Ran into some problems load testing today. Case damage I have never seen before

Are you positive that it was Varget? You can't fit enough in the case with that bullet to get that kind of pressure. Pinched neck? If you are trimmed to Max OAL, then check neck clearance. One way to get an idea of that is to measure the outside diameter of fired brass.

Too bad that your chrony is unreliable - you need to correct that. The best estimate is MV and 3300 fps is well......
 
175 GR. SIE HPBT
Manufacturer Hodgdon
Powder Varget
Bullet Diameter .308"
C.O.L. 2.800"
Starting Load
Grains 42.0
Velocity (ft/s) 2,583
Pressure 42,600 CUP
Maximum Load
Grains 45.0C
Velocity (ft/s) 2,690
Pressure 48,600 CUP


straight from here ; http://www.hodgdonreloading.com/data/rifle




your doing something seriously wrong , did you mix up your powder with something else ?


I have never seen the case head push out to look like a belt on a magnum case before

Well I am well below that level. I used other people's pet load data but all of it was below the hottest load I had worked up to which was 44.5.

I have loaded about 150 175 SMKs and none ever showed any signs of overpressure. No hard bolt openings, no catered primers.

The brass I purchased from another shooter. It was all Federal but some of the headstamps looked different. I thought maybe some were Gold Medal Match and the rest were blue box or American Eagle or something.

On top of that there was no excessive recoil or noise and I the round was clocked at 2599 FPS which was right where I thought it would be.

I'm new at this. I'm not saying I didn't do anything wrong but I only have one type of powder. I use a triple beam. I load in batches of five to ten rounds. All the other rounds worked fine and grouped sub MOA even.

I have no other rounds loaded up. I will take the rifle and the casing to a gunsmith and see what they say.

Could it have been a really worn out piece of brass? And for neck pressure I will measure them but I loaded them a half hour earlier and none felt any different than any others when seating.

Oh and one other thing my rounds are 2.865 OAL so they sot 0.015 off the lands. I had suspected brass but I really don't know.
 
Have you checked the bore to make sure there aren't any obstructions? For that kind of pressure something is seriously wrong and unless you used the wrong powder by mistake I don't think it is your Varget load causing it.
 
I am not an expert at reloading and may never be but I would not jump to your brass conclusion so quickly as your primer is telling you a story also and it seems to be indicating "high pressure".
 
Definitely pressure. Do not shoot any other loads. Only reload when you can stay 100% focused.

Based on what you say, I would say one of the following:

1) wrong bullet
2) too much powder
3) wrong case
4) wrong powder
5) residual powder in case?
6) you may be over max load for that rifle. Drop down 4% powder charge and you should be close to another accuracy node

I would just go down 4% and start over - you should be ok! Oh yes - with a rifle like that, I would use good brass. Toss what you are using then go buy some Lapua and have at it!
 
STOP! Have a very careful look at what you are doing cause something is way wrong, that is massive over pressure!

I've have the same result when I mixed up some 174gr SMK with my 175gr SMK bullets, 174gr are .311 not .308 and it makes a big difference with warm varget loads.

I would look at the bullets as well. Nothing else I've read about the OP and his reloading practices could over-pressure the round like that.

Sealed boxes of 100 or repackaged/bulk bullets?
 
I would look at the bullets as well. Nothing else I've read about the OP and his reloading practices could over-pressure the round like that.

Sealed boxes of 100 or repackaged/bulk bullets?


I agree......some of the advise and alarm is by people who obviously haven't read the whole story.

-Powder - if you only have one kind of powder, obviously the problem isn't there. Your weighing sounds quite meticulous, but of course there is always the possibility something went wrong and the charge was hot.
-Brass or primer - I doubt the problem is here....a tight neck shouldn't cause that much over-pressure.....and if the case chambered normally, then it isn't grossly over length or anything.

I'm going to guess either an obstruction....in which case you should find a bulge in the barrel.....or....for whatever reason, a larger calibre bullet (although I think you'd have noticed seating it) or heavier bullet.....again the question as above....were they bullets packaged from the factory?.....even if so, it is not impossible to have some kind of stray in there....maybe take all the bullets you have left and inspect and weigh them. Although it might have been a one-in-a-million thing...

I doubt that, unless your bolt-face is fire-cut, there is damage to the rifle, but of course, it should be checked.

Good luck.
 
I would look at the bullets as well. Nothing else I've read about the OP and his reloading practices could over-pressure the round like that.

Sealed boxes of 100 or repackaged/bulk bullets?

I once got a box of Nosler Accubond 165 gr 30 cal (box was scotch taped closed) that had in the same box 2 each 200 gr accubonds.... imagine that! Now when I buy bullets I ONLY get factory sealed or won't buy them.
I noticed when I went to seat them that they kept popping back out and didn't look right - popped out from powder compression - threw them on the scale and viola! 200 grains...
 
These bullets came in a 500 rounds sealed bulk box from the manufacturer.

