Ball Powder reduced loads

[Piet]

I have read that ball powders should not be used for reduced (low pressure) loads.
What is the reason for that?

[Scrounger]

In reduced loads it suffers inconsistent ignition. It requires a higher loading density in order to achieve the burning pressure it needs to be consistent.

[Baron von Trollwhack]

Yet I see the same ball powder listed for US 8mm Mauser low pressure loads and then elsewhere for euro loads at a higher pressure. I do not follow that pressure theory. BvT

[sundog]

Can't talk to reduced ball powder loads with jacketed, but I can with cast in bottle neck rifle loads. Don't. Wanna experiment with click-bang? It's the way to go. There are way too many other powders suited to running reduced loads safely and efficiently.

Just because a load is listed in a manual doesn't mean that it's a good load. My experience with rifle speed ball powders is that to get them to work efficiently they need pressure, more pressure than most reasonable cast loads. That said, it is still possible to come up with some great ball powder loads. Case in point is pushing the 311041 in 30-30 to 2000 fps with surp 844, great load but it is not a reduced load.

[Piet]

I was wondering about using Accurate no. 9 or no 7 . Those are not slow. Do you mean a delayed ignition with click-bang or a catastrophic unorganized sudden fieldstripping of the rifle?

[felix]

Yep, click-bang is definitely SEE territory with any kind of projectile. Never repeat that load under any circumstance. Pull every one of those suckers without hesitation. All it takes is one that does not go poof, or click-bang, to indicate what chemistry gone wild can really do! Just because it is a mild load in a revolter does not mean it will be a mild load in a closed breech. Generated wave actions are completely different. Faster the powder with proper application, the safer the load is. #7 would always be safer than #9 because there is more powder in the case with #9, and thus more energy with #9. ... felix

[sundog]

#9/H108/WC820 are a mainstay for many single shot guys in cases all the way from 32 Miller through and beyond 32-40 and many others with plain base boolits and relatively low muzzle velocities. Done properly it is very safe and accurate, but also rather specialized in this respect. For me it would not really be the ideal choice for other medium to large rifle cases, there are a lot of other powders to choice from.

I would steer way clear of #7, not that it's a bad powder, it's not, just not for rifle. Too many other saner choices. Me? No, there are too many other choices. And another thing, those fast powders are just too easy to double charge.

[Maven]

I think the answer depends on the specific cartridge and ball powder combination rather than something instrinsic to ball powders themselves. E.g., Winchester used to warn reloaders to use W 296 EXACTLY as described in their reloading guide, including bullet & primer. (This may also apply to H110, which is supposedly the same powder.) Moreover, Lyman used to recommend W 748 in the 8mm Mau. with cast bullets (26 or 26.1grs. if I recall), but Winchester did not owing to hang fires: Winchester was right! As for WC 820 (AA #9 burning rate), I've been using it in the .243Win., the .30-06 and metric .30cals., the .45-70, and the .357mag. in what have to be reduced loads, e.g., 14grs. in the .243Win., 17 - 18grs. in the .45-70 and 10.3grs. in the .357mag., with nary a problem and excellent accuracy. In short, SOME ball powders respond very well to SOME cast bullet [weight] - charge - cartridge combinations, others may indeed be risky or even dangerous.

[felix]

Maven, the SEE danger only comes with an ES greater than X, whatever X is. I would suggest 100 fps for a spot-on load, that is, a load with constant powder volume. Vary the powder by a quasi 10 percent in either direction, the X might be an acceptable 200. One way to find out would be to shoot four groups, say 10 rounds each. One at 15 grains, one at 16 grains, one at 17 grains, and one all jumbled up. Shoot 30 round groups to find a your valid statistical measure (Student's t). ... felix

[Scrounger]

I used to shoot WC 820 on the .30-06. It was accurate but it had bad habits. At that low density loading, a lot of the powder did not burn and it tended to migrate into places you didn't want it, like the ejector on the bolt as well as inside the bolt and into the locking lug recesses in the receiver. Having to completely disassemble the rifle every time you use it is reason enough not to use that powder in that application.

[Maven]

Felix & Scrounger, Thanks for reminding me about high extreme spreads. Oddly (and thankfully) enough I haven't experienced this with WC 820, but could predictably count on the very slow, extruded IMR 5010 to -> high ES's in my .30cals. (metrics too) even with heavy CB's, a filler and mag. primers. As for WC 820's "cleanliness," I use 18.5 - 20.5grs. in my '06 and find it to be exceptionally clean burning with no unburned powder accumulation anywhere. Now, if you want to see lots of unburned powder in all the wrong places, try WC 860 or IMR 5010!

