Reloading Question

[Robin]

The above pictures are hand loads using a powder new to me, Benchmark. I am at the maximum load listed in my book with this load and would like some opinion's as to the primer flattening out and is this considered excessive. Shown are three fired and one unfired to give you an idea of before and after. Using 90gr. Gold Dot, they are canalured and I give them a slight crimp with a separate die. I admit I am trying to get the most I can out of it for a hunting load but at the same time I don't want to beat up the gun or more importantly I don't want to create an unsafe condition.
In the shooting of them, I didn't perceive any undue recoil or anything else that would tell me I am in dangerous territory. The only thing I can find is the flattened primers.
I appreciate opinions from those with more experience than I, for now, everything is on hold.
Robin

 

[kev74]

It seems like some primers are softer than others, and tend to flatten easier. If you're not exceeding the "never exceed" load, and if there are no other indications of overpressure, I think you're ok. I can't make out an impression of the breech face, and don't see any metal flow into the firing pin hole, so that's good too.

If you can get your hands on a chronograph, that will set your mind at ease a bit more than internet reassurance.

 

[Robin]

I just got a chronograph but wanted some opinions on this before I reload a whole batch. Thanks Kev!
Robin

 

[togmaster]

The way I see it, the fact that the primers are flattening like that would indicate you are approaching the upper limit of that load.

 

[Mosinitis]

I don't shoot 6.8, but for 223 this is acceptable. When firing pin indentation starts blanking out (getting lighter), that's a sign to back off.

 

[ManrisFrack]

So I use the old 110gr AB SSA Tactical load for hunting and all of my primers look like that.

My opinion: In the absence of another pressure sign (cratering or swipes) I would use that load - especially if it was mainly used when the ambient temp is 30+ degrees lower than now. I wouldn't go any higher than that and I wouldn't shoot them on a 90degree day.

What primer are you using? I know CCI 41s are a little bit harder than most and will show pressure later.

 

[Robin]

Primers are CCI 400. What is meant by 'swipes'?
Robin

 

[Mosinitis]

Avoid Winchester primers, they pierce easily. They used to be good years ago, but now the cup is too soft. Your fired brass looks fine.

 

[minderasr]

Avoid Winchester primers, they pierce easily. They used to be good years ago, but now the cup is too soft.

Interesting. I've been loading with Win primers (small & large pistol) for a while now and have never had an issue. Much to ponder.

 

[Mosinitis]

Interesting. I've been loading with Win primers (small & large pistol) for a while now and have never had an issue. Much to ponder.

There is a known problem with Win. small rifle primers (he is using small rifle primers). It may or may not be a problem for other types of primers of this brand.
That being said, doesn't mean they are unusable. Only that the chances of them piercing are greater.

 

[ManrisFrack]

Primers are CCI 400. What is meant by 'swipes'?
Robin

Swipes are the marks on the case head caused by the ejector hole and the cutout for the extractor. If the pressure is too high, it will extrude the case material back into these unsupported sections. When the bolt rotates it will smear the brass that has slightly extruded into the bolt recesses. The right case in your pics seems to show the faintest indication of an ejector hole mark. It isn't anywhere near severe enough to worry about.

You can see swipes on the cases in the pic below. Note the top of the top case. It has a triangular shiny spot where the brass flowed into the extractor cut and was smeared as the bolt rotated. You can also see cratering around the primer mark and that primer mark is flat at the bottom and shallower than it should be (the tip of your firing pin should be round and it should leave a rounded impression). These were where I stopped during my 30 Herrett workups and even my hunting loads are a few tenths of a grain lighter than this for a bit of a margin.

Swipes can also be caused by fast timing (too much gas), burrs left on the bolt face from manufacturing and a few other things. Because of this, they aren't the end all, be all of pressure signs but if you have them with another sign, like cratering or flat primers, you better stop pulling the trigger and figure out what's going on.



ETA: CCI 400 cups are 0.005" thinner than the 41 cups from what I've read. The 400s will show pressure signs at a lower pressure because of this.

 

[Mosinitis]

You can see firing pin indentation blanking out in the above picture. I always go by that.

 

[Robin]

Thank you Manris, I'm heading out to the range this morning with my chrono and I'll keep an eye out for that. I hope all is well, this should be a very good hunting load.
Robin

 

[zzrguy]

Check your crimp and bullet tensions you may be to hot as the case is show a stamp from the ejector and extractor on it.

 

[ManrisFrack]

Check your crimp and bullet tensions you may be to hot as the case is show a stamp from the ejector and extractor on it.

My cases or Robin's? Mine are clearly max or slightly over. They were the top two loads on ladder workups for two different bullets. On Robin's I see just a hint of one ejector mark.

 

[Mosinitis]

I don't crimp. It's an unnecessary step that can introduce inconsistency. Most sizing dies designed to give around 0.002" neck tension. That plenty tight to hold the bullet in place. Nobody that I know of in my sport crimps their ammo.

