Under max load, primers flat
- Thread starter Greg S
- Start date
Not at all. Do the above experiment and you will see it is more than semantics.
Take care
Bob
Nitrocellulose and nitroglycerin are explosives, ergo smokeless powder is an explosive which is placed in an admixture such that it deflagrates rather than detonates.
"Suugestions (sic)" that it is not "are nothing more than internet noise."
See? I can make silly dismissive statements too!
-M
Hydrogen is an explosive gas and Oxygen supports combustion.Nitrocellulose and nitroglycerin are explosives, ergo smokeless powder is an explosive which is placed in an admixture such that it deflagrates rather than detonates.
"Suugestions (sic)" that it is not "are nothing more than internet noise."
See? I can make silly dismissive statements too!
-M
Water is a combination of the 2 and cannot cause a fire or explosion.
Water on the other hand can put out most fires quite effectively.
See what I'm getting at?
thump rrr, I have been told by people that should know, that if a fire is hot enough or the chemicals burning are correct, water sprayed on them will separate into their separate molecules and then burn.
You both have the right idea though, and you both are splitting hairs.
Smokeless powder granules are coated to to give them a "burn rate". They are usually coated with graphite and a binder as well. This stops them from "exploding".
That doesn't mean that they are inert. Far from it. Doc M is right, so are you. The thing is, none of them are a problem until they are broken down to their dangerous levels. That's what saves us in court.
You both have the right idea though, and you both are splitting hairs.
Smokeless powder granules are coated to to give them a "burn rate". They are usually coated with graphite and a binder as well. This stops them from "exploding".
That doesn't mean that they are inert. Far from it. Doc M is right, so are you. The thing is, none of them are a problem until they are broken down to their dangerous levels. That's what saves us in court.
Excellent post, Gerald.
Just some comments on the original post. Flattening of primers is not considered a very good indicator of pressure in the cartridge. One person may call a primer overly flat, while another may say it is normal, while a third may say it looks to him/her like a lighter load. Also, several have pointed out that primers vary a lot and a load that flattens brand A, may look normal with brand B.
If the bolt is easy to open, with no extra pressure felt to start the case out, you likely have a normal, or under normal pressure load. A modern, meaning any rifle made after WW One, bolt action rifle has a lot of lea way safety. This is not to say that over loading is not dangerous, but if the bolt is not sticking on loads, another grain or so of powder is not going to, "blow it up in my face."
I will bet that most of us who have been reloading for a time, have at some time, had to bang the bolt handle to get an empty case free of the chamber. Heck, I have even had to use a chunk of 2x4 with a very solid whump, to break the bolt free on a brand new magnum rifle with a Norma factory load. Cleaning of the chamber, to allow the brass a better surface for gripping the chamber walls, solved the problem.
And speaking of flattened primers, I still have a the empty from a Norma factory load 7 x 61 from the 1960s, fired at the time in a new Schultz and Larson rifle. That primer is flat-flat. Not an over load, just a factory loaded cartridge.
Just some comments on the original post. Flattening of primers is not considered a very good indicator of pressure in the cartridge. One person may call a primer overly flat, while another may say it is normal, while a third may say it looks to him/her like a lighter load. Also, several have pointed out that primers vary a lot and a load that flattens brand A, may look normal with brand B.
If the bolt is easy to open, with no extra pressure felt to start the case out, you likely have a normal, or under normal pressure load. A modern, meaning any rifle made after WW One, bolt action rifle has a lot of lea way safety. This is not to say that over loading is not dangerous, but if the bolt is not sticking on loads, another grain or so of powder is not going to, "blow it up in my face."
I will bet that most of us who have been reloading for a time, have at some time, had to bang the bolt handle to get an empty case free of the chamber. Heck, I have even had to use a chunk of 2x4 with a very solid whump, to break the bolt free on a brand new magnum rifle with a Norma factory load. Cleaning of the chamber, to allow the brass a better surface for gripping the chamber walls, solved the problem.
And speaking of flattened primers, I still have a the empty from a Norma factory load 7 x 61 from the 1960s, fired at the time in a new Schultz and Larson rifle. That primer is flat-flat. Not an over load, just a factory loaded cartridge.
- Location
- The Conservative part of Ontario
Modern smokeless powders contain retardant materials.
Bruce Hogdon went to court many years ago in the US to get his powder declared a flammable solid so he could ship it more cheaply. He won.
In Canada, the Liberals have had years of playing with classifications. Lets keep them out of power.