Averge outside neck diameter after sizing was 0.336. After firing average was .343 and this one was .343. Average length after firing was 2.002. This one was 2.011.

This round contributed to a 0.9 MOA 150 meter seven round group. While that isn't amazing it isn't bad.

The other 20 rounds I fired afterwards looked exactly like the good one in the pictures. I was going to cut this one in half to see if the case wall was really thin or something.

I took a quick look at the bore but didn't see anything. It's still really accurate. It is boxed up to take to the gunsmith so I will look at it again in a few hours when I get there.
 
Please do keep us informed of any new info, I'm very curious as to the cause.

I'm also going to suggest the brass hardness be checked on the bad case, and be compared to the others, for all we know, maybe that case was pulled from a fire pit and tumbled before it was sold to you.
 
I've found .311 in a box of factory sealed .308 both HPBT, I thought I had screwed up and mixed up bullets as I have both normally, but then the chill of realization hit that I had started from a new un-opened box. It didn't even feel that hard seating but just enough for me to check.
 
STOP! Have a very careful look at what you are doing cause something is way wrong, that is massive over pressure!

I've have the same result when I mixed up some 174gr SMK with my 175gr SMK bullets, 174gr are .311 not .308 and it makes a big difference with warm varget loads.

The same result as in the same case damage?
 
Been reloading since 75 .I remember once or twice finding wrong cal.bullet in factory sealed boxes. From what I've read when they change making one caliber to another the same trays are used To collect sometimes being human they miss one.
 
The same result as in the same case damage?

May cases looked exactly the same and I had to remove the bolt to force the brass off of the bolt face as it was stuck like you describe. The 174gr .311 bullet is almost impossible to tell from a 175gr .308 just to look at it and it seats just fine, not not with any noticeable extra effort like you might think.
 
I'm very doubtful that a .311 bullet would cause that much overpressure, as long as it was the same weight. If you seated a 190 grainer instead of a 168, say, then it could happen.

Are you using a funnel to drop charges into the case?
If so, you may have experienced a "bridge" in the funnel, which would undercharge one case but quite easily overcharge the next when the bridge of powder is added to the original charge.

There is also the possibility of a case with much less internal volume, but that is grasping at a straw, basically.

In any instance, it takes a lot of pressure to do what you see to that case.

Regards, Dave.
 
On top of that there was no excessive recoil or noise and I the round was clocked at 2599 FPS which was right where I thought it would be.

I'm new at this. I'm not saying I didn't do anything wrong but I only have one type of powder. I use a triple beam. I load in batches of five to ten rounds. All the other rounds worked fine and grouped sub MOA even.

I have no other rounds loaded up. I will take the rifle and the casing to a gunsmith and see what they say.

Could it have been a really worn out piece of brass? And for neck pressure I will measure them but I loaded them a half hour earlier and none felt any different than any others when seating.

Oh and one other thing my rounds are 2.865 OAL so they sot 0.015 off the lands. I had suspected brass but I really don't know.


my thoughts are this .

as someone else mentioned , the case head may have either been annealed , or had gotten hot enough to be annealed sometime in its past .
what looks like a massive over pressure , could be just normal pressure with a soft case head .

myself I would also seriously look at the distance between the bolt face and the end of the barrel .... my "spidey senses " are tingling on this one ... it may be very possible that the space there is on the excessive side . maybe not enough on its own to cause issues , but when coupled with something else that may be minor ......




I wouldn't get freaked out about having to only use stuff from a sealed box straight from the factory ....factories make mistakes all the time , stuff gets counterfeited all the time .
million upon million of rounds are fired in Canada with used , recycled components from unsealed boxes of primers , bullets and powder , with no bad effects .

it comes down to thinking about what your doing and using sound judgement .


before I rebarreled my 270 I had some hot loads worked up on Remington brass . I was going to reduce the load by one grain on the next batch . I had 2 round left over and I didn't really want to tear them apart so I fired them off . the first one wasn't so bad , but the primer did fallout when the case was removed , the second one look just like your pics , but without the brass flowing into a "magnum belt " .
they where both federal cases .( they had a much smaller case volume than the Remington brass , thus much higher pressure ).

having cases that are all the same internal volume is sometimes very crucial .
the case heads don't necessarily need to be the same stamp , but the volume needs to be within the same variation that cases out of the same batch / same head stamp would have .




EDIT ........

this is why I think it is a soft case head ....... " no excessive recoil or noise and I the round was clocked at 2599 FPS which was right where I thought it would be."

if it was a overload situation , the recoil would be noticeable enough that you would take notice ..... and assuming your chronograph is working , your velocity would be higher that you would be expecting .
but if the case head was soft , this wouldn't happen
 
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Wow.

My thoughts;

Bullet puller.
Measure the load on a quality scale.
Look in the reloaders handbook and figure out what went wrong.
Don't make more than 5 of anything until you know they are good.
Count your blessings that you still have your trigger finger and no extra bolt shaped hole in your forehead.

C
 
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