 

[Robin]

Interesting Mosin, that seems counter-intuitive to me. The reason I purchased a crimping die was because I wanted a consistent grip. I have had 8mm bullets slip upon recoil and I never max out my loads per the books I have, bought a crimping die fo it and, no more. Hmmmm, have to think about this and do a little more digging.
Robin

 

[zzrguy]

Sorry meant to say check your not crimping.
I had a seating die set a little to deep and was applying a slight crimp which flatten all the primers.

 

[Mosinitis]

Interesting Mosin, that seems counter-intuitive to me. The reason I purchased a crimping die was because I wanted a consistent grip. I have had 8mm bullets slip upon recoil and I never max out my loads per the books I have, bought a crimping die fo it and, no more. Hmmmm, have to think about this and do a little more digging.
Robin

Crimping doesn't make the grip more consistent, because small differences in case length become a factor. Neck tension is what has to hold the bullet in place.
To measure neck tension subtract the outside diameter of the neck before the bullet is seated from the outside diameter after the bullet is seated. If it's around 0.002", this should hold the bullet well. To see for yourself, you can use kinetic bullet puller to see how much of an impact is require to move the bullet. It's quite a bit.
BTW, no one I know of in my or similar shooting sports crimps. This is not something I don't do, it's a well accepted practice.

 

[zzrguy]

I don't crimp rifle round unless they are straight wall, but handgun round get crimped.

 

[SteyrAug]

Primers are worthless as a pressure indicator. Get a Chronograph !!!!

 

[Mosinitis]

I am not even going to touch this.

 

[Robin]

This too shall pass. I mean, who cares if your blowing primers as long as you know how fast the bullet went.
Robin

 

[tony]

Robin,
I believe primer condition is the first indicator of heading into higher pressure territory. Not necessarily excessive pressure but upper end pressures. The round corners of the primer should IMO stay somewhat round. The more they fill the pocket the greater pressure. The swiping mentioned earlier is a very good indicator as well. If you have swiping and further flattened primer you are there and should lower your charge enough to eliminate the swiping IMO. I'm sure you are aware the loading manual is nothing but a reference compiled with the firearm they did the testing with. What gives acceptable results in one may not work so well in another.
The blanking mentioned is something I have never noticed/seen. I have seen swipes and moderately flattened primers. Flat bottom primer dent looks different. I would think the firing pin should be staying there long enough to prevent that but I'm not really in the know with semi-autos... Crimping hurts accuracy and is necessary only if you need it to prevent bullets from moving back into the case from battering in the magazine. I crimp revolver bullets to prevent movement the other way.
As a side note, rarely do max loads give the best accuracy.

 

[SteyrAug]

BS, different brands and different compounds show far different results. A super hard primer like a Tula magnum will show no pressure while a softy like a std Remington will scare you to death.

This subject has been covered in depth in every decent loading manual for years as well as all over the net.

An up to date loading book and a chronograph (unless you can afford pressure transducers) is the best way to judge what's happening.

By the time primers are falling out, you can't lift the bolt and the case heads are deformed, you are already asking for it.

Your load's velocity, given the SAME components, should never exceed the maximum velocity shown in CURRENT loading data. Follow that rule and you're safe !

If you want a 300 Win Mag, buy one, don't try and make your 30-06 be one.

 

[Robin]

What?!?!?!?!? Did you unblock me? Please renew my blockage.
Robin

 

[Mosinitis]

The blanking mentioned is something I have never noticed/seen. I have seen swipes and moderately flattened primers. Flat bottom primer dent looks different. I would think the firing pin should be staying there long enough to prevent that but I'm not really in the know with semi-autos...

Gas pressure will push against the firing pin, hammer and hammer spring. As the pressure increases the dent will rapture, thus blown primers. Some flattening of the primers in AR's are relatively common and acceptable. Excessive flattening will also show some blanking. For most shooters there is no reason to approach these pressures.
If one shoots AR competitively from 200yd to 600yd, wind bucking gives a bigger advantage than fraction of MOA accuracy loss/gain. As much as it is not recommended to push the envelope, people will do it to stay competitive. It's don't do what I do kind of thing.

 

[Mosinitis]

Here is an example of blankening (both shot in the same rifle). The case on the right is showing excessive pressure. It shouldn't get to this point unless you really really really know what you are doing and in control of all other factors.
When reloaded military brass is used as often the case with .223, primer flattening is somewhat obscured by the remnants of primer crimp. Comparing firing pin dents gives a better picture. The dent on the right is smaller in diameter and not as deep. Other marks on the reloaded case head don't really tell you much, because they could be there from the prior firings. I don't even look at them.

 

[Mosinitis]

BTW, when the primer is pierced you probably won't even notice it until you pick up the case. There will be some damage to the firing pin tip, the rifle will still function but rough tip will be more likely to pierce another primer. Firing pin will need to be replaced. Alternatively the tip can be re-polished, if one is too cheap to buy a new pin.
During rifle cleaning I always run my finger across the tip of the firing pin to check for damage. It only happened once way back. No big deal.