:

What grain-size would you use as a practical/safe cut-off between 3F & 4F?

 

[Mad Monk]

Old Ironsights,

The accepted idea in BP shooting is that one never uses 4F as a main charge. So the idea is that you can safely use 3F but not 4F. Nothing about fine lots of 3F approaching the properties of 3F.

There were two shipments of KIK into the U.S. The first was the May 2000 shipment to GOEX. Then nothing until Nov. 2004 as far as propellant powder goes. This second container did not go to GOEX. It went to one of GOEX's master distributors. I have not looked at any samples of the second shipment.

After I had looked at the KIK in 2000 I had commented on message boards that the powder was a bit fine in grain size compared to what we were normally using at that time.
That first container of KIK was low in density. Loading density was around 0.90 g/cc while GOEX was around 1.00 to 1.03 g/cc. The low density was the result of poor polishing. This cost the powder as far as accuracy went. You would get 1 or 2 fliers in a 5 shot string because of the low density/poor polish. I have no idea if they corrected the two deficiencies for the Nov. 2004 shipment of 29,414 pounds.
I did not want to lay out the money for a case just to look at grain sizing and grain density.

If you are picky about the fines in GOEX 3Fg you might want to look at GOEX Cowboy Powder. It is basically 3Fg with the fines removed.
The information they released on this powder simply relates to bp cartridges. Being produced for use in bp cases up to 40 grains for use in pistols in Cowboy Action Shooting. Worked very well in ml rifles for me. Simply saved me from screening 3F with a 40 mesh screen to remove unwanted undesirable fines.
It would be nice if the industry changed the 3F grain size range to pass 20 mesh, stop 40 mesh. In a .45 patched ball rifle it is no big deal but in a .50 the fines can take a toll on patches.

 

[Old Ironsights]

Thanks Monk.

I think I'm going to get a 40 mesh and use it as a Hold instead of the 30 mesh I have now.

Should increase my 3F yeild and still leave me plenty of 4F... :winking: