Factory Loaded With Extruded Powder

[jdmick]

Just a curiosity question. Has anyone run across a factory load that uses an extruded powder? All the various rounds I've checked all use some form of ball powder, even the "premium" ones.

[rn22723]

I am confident that Fed Gold Medal Match 308 is loaded with RL 15, and before that it was IMR 4064. I know that M118LR is spec'ed for RL 15, and I know M852 was spec'ed for IMR 4895.

I do not pull factory ammo, apart to look at the powder. It really serves no purpose because it is a non-canister grade of powder, and it would be a crap shoot to try and guess which powder it is.

[mrawesome22]

If it were not for factory ammuntion ball powder would not be made. It's very temperature sensitive, but it goes through a powder measure great. It contains nitroglycerin. I think LOL.

[BillCA]

Almost all modern nitrocellulose "gun powders" contain some amount of nitroglycerin or nitrate compounds that are close relatives.

As to extruded bar powders - these are most commonly used in rifle calibers for their longer burn time and generally lower temperatures. They are a pain to measure without a trickler too.

[jdmick]

It was the supposed temp sensitivity of ball powder that made me check some of my "premium" ammo. Here in Minnesota the temps during deer hunting can range from 60 degrees to below zero so that could be a consideration. Now that I have a chronometer I plan on testing the validity of those claims. I was surprised to read a while ago that the factories use volumetric metering. I can understand them using ball since any gains from temperature stability of extruded could be negated by inconsistent metering. One more reason I'm sure my wife will understand for handloading.

[singleshot]

Many use extruded or "stick" powders and it is true that volumetric metering is standard.

The factories have several "qualfied" powders for almost every load and their choice is often based on economics. Their primary goal is to make pressure, velocity and (sometimes) accuracy standards they have established at the lowest cost. While you and I think nothing about a powder that needs a few tenths of a grain more than another when you think it terms of tens of thousands of rounds that few tenths adds up to real money.

Only ATK (Federal and CCI/Speer) actually owns a powder manufacturing facility (Alliant) so they buy on the open market from both domestic and overseas sources. As long as the powder meets the requirement price rules.

I think it is true that we are seeing more ball type powders because the manufacturing has really improved and they can be much more versatile.

[amamnn]

Just to correct a couple of misconceptions that I used to have too. All modern smokless powder is extruded as part of the manufacturing process. The powders most often referred to as extruded are stick or cylinder powder.

http://en.wikipedia.org/wiki/Smokeless_powder

Ball powders as a group are not any more sensitve to environmental variations than any other powders. Two of the most popular powders used by those who reload for benchrest competition are H-335 and Vihtavuori's 300 series. Both are ball powders and well appreciated for their consistency over a wide range of temerature and humidity.

[Unclenick]

Double-base powders have both nitrocellulose and nitroglycerine. Single-base powders only have nitrocellulose. IMR rifle powders are the most common example of the latter. The Vihtavuorin N100 and N300 series are both single-base. Their N500 series is double-base, the nitroglycerine addition helping increase the total energy content of a grain of the powder. The N300 series is differentiated from the N100 series by being porous, which increases its burning rate. It is not spherical, but in the words of the Vihtavuori manual is, "cylindrical, either non-perforated or single-perforated" (hole through the middle of the grain). In other words, it is a stick powder, even though the sticks are small and about as short as they are wide (in the case of N310, the only one I had on hand to look at).

Spherical powder is not formed by extrusion. Not even if the Wikipedia says so (I haven't looked). (Keep in mind that Wikipedia entries are authored by whomsoever chooses to write them, a choice which is sometimes governed more by ego gratification than by expertise; the readers are invited to edit entries, so a all kinds of errors are possible.) Hatcher's Notebook has a description of the process. Basically, nitrocellulose is reduced to a slurry with chalk and water in a hammer mill. Chalk is added to neutralize nitric acid radicals formed by natural decay of nitrocellulose. The slurry is put into a chamber called a "still" and a solvent, like ethyl acetate, is injected to dissolve and emulsify the nitrocellulose into a plastic lacquer. Diphenylamine is also added to discourage future breakdown. Motorized paddles are then used to beat the emulsion into little globules that eventually become the grains. A "protective colloid" agent is put in to keep these little micro lava-lamp blobs from recombining into big blobs. Heat drives the solvent out (which is undoubtedly recovered for re-use; hence, "still"). Voila! Spherical grains, ready to be dried and treated with burning rate control agents and graphite.