[Larry Gibson]

Ball powders have a deterent on them that controls the burning rate. Thus we see ball powders in the fast, medium and slow burning rates. It is simply that the medium and slow burning powders have a more burn resistant deterent on them, i.e. it is the deterent that controls the burning rate. These deterents make ignition and burning inconsistant without a certain loading density and pressure level. If you use a reduced load of medium to slow burning ball powder for cast bullets you will have ignition difficulties. These may manifest themselves as very large ES/SD, "click-bang", click-nothing and posibly SEE. None of those are condusive to good accuracy or good shooting and in fact may be dangerous.

Note; cartridges such as the .30 Carbine, 7.62x39 and 30-30 (and a couple others) that can push equal weight cast bullets to the velocity/pressure of J bullets can use the same ball powders as the loading density and pressures are the same. These are not reduced loads such as trying a 30 gr load of BLC2 under a 311291 in an '06 (please don't try it).

The use of the fast burning ball powders generally works for cast bullets from pistol loads up through rifle loads up through 1800 fps.

The caution should read; "medium and slow buring ball powders, including H110 and 296, should not be used for reduced (low pressure) loads." The amount of deterent on these type ball powders is the reason why.

Larry Gibson

[hydraulic]

I've been using 22 grs. of AA2230 under 311413 in .30-06. Please comment.

[Pavogrande]

Oh dear, I have been using 30 to 33 grains of ball c in 06 and 30/40 under 311291 and H&G 99 since the '50s --

[Scrounger]

Our differences, if differences they are, probably stems from our definition of "low pressure". I think of low pressure loads having an effect on ball powder as loads of less than 25,000 CUP. In loads of 30,000 to 40,000 or more, like for the .30-30, I wouldn't anticipate any problems. Common sense, guys, if it's a factory published load, it's probably OK.

[Larry Gibson]

Hydraulic

AA2230 is relativiely easy to ignite and your pressure level probably gives consistant ignition. Have you chronographed that load yet? If so what is the ES of a 5 or 10 shot string?

Pavogrande

Your load of BLC2 also is obviously of sufficient pressure for consistant ignition. Same question to you about chronographing.

As I mentioned, "reduced (low pressure) loads", and Scrounger reiterated it is with low pressure reduced loads that ignition becomes the problem. Apparently neither of you have loads in that "low pressure" area.

Larry Gibson

[hydraulic]

Thanks for the response, Larry. I had, regretably, given up on that load for safety's sake. It is my most accurate load and I had laid in a supply of AA 2230 & magnum primers that would last me as long as I'll be able to shoot. I'm 70. I replaced the AA 2230 with IMR 3031 and have been developing a load with that. I am going to order a new Chrony, (shot my old one two years ago), and if the ES's are not wildly erratic, maybe I can use my old load. By the way, this is used in a pre-64 Winchester M70 featherweight made the same year I graduated from high school; 1955. This rifle is responsible for the precipitant decline in the Nebraska coyote population in recent years.

[JeffinNZ]

I think there are two dimensions in this discussion when we talk about 'reduced':

1) load density
2) operating pressure

For example in my .303 Pygmy I shoot 23gr of W748 under s 220gr bullet for 1500fps. This is near 100% load density but the pressures are (in theory) in the mid 20K range. Must be as the alloy is only 10 BHN and shoots like a house on fire.

Soooooo, W748 will shoot well at lower than normal pressure but with a near full case. How it would go with 40-50% load density I can't say.

[budman46]

30 years ago i used a reduced load of ww748 in a .30-30 contender with a 170 gr gc bullet; the load was determined by using 80% of the powder charge suitable for a 170 gr j-bullet.

i'd fired 50 or 60 rounds and was pleased with the performance until one load went ka-boom! the contender had to be dismantled to get it open...the rimfire firing pin was gone and the barrel's locking lug had a big chunk missing. i'm not exactly sure what happened...perhaps the primer impulse drove the bullet into the forcing cone where it stopped until the powder finally ignited, the bullet now acted as a barrel obstruction...but i'm thankful the contender held. later i learned of the warning regarding downloading certain ball powders...

budman46

ps. i sent the gun to t/c with a letter of explanation asking them to repair it and send me a bill...t/c replaced the frame and repaired the barrel at no charge with a letter stating they were sorry for my inconvenience.