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Discussion Starter #1
Before cutting to the chase just let me say that one of the facets of handloading is that it allows one to experiment.
I load for my 308 win chambered ruger #1 and neck size only. In a recent thread on here various theories were propounded regarding overloading.
I use either CFE 223 or N-150 powder and tbh prefer the cfe 223 even though my buddy gives me FOC the N-150 from a large tub he has.
So I looked at the max loads I was using with CFE223 and started loading 147 fmj hollow point boat tails, 3 at a time upping the load by 0.2 grains and then test firing them.
I use a magnetospeed chrono. At 1.2 grains over hodgdon's maximum load the cases started showing a mark where the ejector sits. At this load accuracy wasn't bad and velocity was just over 3100 fps with a deviation of around 25 fps ie max velocity was 3140 and min velocity was 3115 with the mean about 3125.
I'm now done with experimenting and a couple of things come to light
(i) the case is full right up to the neck at this load level.
(ii) the muzzle blast is huge.
(iii) no extraction or ejection problems, the cases neck size ok and the case hasn't stretched.
All I have is a small mark on three of the fired cases at that load level and on one of the cases from the load 0.2 grains lower.
I know it's only 4 cases but should I sling them or polish the mark off.
I've attached a pic and tried to put the cases so the mark is furthest from the ammo box but I managed to get the pic upside down. The marks were't there before this procedure and, tbh, I used a magnifying glass to check the cases out, bit OCD really. Primers look OK though.
Any thoughts?
 

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The extractor/ejector on a #1 doesn't touch the case when the case is in battery. I must not be seeing the mark you refer to.
The first sign of excess pressure in any #1 is in extraction.
The only signs I see of pressure is in the leaking primer. I would look at that case very carefully (microscope) and if a gas cut channel is seen in the primer pocket, hammer the neck shut and scrap the case.
 

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I can't see anything wrong in the picture, but I always suggest that you play it safe when reloading. In this hobby, there are a lot of risks, and brass is cheap. If you are questioning it, scrap it. There are a lot of factors that don't necessarily translate well into a picture or comment on a forum.

All that said, if it were me, I would probably do a "paper clip" test for case head stretching/separation and check for loose primer pockets. If those checked out ok, AND there are no other signs, I would probably load them again.
 

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Brass is relatively cheap, especially 9mm brass so if there is any question about it, just toss it and move on. Not worth the time to analyze it.
 

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The Hog Whisperer (Administrator)
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If one leaked a primer, chances are that the rest will very soon. 4 pieces of brass is a lot cheaper to replace, than to have work done on the boltface. Easy decision. Smack 'em with a hammer and in the bin.
 

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When in doubt

As others have suggested, destroy the suspect cases and move on. Especially if the brass had been loaded with maximum loads. Brass is cheap and the juice is not worth the squeeze. All the best...
Gil
 

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As Jack said and in this case it absolutely would apply because of the minimal taper on the body of the 308 the load would show pressure first by having a sticky bolt lift.
That being said one would think that the primers would be at least flattened a little, these show no signs of pressure.
The leaky primer in this particular case is indicative of some history with the case prior to this loading, it's not been treated nicely at some point.
My guess is that when that primer was seated this time it fell in with little or no pressure. The reason I believe that is I've had cases that I wanted to use until they were no longer usable because they either separated at the web, necks cracked or primers leaked due to the pocket being way oversized. Spend 20-30 minutes making a case for a hard to form wildcat, turn the neck a couple of times along the way with neck annealing thrown in with a less than 100% success rate and you'll find yourself gluing primers in with nail polish.
For a 308 maybe one of the most common cases there is any sign somethings wrong and they should go in the brass scrap bucket especially the common mfg cases your using.
If they were Lapua or one of the more expensive brands you might think about it.
 

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The Shadow (Super Mod)
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1) So I looked at the max loads I was using with CFE223 and started loading 147 fmj hollow point boat tails,
2) At 1.2 grains over hodgdon's maximum load the cases started showing a mark where the ejector sits. At this load accuracy wasn't bad and velocity was just over 3100 fps.....with the mean about 3125.