Commercial ammunition makers use volumetric dispensing the same as pill makers do, and for the same reason. Nobody knows how to weigh charges fast enough to feed a high speed commercial loading machine. When a volumetric measure meters well, this is actually an advantage in that it will keep the total charge energy more consistent should the powder density change due to picking up humidity from the air. This is one reason many benchrest shooters prefer a precision measure to weighing. Develop the load with the measure, then stick with that measure setting. Given that charges are always specified in weight, I find it hard to believe this typically makes much difference, nor that it could make enough to cause a pressure hazard to appear in a load that was once safe. But you know benchresters; picky, picky, picky. A tenth of a grain here, a tenth of a grain there, and pretty soon it adds up to two tenths of a grain.

Nick

[singleshot]

First... "Ball" is Winchester's trademark "Spherical" is Hodgdon's for exactly the same stuff. Hodgdon buys their powder from the same place Winchester does (I know it's more complicated than that )

Ball or Spherical powder does begin by being extruded and cut in exactly the same way as stick powder. The "balls" are then formed by pumping the powder in an aqueous slurry through a piping setup with lots of 180 degree turns. As it goes around those corners the grains are rounded. Near the end of the process the grains may be "flattened" in a roller to control surface area and burn rate.

[Dave Haven]

First... "Ball" is Winchester's trademark "Spherical" is Hodgdon's for exactly the same stuff. Hodgdon buys their powder from the same place Winchester does (I know it's more complicated than that )

And Winchester powder is now marketed by Hodgdon.

[cheygriz]

If it weren't for "factory ammo" extruded powder would no longer be made.

Seriously, I started out reloading in 1965, and all of my rifle loads used extruded powder. By 1980, all of my rifle loads used ball powder, and still do.

I've never found anything extruded powder would do that ball powder didn't do just as well, and ball powder isn't a "Royal P.I.T.A." like etruded powder is.

[mrawesome22]

I still don't get why people think stick powder is a P.I.T.A.? What's so hard about it? And if ball powder is just as insensitive to hot and cold as stick powder, how come Hodgdon doesn't have "Extreme" ball powders?

[CHAINSAW]

I agree with Cheygriz on this subject, in the fact that every load I now use is loaded with ball type propellants, unless I can't even come close to finding what I want.

My RCBS Uni-flow seems to be at it's best with ball type propellants and I have stuck with it.

I keep AA#2, H110, WC846, BLC-2, W748, H414, WC872, and a little H380 on hand. I have a buddy whom I help out and he uses some H4831 that I store for him.

I really like using the ball type propellants.

[jdmick]

Nick, it sounds like your about ready to start manufacturing your own powder.

[brickeyee]

Well into the 1980s the Radford Army Ammunition plant was still re-processing WW2 cannon powder (~30% nitrocellulose) to make both small arms and rocket solid propellants.
The old stuff was stored under water. They may have finally run out.
The actual manufacture of the nitrocellulose from scratch is the most dangerous part of the whole process (heat is realeased as the cellulose is reacted and the process must be cooled and controlled carefully). Once you are past that step things get a lot safer, but in the early 1980s an explosion at the plant killed a truck driver, demolished the truck, and made a decent crater in the road as cakes of nitrocellulose were moved from one process building to another and detonated.
The blast was heard a couple mountain ridges away in Blacksburg at Virginia Tech as a low rumble.

[amamnn]

For what it is worth here are some observations I have made and some that have been related to me by other match shooters.

I'm not sure how much opportunity the "average" reloader has to really experiment with loading in the winter and to compare it whith what he loaded in the summer. Before this post I went back over load records I keep dating back to 2001. Anything before that is not on the computer.

Around here we get to shoot in the kind of weather extremes that Hodgon likes to talk about when they advertise their "Extreme" powders. I've used two of what they are now calling extreme powders, Varget and H4350, and found them to be no more, and in one case less insensitive to temperature and humidity changes than other powders. When you load and shoot 300+ rounds per week for practice and match you can't help but get a some idea of what works and how. I don't load that much on a weekly basis anymore, but I get load a lot, though not as regularly as that and I talk to the guys who regularly beat me at matches to try to get any advantage I can.

I like and use H4350, but found it to be no better or worse environmentwise than some other powders I've used, including RL-15 and W-760. There are not a lot of other shooters using 4350 in match loads here, so my data and impressions of that is stricly my own. There was a spike of interest here in Varget for small bore, but one winter pretty well took care of that. I have seen posts by people who think Varget is the greatest and I am sure it works for them. Most of the people I know here went back to H335 or Vihtavuori N-133 or 135 and still have 2/3 full cans of varget around somewhere, as did I until I gave it away.

While not all the complaints about the Varget had to do with temperature and humidity considerations it was one element many of us found to be a problem, especially those who load at the match. This is not to say that adjustments do not need to be made in loads to be used in cold, wet weather with the other powders mentioned. However, there is only so much time you can profitably fool around with a powder before you dicard it, and some powders just seem to be inconsistent in density from the start. For some of us, in some cases, it may be a matter of preferring the devil you know.