Need some help with a problem after annealing....

shootist22-250

shootist22-250

Regular
EE Expired
Rating - 100%
2   0   0
Location
In the middle of gopher country
I annealed (hopefully at the correct brass temperature) some Winchester 223 cases. During annealing the cases were set in a pan of cold water to a depth of approximately 3/4 of an inch. I am not sure that I reached a high enough temperature during the process. The method used was that when the case, in a darkened garage, glowed a dull red it was tipped into the cooling water.

Then they were reloaded using the same recipe that has been used prior to this.

When these reloads were fired, the pressures were wayyyy up. Up to the point where the firing pin strikes on the primers were protruding on some cases instead of being recessed.
The load is 20.9gn of IMR 4198 underneath a 55gn Winchester using a standard CCI small rifle primer.

Thoughts anyone?
I am thinking that maybe the necks got hardened instead of softened by insufficient heat during annealing. Can this happen with rifle brass?
 
Last edited:
No, you cannot harden brass by heating it. And, if you got it up to glowing you were plenty hot enough to soften the neck considerably.

Do you crimp? That is the only thing I can think of that would be changed by annealing. Though it would take a pretty monster crimp to raise the pressures significantly.
 
"...glowed a dull red..." That's too hot. Heat the neck and shoulder until the brass changes colour and tip 'em. Annealing won't do anything to the pressures.
"...using a standard CCI small rifle primer..." Out of the same box you used before annealing.
20.9 grains of IMR4198 is .5 grains over max, but that shouldn't cause terribly excessive pressures. If the primers aren't backing out or you're not having hard extractions, etc., I wouldn't worry too much about it.
 
HKMark23 said:
Were cases trimmed and still at or under maximum recommended length?

They should be less than 2.2598".
Click to expand...

Thanks for your input guys..........
1. No crimp involved here.

2. The minimum length of the 50 cases in question here is 1.065" and the max is 1.755"

Over all bullet length is not an issue with this barrel as the throat is somewhat washed out. Bullets are currently seated with 0.050" of bullet inside the case neck. Yes, you read correctly 0.050" of bullet inside the case neck. So yes, the bullet is long according to loading manuals but not long according to this barrel and chamber. The bullet is 0.010" off the lands (such as they are).
Oddly enough or maybe not, this Tikka will still do 4 shot groups touching (if I do my part) at 100 yards.

Off topic here.... it is going to be interesting when the throat erodes further as to what will happen to the accuracy. I will find out probably by the end of the current squeak season.
I hope it behaves like my Sako 22-250 with a Ron Smith barrel on it. The freebore to the lands after I seat a bullet is approximately 0.20" currently. The barrel still shoots 0.7" groups when I have a good day.

Thanks guys
 
sunray said:
"...glowed a dull red..." That's too hot. Heat the neck and shoulder until the brass changes colour and tip 'em. Annealing won't do anything to the pressures.
"...using a standard CCI small rifle primer..." Out of the same box you used before annealing.
20.9 grains of IMR4198 is .5 grains over max, but that shouldn't cause terribly excessive pressures. If the primers aren't backing out or you're not having hard extractions, etc., I wouldn't worry too much about it.
Click to expand...

Ummm ... something here is haywire!!!
I am sitting here looking at my Sierra Reloading manual and it says 21.9gn is max.
Hodgson's website says 21.0gn

Where does the max spec of 20.4gn come from?
Primers are from the same batch number. I got lucky a year ago and purchased a rail car load full. Just kidding on the rail car but I did buy a whole shwack.

Secondly, as I stated in my initial posting. Pressures were not an issue prior to annealing.

Thanks for your input.
 
Last edited:
shootist22-250 said:
Ummm ... something here is haywire!!!
I am sitting here looking at my Sierra Reloading manual and it says 21.9gn is max.
Hodgson's website says 21.0gn

Where does the max spec of 20.4gn come from?
Primers are from the same batch number. I got lucky a year ago and purchased a rail car load full. Just kidding on the rail car but I did buy a whole shwack.

Secondly, as I stated in my initial posting. Pressures were not an issue prior to annealing.

Thanks for your input.
Click to expand...
make sure that u are not useing small pistol primers. they are the same
size but the cup material is thinner. pull a bullet and weigh the powder.
make sure it's 4198. my lyman book gives 21.7 as max.
jb
 
Remington 7 1/2 have a much harder cup to stand pressure better, which is why they are used in the 17 rem and 17 rem fireball. Calhoon has also measured thickness of small rifle primers, and they do vary. Go to www.jamescalhoon.com and check under the informative articles page, primers and pressure article. CCI BR4, and federal 205M are thicker as well.
 
Annealing increases the 'springback' of the brass. Depending on what specific method of resizing you're using this could result in an increase in neck tension on the bullet and should result in more consistant neck tension, which is one of the goals of annealing in the first place.

Is this the first time you've annealed with this load?

Is it possible that the increase in pressure is simply due to an increase in neck tension?