3) (iii) no extraction or ejection problems, the cases neck size ok and the case hasn't stretched.
All I have is a small mark on three of the fired cases at that load level and on one of the cases from the load 0.2 grains lower.
4) I know it's only 4 cases but should I sling them or polish the mark off.
I've attached a pic and tried to put the cases so the mark is furthest from the ammo box but I managed to get the pic upside down. The marks were't there before this procedure and, tbh, I used a magnifying glass to check the cases out, bit OCD really. Primers look OK though.
Any thoughts?
1) This confuses me, was it a HPBT, or FMJ ball ammo?:confused:
2) Over max charge, and over max velocity. So you're definitely over max SAAMI pressure, that's important to understand. Do what you want, just don't misunderstand what is happening.
3) Using those classic "signs" of pressure, is certainly better than nothing; but they aren't a good indicator of what your pressures really are. From a Pressure thread I did, "Signs" in the 308 *tend* to begin to show-up once you are over 70,000 psi.
4) As others have said, smash them with a hammer and throw them in the recycling bucket. An important aside and another reason why you shouldn't trust "signs", those are federal cases. Federal is rather notorious for having some soft case heads.
I've blown primers and stretched case heads in the extractor groove significantly with them, with PT verified 50,000 psi loads.:mad:


Cheers
 
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So, these cases were fired in a Ruger #1.
Is the case with the dark base colored with a felt pen?
If the cases extracted normally then you are not experiencing over-pressure signs.
The block, extractor and ejector does not hit the face of the head at all so it can't leave a mark.
The block, extractor and ejector does slide along a portion of the case when it is chambered and it is not abnormal for that to leave a scratch mark.
If you have serious doubts about the integrity of the brass, measure the diameter of the web just above the rim and compare that to your other brass. If the web has expanded or the primer pockets are loose then toss the brass. Check the insides of the case with a pick or bent paper clip to see if there is a groove forming just above the web. If you find the case has changed in these tests then toss the brass.

Honestly in single shot rifles, pistols and revolvers the first sign of over-pressure loads is cases sticking in the chamber or harder than normal extraction. If these happen then the brass should be tossed and the load reduced.
 

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Drone,

Without being sure of your barrel length or charge weight, I can't tell whether your velocity numbers mean anything much about the pressure.

If the barrel is 22", and if your chamber is tight and your charge weight is not over 53.5 grains of powder, two methods of estimating pressure based on Hodgdon's pressure and velocity measurements put your load between 66,300 psi and 66,800 psi. Those are not yet up in the proof range and are well within SAAMI and CIP allowances for pressures for individual rounds within an average of 10 rounds at 62,000 psi to reach. So while they are probably burning the throat up faster than necessary, it's hard to say they are actually seriously over pressure. A better estimate can be made knowing your charge weight and the as-fired case water overflow capacity of the brass (fired but not-yet-resized case with primer still in place is measured for length and then weighed and then filled with water level to the top (no meniscus and no air bubbles inside) and then weighed again and the difference in the two weights is reported together with the measured case length).

As mentioned earlier, some lots of Federal brass don't do all that well holding up to pressure. Lake City and Atlas Development Group and Starline produce the hardest heads, in roughly that order, so I would pick one of those, if I were in your shoes. The ADG has lower case capacity than the others, as it is designed with overall thicker walls for longer reloading life, so you might want to knock the load down a grain or so with it.
 

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Inspecting Cases

Cases that are straight, properly sized, trimmed, weighed and chamber easily will function interchangeably. Discard cases for wall thinning, loose primer pockets, obvious physical damage or if you know you have fired a too hot a round.

Case failures occur about 1/2" to 3/4" circumferentially above the case head due to wall thinning. Usually it occurs before there is visible ring indicating incipient case head failure so the case continues to be reloaded. Then the case is loaded hotter than normal. Most of the time its boom, boom, then BANG - case failure. A definitive check is done by dragging a paperclip or similar up the inside the lower case to detect the thinning condition. To rupture a good case requires a serious reloading error.

