New to reloading, but loaded 5 338 win mag 250 grain A-frame bullets. Used RL19. One bullet with 67 grains, one with 68 grains, one with 69 grains, and so forth to determine how high I could go. None of the cases showed any signs of high pressure, except for slightly flattened cases. The 67 grain the primer looked perfect. The 68 has a slightly flattened prime, the next was flattened a little more, and so on. Although the 70 grain, which was the last one I shot, had the most flattened primer, it still wasn't flattened completely filling the primer pocket and there was no crater. When does someone determine the max load for a cartridge? Are these flattenings of these primers just a soft primer, or pressures that are too high? Thanks

Primers usually don't tell the story by themselves. What other, if any, pressure signs did you get? For example, sticky bolt lift. Reading primers can be tough. Also, are these loads within the Swift manual's recommended loads?

LWD

There were no other signs of high pressure. ie no sticky bolt or anything. Also the cases looked fine. I don't have a swift manual, but alliant emailed me with the min and max powder or RL19 for that bullet and caliber. I think 68 or 69 grains was the listed max powder. I only went as high as 70 grains. Maybe I should just stick with 68 grains of powder.

Flattened primers are a sign of high pressure.You might want to reduce the load for better performance from your rifle.If you really want to go that high then consider moving on to a bigger caliber.

How were the primer pockest on each consecutive case?? Looser pockets than the lesser charges means you are running too hot.

You must check all the pressure signs.....like "case head expansion", flattening primers, sticky bolt lift and extraction.....yes a chrony gives some information as well......but in and of itself no single thing tells whether the load is excessive other than expanded primer pockets.

Reload the fired cases and see how securely a new primer seats in the pocket.....if it's loose or obviously less secure than previously you're too hot and need to cut back at least two full grains.....

Reload and try again with a new case! The acid test is inserting new primers.....

I resized and primed the cases. They all seated snuggly. Not sure if that's a word. It's difficult to get a good feel, cause I'm using the priming thing that is built into my RCBS partner press. I might have noticed that the one with the most flattened primer was a bit easier to seat the primer, but it wasn't very noticeable if it was. They diffinately weren't "loose", though. I'm probably better off loading with the 67 grains and being safe. Sound good?

quote:

Originally posted by Ckemp:
I resized and primed the cases. They all seated snuggly. Not sure if that's a word. It's difficult to get a good feel, cause I'm using the priming thing that is built into my RCBS partner press. I might have noticed that the one with the most flattened primer was a bit easier to seat the primer, but it wasn't very noticeable if it was. They diffinately weren't "loose", though. I'm probably better off loading with the 67 grains and being safe. Sound good?

A single fired round per load is not a very good sample size to hang your hat on. I would recommend that you get a hand priming tool ASAP. Priming with a press is Neanderthal.

Now that I am home, I can tell you that the Swift manual lists 68 gr of RL19 as max for a 250 grain A-Frame. So your 70 grains exceeds the max from Swift and the max from Alliant. Usually not good.

So my inclination would be to agree with you and call 68 grains the max.

But remember, velocity isn't the only objective here. Load up and shoot some groups. I generally like to see three, three-shot groups that are consistent before I call a load accurate. If 67 or 68 grains gives an acceptably accurate group, most of us will see little use for exceeding published loads for a bit more speed. Besides, anything that needs shooting with a 250 gr A-Frame isn't going to care if you started it at 2600 or 2700 fps.

However, if you want to really check this, then you need to do what the others have said and reload the same case several times checking for primer pocket expansion by hand seating the primer. You can take enought reloading gear to the range to do it all in one trip if you want.

LWD

First, you have to use more rounds at each step. Statistically, a test of one is not extremely valid. That being said, if that one shows pressure, like the flattened one, then it is statistically significant. It has done this by primer and looser primer pocket. Drop at least a full grain from that load and load in descending order three to five rounds each at either .5 or 1gr increments. The more, the better. This will also permit you to get a feel for each loads accuracy potential. Take one or two other rifles to the range with you, and shoot no more than three rounds at a time with you rifle before shooting the others to permit the barrel to cool. I really like to take a .22LR with me because its cheap to shoot and I can spend five minutes shooting it while my test rifle cools. Kudude

quote:

... take a .22LR with me because its cheap to shoot and I can spend five minutes shooting it while my test rifle cools. Kudude

Now there's an idea! Not sure why I did not think of that.

Can't too much headspace flatten primers some with no other pressure signs?

quote:

Originally posted by Jimmy Barnes:
Can't too much headspace flatten primers some with no other pressure signs?

YES roger

Flatten primers are always an indication of a high pressure but not necessarily an excessive pressure. As others have stated a primer alone does not tell the whole story.