Bruce Hogdon went to court many years ago in the US to get his powder declared a flammable solid so he could ship it more cheaply. He won.
In Canada, the Liberals have had years of playing with classifications. Lets keep them out of power.
Factory loads, loads put up in new brass and loads that have been put up cases that have been sized more than they should have been will show more primer flattening than those in neck sized cases or partially FL sized.
When a cartridge is fired the primer is partially blown out of the case, and expands a bit. When the pressure builds higher, the case is drived back against the bolt face and reseats the primer while swageing it back down. Thats where most of the flattening and the cool looking top hat shape comes from.
On a neck sized case the headspace is close to zero, and the primer doesnt get to intially escape as far. Because of that, the primer doesnt show as much flattening at the same pressure level. You can easily get ejector marks or a sticky bolt long before the primer flattens as much as factory loads.
When a cartridge is fired the primer is partially blown out of the case, and expands a bit. When the pressure builds higher, the case is drived back against the bolt face and reseats the primer while swageing it back down. Thats where most of the flattening and the cool looking top hat shape comes from.
On a neck sized case the headspace is close to zero, and the primer doesnt get to intially escape as far. Because of that, the primer doesnt show as much flattening at the same pressure level. You can easily get ejector marks or a sticky bolt long before the primer flattens as much as factory loads.
Thanks for the replies. One of the posts has a photo of a couple of primers that are a bit flat. Mine are FAR more obviously FLAT than those ones. As far as over or under max and always start low and work up: it seems to me that I have frequently read in this forum and another, to start 2 grains under the max and work up. I went to the Hodgeson website, took their max allowable load for that bullet and calibre, 47.3, and started at 45 grains, a nice round number and a lighter load than the recommended 2 grains under. After the pressure signs I looked in my Speer book and found it to be their max. I still wouldn't expect the max to show pressure signs like that. I'd have expected to have to go greater than max to get signs. Which brings me back to one of my original questions: Can the gun itself cause pressure signs? I note the mention of primer being forced out then back in.
Something new loaders should understand is that maximum velocity doesn't always (I could use the word "Seldom") equates to maximum accuracy in their gun. By working up loads one has an opportunity to find out what load works best in their rifle or handgun.
Too, one wants to remember as brass is reloaded, overtime primer pockets do expand which will account for primers being "flattened" more as less friction is available to retain them. At some point brass has to be discarded simply because the primer pockets are to loose.
For the most part I believe it is best to stay within manual specs. While there are some variations as to min/max listed the differences aren't sufficient IMHO to worry about.
Take Care
Bob
Too, one wants to remember as brass is reloaded, overtime primer pockets do expand which will account for primers being "flattened" more as less friction is available to retain them. At some point brass has to be discarded simply because the primer pockets are to loose.
For the most part I believe it is best to stay within manual specs. While there are some variations as to min/max listed the differences aren't sufficient IMHO to worry about.
Take Care
Bob
Yes it can, with looser headspace being a likely culprit. Put the same load in a neck sized case and it may not show any flattening at all.
I've got a new Steyr Mannlicher that does the same thing with new brass or full length sized cases. If I set the die to just kiss the shoulder the flat primers go away. There's a long chamber on that puppy, but it shoots so embarrassingly well that I'm willing to let it slide.
The maddening part is that a guy will spend so much money on custom barrels, then these factory guns show up and outshoot 3/4s of them.
Did those "people that should know" also tell you that the stork brings newborn babies?
It requires electrolysis to separate water into hydrogen or oxygen.
Take an oxy/acetylene blowtorch which has a flame temp of 6,300F and spray a mist of water over it and tell me if it explodes?
I'll give you a hint. Water boils at 212F.
Try putting water onto a magnesium fire or titanium fire.
Put on your tin-foil hats! The reference to it and videos are now GONE. There was a guy 20-30 years ago that discovered a way to burn water. Water was used as the only fuel AFTER he got the system primed. He had some sort of ceramic ring heated white hot. As it was burning with the supplied fuel he slowly turned on a valve that sprayed water at high pressure into the centre of the ring. That really got a roaring flame. Once this was going he slowly turned off the preheating fuel and the system continued to burn with only the water as the "fuel". His explanation was separation of molecules. It was amazing and has since disappeared. Same as the technology for water injection into a carburetored engine disappeared back in the fifties. It worked too but didn't burn, just turned to steam to give the engine a boost.
Back on subject---I'll get my head space checked. Is there anyway to do it myself? Savage 99F