Were the insides of the necks cleaned after annealing? I've had some freshly annealed cases stick to the mandrel of a Lee Collet Die once. I've yet to figure out why, but it may have had something to do with the condition of the inside case neck surface as they weren't cleaned or touched after annealing was done. Maybe your bullets are sticking in the case necks in a similar fashion.
 
TwoTone said:
Annealing increases the 'springback' of the brass. Depending on what specific method of resizing you're using this could result in an increase in neck tension on the bullet and should result in more consistant neck tension, which is one of the goals of annealing in the first place.


Some good thoughts here, thanks...

The cases were neck sized after annealing.

Is this the first time you've annealed with this load?
Yes

Is it possible that the increase in pressure is simply due to an increase in neck tension?
How much neck tension can you gain when you are holding only 0.050" of the bullet with the neck? It'a a question because I sure don't know. Probably minimal I'm thinking.


Were the insides of the necks cleaned after annealing? I've had some freshly annealed cases stick to the mandrel of a Lee Collet Die once. I've yet to figure out why, but it may have had something to do with the condition of the inside case neck surface as they weren't cleaned or touched after annealing was done. Maybe your bullets are sticking in the case necks in a similar fashion
On this I'm thinking of the above scenerio of bullet depth. Would it matter? However, I shall scrupulously clean the inside on my test session..
Click to expand...

For what it's worth, I'm working up new loads with annealed cases. Have to see how that goes and if there are any changes from my old load data.
 
.050" seating depth.

Yeah, I didn't think about that when I mentioned neck tension. I forgot you mentioned it. I doubt you could get enough extra tension to notice anything different with that shallow seating depth.

If the bullets were somehow sticking in the case necks however, I would think that might be noticable.

Keep us posted.
 
what was the outside temperature at when you did your work up load compared to now? I have summer and winter loads for varget in some calibers that require the extra 1 to 1.5 grain of powder to get the same velosity in the dead of winter as I get in the summer. Also elevation can have something to do with it as well, if you are shooting closer to sea level now your pressures will increase with the same load.


food for thought
 
yodave said:
what was the outside temperature at when you did your work up load compared to now? I have summer and winter loads for varget in some calibers that require the extra 1 to 1.5 grain of powder to get the same velosity in the dead of winter as I get in the summer. Also elevation can have something to do with it as well, if you are shooting closer to sea level now your pressures will increase with the same load.


food for thought
Click to expand...

Elevation has not changed. I have been shooting the same adjacent pastures for 6 years now. It's called selective culling of the herd:D

Loads are all at pretty much the same temperatures. Ranging from 15C to 30C.

I think maybe I'm onto something in this situation I am having. There is a real difference in the neck tension when the sizing ball comes through the neck of the case. This is after the neck is compressed on the upstroke of the press ram. Which tells me that the necks are definitely softer.

So far nothing definitive has shown up as to why the pressures have gone up so high. It is quite strange how the pressure has changed. Performed another annealing on the brass. Tried the loads again at 20.9gn, same situation resulted. What I did learn is that the barrel also likes 19.6gn just as well. At 19.6gn there are no indications of excessive pressure and the annealed cases are just as accurate as the 20.9gn.

Time to pull all the 20.9 reloads and go to 19.6gn. I'm off for a week long gopher bust tomorrow. I may have time to resume this quest after getting back.

Thanks for all the ideas guys.
 
Sorry TwoTone, annealing does not increase the springback of the brass. Annealing reduces the tensile strength; it is softer. It will not increase the bullet pull, and may even reduce it. Without annealing the sizing die reduces the neck diameter and the expander plug pulls through it, and the brass will spring back slightly to a smaller diameter. After annealing, the expander plug will pull through and the brass will not spring back to a smaller diameter, or if so, it will be less. Annealing might result in more consistent bullet pull, as all cases will be set to the same softness, something that might not happen to mixed lot of cases with varied amount of firing.
 
An update..........
The problem has almost gone away.
Annealing the cases has eliminated the "soot" on almost all of the cases. Out of a batch of 50 cases only a couple still display blackening. However, not to the extent of previously encountered. Prior to annealing the soot covered 80% of the case. Now when it does occur only the neck is affected.

Thanks for all your help guys.
Once again CGN comes to rescue.
 
I was thinking about this during my run tonight. You mentioned that the pressure had gone way up, when you probably meant that the apparent signs of pressure had gone way up, due to the primer being a bit cratered and coming out a bit.
I would suggest that your pressure had not gone up, but that your well annealed cases were sticking to the chamber (due to the lack of springback and lack of tensile strength)
which meant that the cartridge was not slammed back to reseat the primer. The headspace allowance meant that the primer could back out a bit.
 
Al-Sway...
that may well be except the primers are not backing out.

After all the discussion I went back to an old recipe that was used for a long time while building loads for this rifle. Backed off 1gn on the powder and all is well. The mystery of increased pressure will have to wait for another day.

Thanks
 
This is where a Chrony comes in handy. If velocity is about the same, then it is the appearance of pressure that has changed, not the pressure. higher prssure with the same powder would mean higher velocity.
 
You must log in or register to reply here.
Back
Top Bottom