I would like to know what Ckemp meant by flattened primers. If the load in a 338 Win. Mag. is operating at the pressure it was designed for, the primers will be flattened to some extent. If there is still a little rounded edge to the primers and they aren't completely smashed flat and level with the edge of the case, I wouldn't consider them excessively flattened. Shoot a factory load; the primer will be somewhat flattened in it as well.

Other signs on a primer of high pressure would include cratering. Cratering is a slight raised edge around the indentation of the firing pin. A little cratering is OK but is a sign that maximum pressure is being approached. Cratering can also be caused by a firing pin hole that's a little too big.

A pierced primer or primer leak is a definite sign of excessive pressure. Primer pockets that get loose in 2 or 3 reloadings are also a sign of high pressure.

quote:

Originally posted by Grumulkin:
A pierced primer or primer leak is a definite sign of excessive pressure. Primer pockets that get loose in 2 or 3 reloadings are also a sign of high pressure.

Pierced primers or primer leaks can and do occure for a number of reasons other than excessive pressure, as attested just yesterday. roger

"Can't too much headspace flatten primers some with no other pressure signs?"

YES, but .... even so, it doesn't automatically mean there's a problem with the chamber, more commonly it's from incorrect FL sizing which crates slack in the chamber.

Many reloaders - MOST? - carefully follow the instructions to "turn the FL die down until it contacts the shell holder and go a quarter (or half) turn more. That insures that any case so sized will chamber in any standard chamber. But, doing it that way can also size cases several thousanths too much. IF the chamber is on the large size and the die is on the small side of spec.s that WILL size too much!

Sizing so the cases chamber with only slight resistance insures they will be tight enough to prevent primers from backing out and then getting re-seated under pressure and made flat in the process.

This thread is very relevent to me as I am trying to get as much velocity out of my hornet as I can (to get decent accuracy). I get no other pressure signs so have to go on the primer alone. It's easy to keep pressure mild - it's when I get close to the top end that I am no longer sure. My rifle produces cratering long before the rounded edges start to fill out. And then I get one that is flatter than the rest and I wonder whether that was a hotter load or a softer primer. When I get one shot out of the main group at the same time I wonder whether that was the one.

quote:

When does someone determine the max load for a cartridge?

read the manual. approach MAX with caution and dont exceede.

Thanks for all this info. It's nice to know that there is somewhere to go to get this type of info. The books don't cover everything. I'm gonna load a few at the 68 grains and see if I can get decent accuracy and be happy with that. I really don't see a hunt in my future... hopefully I'm wrong... that I will even use this recipe. I have a cow elk tag this december, but my 270 win is much more accurate, so I'll probably use that.

Velocity has little to do with accuracy. Normally you will find your most accurate load somewhere below the maximum listed load in the manual. Going above that load usually destroys your accuracy.

quote:

Originally posted by 303Guy:
This thread is very relevent to me as I am trying to get as much velocity out of my hornet as I can (to get decent accuracy). I get no other pressure signs so have to go on the primer alone. It's easy to keep pressure mild - it's when I get close to the top end that I am no longer sure. My rifle produces cratering long before the rounded edges start to fill out. And then I get one that is flatter than the rest and I wonder whether that was a hotter load or a softer primer. When I get one shot out of the main group at the same time I wonder whether that was the one.

Hey Ckemp, Stare at the top of the Reloading Board for a minute and you will see a "PM" flag flashing. Click on it.

If you do not see the PM Flag, then your "Personal Settings" here at AR are blocking it.

You didn't mention what type of action you were using. Sometimes on certain actions there are extractor marks on the case head if pressure is reaching the max.?

Thanks PaulS. Hodgdon has all the data available on the web. And very good data too, with starting load pressure and max load pressure, for a whole range of powders. But because I have deviated from the 'norm', my objective is to get consistant burn without the benefit of neck tension or crimping. There are no heavier than 55gr bullets listed so I have to work up the normal way. I am trying to find the lowest pressure load that produces the accuracy acceptable to me. That 60gr Hornady SP is surprizingly flat shooting and accurate and hard hitting. I want the 60gr bullet for ferral goat hunting. It gives a higher down range velocity. I have also been able to get good accuracy with Nosler 55gr BT's. Normally a hornet will not stabilize a boat tail with a 1 in 16 twist. I find 55gr Hornady SP's to be a bit flatter shooting but more wind sensitive but harder to get the accuracy. But I am having fun - that's what counts.

quote:

Originally posted by Hot Core:
Hey Ckemp, Stare at the top of the Reloading Board for a minute and you will see a "PM" flag flashing. Click on it.

If you do not see the PM Flag, then your "Personal Settings" here at AR are blocking it.

