Double powder charge

[Kenk]

Have any of you experienced a double powder charge (firing one) or know anyone that has? Personally, I hand weigh each charge individually, as well as hold a bright light over my charged loads prior to setting the bullets to Verify nothing looks odd.  Regardless of my extreme analness, It is still a concern
Thanks

Ken

[Graybeard]

A guy I knew, manager of a gun store, blew up a Glock with an over charged load. Luckily he wasn't hurt, but the Glock was toast. I knew another guy that had his 1911 race gun let go just below the ejection port down to the rail. That one was a .40 and didn't sound any louder than his previous shots. Still not sure what happened there. The gun had many 10s of thousands of rounds through it and had been rebuilt a couple of times.

I tend to stick with powders that would over flow if double charged. I've seen more squibs from other people's reloads. Equally as dangerous if the barrel isn't checked for a stuck bullet.

A friend of mine badly bulged the barrel of a Just Right Carbine by not realizing he fired a squib that went halfway down the barrel and firing another round. It didn't burst and surprisingly JRC fixed it for free.

[Kenk]

Yep, that is one of the reasons I like Blue Dot so much, very easy to spot a double charge

[sqlbullet]

I have never done it.

While getting my bearings on non-canister powder I have had some excitement.  Blown primers and in one case a case head that ruptured, killing an extractor in an AR-15.  I have become significantly more conservative when dealing with powder that starts "WC" and comes in 8lb white jugs.

I can't imagine a double charge...

[The_Shadow]

Knock on wood no double charges here, however I did have a case rupture with a tiny 380ACP.  This was a combination of 4 things.

First; was I was working with a heavy and long bullet, Lyman Devastator 125 grain cast HP which is based on a 147 grain with the hollow point reducing the weight to 125.

Second; working with a powder (AutoComp) I wasn't very familiar with but based on other loadings with lighter bullets.  I started at a level that was too much.  There are no loads listed for this bullet weight or length for 380ACP and the case capacity is very small, so the margin of the error is very small as well.

Third; I was using a used cases that I was unfamiliar with that blew out.  This casing design had the head area deeper than the primer flash hole.  This turned out to make the head area thinner leading to its failure.

Fourth; my first round I tested was pushing this bullet at 1037 fps from the tiny Ruger LCP 380.  Tried as I might I wasn't able to locate the fired brass for inspection.  I later found that brass PPU which had a significant bulge.  Fired from the 7 yard line I found the brass on the 15 yard line.  Had I found it I would never shot the second cartridge that did 1038 fps that blew out.  This pushed the remaining cartridge, magazine spring and base plate out of the magazine tube.  Further inspection did reveal a tiny hairline crack on the polymer frame.  Ruger replaced it for free, so Kudos to great company!

Lesson here is trying to work a load at a unknown powder level has risk and it can bite you and your gun.  It is also the reason we say work up a load from a lower powder charge a little at a time...

With all of that behind me, I did work to a acceptable loading for this 125 grain bullet which makes 815 fps from this short barrel pistol.

[sqlbullet]

That sounds like the comedy of errors I had:

Heavy for cartridge bullets?  Check!

Unfamiliar powder with limited/implied load data? Check!

Unfamiliar cases that vary in either quality or water capacity from what limited data I had?  Check!

Failure to recognize signs that I was in dangerous waters in the first shot or two, that were evident after the fact?  Check!

Yep.

There are lots of articles in the software testing world that deal with the fact that we just don't see the obvious when we are testing....There are built in bias' against this.

and this is why it is so stressed that we stay with book data.

[Kenk]

And lastly, analness is always your friend : )

[Trapper6L]

When I start to consider what I'm going to load for powder. I always look for a powder that gives me something close to an 80% loading density. Can't have a 160% of a powder in a case and not notice it. I won't load powders like Bullseye for that exact reason. I've found over the decades of stuffing ammo best accuracy is usually with powders that would be labelled medium burn rates with 70-80% loading density. They're not always the highest velocity but I'm old school. Doesn't matter how fast the bullet can miss the target.

Two schools of thought on loading powder. When I first started reloading back in the early 70's, I weighed every round and it had to be EXACT, down to the kernel of powder. Then I ran onto a gunsmith, actually an uncle of a neighbor, that had on the back wall of his shop, a target. The target was probably 5ft square. I asked about it as it appeared to have a single hole in it. It was a group he shot in Illinois back in the 1950's using a 308 Norma Magnum. The distance....1000yds. He described the ideal shooting conditions- early, still morning with temps in the 50's and low humidity. The target was witnessed by 3 people. Mr Kline, of Kline's Gunshop, was the shooter and reloader. He said NEVER weigh a charge as it won't be consistent. Variables such as humidity, temperature, and barometric pressure  will change slightly the actual charge. He claimed the only way to reload was in a room with constant temperatures and humidity, and use a good powder measure. While I weigh my charges when developing load, I use a powder measure to actually throw the powder and note the micrometer position so I can go right back to it. I've shot lots of one hole groups since including in the infamous Houston Warehouse with a Remington 40X in 30/338 mag sailing 190gr custom Winchester bullets. I also shot an unlimited class .261x47 TNT rifle that was a one holer. All charges thrown in pill bottles as you reload the same 5 cases every shooting round. FWIW, there is no case resizing with a TNT rifle. Just punch the primer, push in another one, throw in the powder from the pill bottle, seat the bullet with a hand seater. Not saying my way is the only way but that's the way factory ammo is loaded including match ammo. Bench shooters here generally are volume loaders, not weight loaders. If you have a GOOD powder measure, might give it a try.

