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View Full Version : Different Powders (Ex. H110 vs. Accurate No. 9) and potential for mistakes.



Mark Ducati
11-11-2011, 11:36 AM
Last night, I primed and belled the mouth of all of my new Starline brass... so, I pull my scale out to load just a few rounds.

For 50AE 300gr bullet, I use 33.5gr of H110 powder... so, I pull my balance beam scale out to zero it and it was still set from last week's reloading batch... only the front weight was on 40! Indicating I loaded my cases with 43.5gr of H110 powder! 10 grains of powder too much :(

My first thought was crap, I'm going to blow my gun up... but yet, I was sooooooo careful weighing the powder (sober, no kids, no distractions). I couldn't believe I made that mistake, so I randomly pulled a few bullets out of the 200 rounds I loaded and reweighed the powder... yep, I was at 33.5 grains. I did load my cases correctly. I think putting the scale up, the front weight moved from 30 to 40 grains.

So, then I weighed out an oversized load of powder to 43.5 grains just to see what it looked like... normally, the 33.5 grains of H110 fills the case about 3/4 full... but 43.5 grains of powder filled the case about 7/8 full... IF I had overweighed the powder, there wouldn't have been any room to seat the bullet.

So, I guess the point of my post is that different powders require different grains of powder amount... for example, for my 50AE 300gr speer GDHP bullet: I need 33.5gr of H110 and Accurate No. 9 powder recommends 23.5 grains of powder...

If I had been using Accurate No. 9 initially and put 10 extra grains of powder in, the bullet would have still seated and I may not have known/noticed...

This H110 may require more powder for the load, but visually, there's no way I could make that kind of mistake nor get the bullet to seat...

So, for my particular batch of 50AE with H110 powder, its a "safer" powder for a noob like me to use.

I really understand now why Schuetz recommended absolutely no distractions when loading... no drinking, no TV, no kids, no radio... just concentrate on the job at hand. It's way too easy to make a simple mistake.

O.S.O.K.
11-12-2011, 01:22 PM
Yep. You need to focus when loading. I zero the scale before puting the cover on it too.

And it's generally a good idea to select a propellant that gives near 100% fill for a given caliber.

But handgun rounds generally aren't at 100% - more like 50 to 75%. The older ones that started out as black powder rounds are the "worst" when it comes to fill rates.

Schuetzenman
11-12-2011, 08:33 PM
It's called bulk density Mark. H110 and A No.9 are both ball powders and look identical nearly, but either their density or their burn rates or maybe both properties are different.

I've read and heard that many powders that look similar are the same base powder. They burn differently because different retardants are added to slow down the burn rates and therefore change their relative pressure curves. I have had the privelage to visit Accurate Powders back in 1993 or 94 and get a tour by their Chief Ballistician, a man named Fallen I think it was.

Anyway they test each lot of powder in a pressure gun that can transmit the strain information to a computer showing the burn and pressure peak rates. Any lot can have some varianc, some are very fast, some slower. They can be blended to put the powder's burn curve in the proper pressure vs. time range. This is how powder companies go about assuring consistant results lot to lot.

From my point of view, pistol powders are a lot less potentially hazardous when loaded in than rifle powders and rounds. Rifle cartridges hit some big pressure numbers. Of course using pistol powder in a rifle round would be the worst case scenario for screwing up.

Believe it or not my first reloading was for .45 ACP, and .357 magnum. Being young (teenager) I wanted to be able to load as many rounds as possible for my money so I bought Bullseye Powder. It's very fast, about like A No. 2 powder. You load 3.5 to 5 gr. charges. With 7000 grs. per pound that's a lot of rounds per pound. I still managed to load safely. I also found out Bullseye wasn't the best choice for .45 Auto, but worked just fine for the .357.