I don't see a PM flag anywhere. I'll try to change my personal settings to allow it, although I don't remember setting it so that I wouldn't get PM's.

quote:

Originally posted by bartsche:
Flattened primers are always an indication of a high pressure....

not exactly; a low-pressure load with excessive cartridge clearance can do it. the FP drives the case forward, the primer backs out a bit, the whole case is shoved back, and the primer is mildly riveted but still within the pocket, quite flat.

quote:

Originally posted by delloro:

quote:

Originally posted by bartsche:
Flattened primers are always an indication of a high pressure....

THIS WAS NOT MY QUOTE[COLOR:RED]'s message!!! JUST THE OPPOSITE!!!!! GO BACK AND REREAD[/color]

If you are going to quote someone please make sure you know what your doing and capture the intent and meaning of the whole quote.

quote:

Originally posted by Jim C. <><:
"Can't too much head space flatten primers some with no other pressure signs?"

YES, but .... even so, it doesn't automatically mean there's a problem with the chamber, more commonly it's from incorrect FL sizing which crates slack in the chamber.

Many reloaders - MOST? - carefully follow the instructions to "turn the FL die down until it contacts the shell holder and go a quarter (or half) turn more. That insures that any case so sized will chamber in any standard chamber. But, doing it that way can also size cases several thousanths too much. IF the chamber is on the large size and the die is on the small side of spec.s that WILL size too much!

Sizing so the cases chamber with only slight resistance insures they will be tight enough to prevent primers from backing out and then getting re-seated under pressure and made flat in the process.

That is exactly what I was referring to. This exact thing happened to me when I first started reloading. After 3 firings I started to get a sticky bolt on reloads before firing which meant my cases were not getting FLS all the way down so I turned out my FLS die as advise and the sticky cases disappear only to have somewhat flattened primers start appearing. I finally took a case that was very stiff to load and set my FLS Die until the stiffness just barely disappeared and no more flattened primers or sticky bolt issues n unfired loads. Since then I wised up and got the Hornady head space gauge.

quote:

Originally posted by bartsche:

quote:

Originally posted by delloro:
[QUOTE]Originally posted by bartsche:
Flattened primers are always an indication of a high pressure....

THIS WAS NOT MY QUOTE[COLOR:RED]'s message!!! JUST THE OPPOSITE!!!!! GO BACK AND REREAD[/color]
If you are going to quote someone please make sure you know what your doing and capture the intent and meaning of the whole quote.

correct me if I am wrong:

you wrote that flat primers are always a sign of high pressure

you also wrote that flat primers are not always a sign of excessive pressure

the intent of your statement seems to be that if the primer is flat, the pressure was high, but not too high.

I could have responded as follows, but the result would not change appreciably:

quote:

originally posted by bartsche:
Flatten primers are always an indication of a high pressure but not necessarily an excessive pressure.

not exactly; a low-pressure load with excessive cartridge clearance can do it. the FP drives the case forward, the primer backs out a bit, the whole case is shoved back, and the primer is mildly riveted but still within the pocket, quite flat. of course, because I am referring to low pressure primer flattening, excessive pressure scenarios don't matter.

quote:

originally posted by bartsche:
As others have stated a primer alone does not tell the whole story.

that's true, but you did state that flat primers always mean high pressure.

quote:

Originally posted by delloro:
that's true, but you did state that flat primers always mean high pressure.

Perhaps a definition of what is the border line between what is considered a high pressure and what is considered a low pressure would have helped.For example I do not consider 40,000 psi as a really low pressure. Mox nix. roger

quote:

Originally posted by Ckemp:
...I don't see a PM flag anywhere. I'll try to change my personal settings to allow it, although I don't remember setting it so that I wouldn't get PM's.

Hey Ckemp, In order to get to your "Personal Settings" you need to click on the "Go" button at the top of the page. If you can't get it figured out, let me know, and I'll copy my post here.

Just trying to avoid a brouhaha since I am so amiable.

quote:

Just trying to avoid a brouhaha since I am so amiable.

I enjoyed that one!

quote:

For example I do not consider 40,000 psi as a really low pressure.

Agreed. To me 50,000 CUP is high pressure. What is 60,000? (Other than scary). A definition of low, medium, high and scary high is needed.

quote:

Originally posted by Hot Core:

quote:

Originally posted by Ckemp:
...I don't see a PM flag anywhere. I'll try to change my personal settings to allow it, although I don't remember setting it so that I wouldn't get PM's.

Hey Ckemp, In order to get to your "Personal Settings" you need to click on the "Go" button at the top of the page. If you can't get it figured out, let me know, and I'll copy my post here.

Just trying to avoid a brouhaha since I am so amiable.

Thanks Hot Core. I was able to see the message after clicking on OK then personal settings then private message. I'm gonna read it now. I wonder why I didn't get a message saying that I had a PM? Thanks again.