[gadabout]

Years ago I was shooting 9mm and decided to go to 147g bullets. The rounds seemed very low on recoil and I worked up to 3 or 4 grains over book data. With a non supported ramp I blew out the case near the extractor band and blew brass all over my face with minor cuts. The range people checked the gun and even shot the rest of my reloads that were overloaded. Go figure. I now triple check everything.  Craig

[Sobrbiker]

If you're worried about a double charge, and wanna load 180+ bullets in your 10mm, I would recommend AA#9. Good velocity, great accuracy, and no way to overcharge a case without knowing it.

[Kenk]

Thanks Sobrbiker,
It's not so much a worry, but something in the back of my mind that comes up now and then. As with anything potentially dangerous, consistency and focus are key to avoiding trouble

[The_Shadow]

When I start to consider what I'm going to load for powder. I always look for a powder that gives me something close to an 80% loading density. Can't have a 160% of a powder in a case and not notice it. I won't load powders like Bullseye for that exact reason. I've found over the decades of stuffing ammo best accuracy is usually with powders that would be labelled medium burn rates with 70-80% loading density. They're not always the highest velocity but I'm old school. Doesn't matter how fast the bullet can miss the target.

Two schools of thought on loading powder. When I first started reloading back in the early 70's, I weighed every round and it had to be EXACT, down to the kernel of powder. Then I ran onto a gunsmith, actually an uncle of a neighbor, that had on the back wall of his shop, a target. The target was probably 5ft square. I asked about it as it appeared to have a single hole in it. It was a group he shot in Illinois back in the 1950's using a 308 Norma Magnum. The distance....1000yds. He described the ideal shooting conditions- early, still morning with temps in the 50's and low humidity. The target was witnessed by 3 people. Mr Kline, of Kline's Gunshop, was the shooter and reloader. He said NEVER weigh a charge as it won't be consistent. Variables such as humidity, temperature, and barometric pressure  will change slightly the actual charge. He claimed the only way to reload was in a room with constant temperatures and humidity, and use a good powder measure. While I weigh my charges when developing load, I use a powder measure to actually throw the powder and note the micrometer position so I can go right back to it. I've shot lots of one hole groups since including in the infamous Houston Warehouse with a Remington 40X in 30/338 mag sailing 190gr custom Winchester bullets. I also shot an unlimited class .261x47 TNT rifle that was a one holer. All charges thrown in pill bottles as you reload the same 5 cases every shooting round. FWIW, there is no case resizing with a TNT rifle. Just punch the primer, push in another one, throw in the powder from the pill bottle, seat the bullet with a hand seater. Not saying my way is the only way but that's the way factory ammo is loaded including match ammo. Bench shooters here generally are volume loaders, not weight loaders. If you have a GOOD powder measure, might give it a try.

Trapper, here is a little insight and my thoughts about the drop method.  When you are dropping a charge for a big rifle cartridge a tenth or two is not as significant as in a smaller cartridge such as 9mm or 380.  Those slower denser powders provide a lot of gas to shove the projectile and the differences are also small.  But when casing sizes are smaller differences can show in pressure quicker however they are usually shot a shorter distances so accuracy may not show as much as a result.

I know that there are shooters that are utilizing scientific scales, verifying their loads to 1/100th of a grain for competition at long range events.  Powder charge weights are one of the most controllable factors other than sorting brass casings and bullet weights.

I have always handweighed my loads each and every one to a balanced scale and when shooting at 100 yard distance with pistols it produced greater accuracy for me.  It also provided very good accuracy with my rifles at hunting distances.  None of my rifles are what I'd call competition rifles.  Not being a long distance competition shooter, I still take advantage of the control with the propellant for safety and assurance of knowing exactly what's inside!  In the words of Dirty Harry, "A man's got to know his limitations!"

[Kenk]

Plus for me, reloading is kind of therapeutic, my wife knits and I make bullets, Lol. The extra time taken to hand weigh / verify each rd isn't a big deal

[sqlbullet]

Volume versus weight is an interesting question.

In baking it is huge.  You will find most recipes at my home have the flour and sugar listed by weight not volume as there can be significant differences of mass by volume.  Humidity will impact flour weight, but not as much as compression or fluffing can alter it's volume.  Also interesting to note the placement of the word "sifted" in recipes.  2 cups sifted flour and 2 cups flour sifted are not the same thing.  The first is an attempt to normalize density of the flour as a control in measurement, while the second is to control the density prior to introducing other ingredients.

I don't know that the density of gun powder varies to the same degree as flour, but given that the dipper methods have very specific rules about how to fill and card the dipper for consistency, it clearly can be an impact.

Humidity, or water content, is another interesting question.  No doubt it does impact ignition negatively, which will explain why some users need magnum primers where others don't.  But, if complete combustion occurs, the water will vaporize and should provide similar expansion ratios as the gunpowder.

Man, I need to retire, be wealthy and have time to just develop data.

[Kenk]

Me too...Absolutely!