I've reloaded thousands of cases in the 308 family, including 243, 6mmRem, 257R and 30-06 and have only failed cases when they slipped thru inspection and were higher than usual pressure loads.
I've never had any adverse consequences from a ruptured case except to have to end shooting for the day, go home, pull bullets and re-check for wall thinning and powder charges.
 

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**So I looked at the max loads I was using.....and started loading fmj hollow point boattails.....upping the load by 0.2 grains at a time and test firing them.**

So you were conducting an exploratory pressure test, and think you may have observed some signs of excess pressure. Some have advised you to crush and scrap the brass. I would suggest that you spray some red paint on them, and save them for when you might be able to observe them (inside and out) with a microscope as JBelk suggested. You would need a dissecting microscope in the 10-50 power range...these scopes are usually binocular or stereoscopic, and are frequently used to examine electronic circuits for quality control. For example, a smooth sharp knife edge will appear very jagged and rough under 30-50 power.

The 100-300 power scopes used to observe bacteria would be useless for your purpose.

If the opportunity to use a scope arises, examine the primer pockets and primers as JBelk suggested, and section the cases and examine the inside case walls especially the lower case walls. You have gone to all the trouble of conducting this pressure test, and spent some time worrying about it. If you ever get to use a scope, you might see some really interesting things.

Personally, I would not have used Federal brass to conduct a pressure test. I have had premature cracks around the case head, and loose primer pockets with Federal brass.

I have an AR 10 and a HK 91 both in .308. The AR has smooth chamber walls, and the HK has striated or grooved chamber walls and the HK extraction is vigorous even with moderate loads. The HK will rip Federal cases in two, extracting the case head and leaving the front of the case in the chamber. Federal brass is soft (or weak). I recommend that you DO NOT use old Federal brass to conduct extreme pressure tests. Old brass can come apart unexpectedly...do not trust it.
 

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Discussion Starter #13
So, these cases were fired in a Ruger #1.
Is the case with the dark base colored with a felt pen?
If the cases extracted normally then you are not experiencing over-pressure signs.
The block, extractor and ejector does not hit the face of the head at all so it can't leave a mark.
The block, extractor and ejector does slide along a portion of the case when it is chambered and it is not abnormal for that to leave a scratch mark.
If you have serious doubts about the integrity of the brass, measure the diameter of the web just above the rim and compare that to your other brass. If the web has expanded or the primer pockets are loose then toss the brass. Check the insides of the case with a pick or bent paper clip to see if there is a groove forming just above the web. If you find the case has changed in these tests then toss the brass.

Honestly in single shot rifles, pistols and revolvers the first sign of over-pressure loads is cases sticking in the chamber or harder than normal extraction. If these happen then the brass should be tossed and the load reduced.
The staining was felt tip, when I worked up my original loads, I used red to indicate a charge of 0.5 grn less than the hodgdon max charge, those red end cases were then loaded with that increased charge and I used black felt tip over the red.
Uncle nick she's got a 26" barrel.
The bullets are 147 grn PPU FMJ HP boat tail, I've used them all now, can't get hold of any more due to lock down, but I have the same makers bullet without the hp, fmj BT at 150 grains a unit so I'll start over.
That painted case, btw has been loaded 14 times that I know of and the guy that gave them to me loaded them previously but I can't remember how many times he said so I won't speculate.
TBH I don't need that velocity so I'm going back to loading with N-150 as the 0.5 grain down on dne load fills the case to the bottom of the neck.
My experiment is completed, the load these cases were filled with filled the case to the bottom of the neck as I wanted to see if an accidental overload of cfe 223 would cause me problems, I figure that with these cases, in my rifle, they won't but don't see the sense in pushing it, as the load that gives me good accuracy also gives me around 2800 fps which is more than adequate for my needs. Muzzle blast is less, too.
All my federal cases are now into double figures of reloads in my hands so I reckon I've got my money's worth. I have a couple of 100 GGG match 7.62 nato cases so I'll fill those ones up for range use. I have a 100 or so PPU cases, that are equal to the best brass, that I load with soft point ammo for hunting.
 

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I see a small crater on the discolored one but the others look fine to me. What am I missing?
 
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