What caused my case to do this? (Help)

[snider6464]

I have a 30-378 Weatherby that i handload for, everything has been fine except these two cases. All the rest of the rounds that i have fired have been fine all 180 of them. These seem to have folded in just behind the shoulder after i fired them, again this was after i ejected the round i discovered the defect, was fine when i loaded the round. these were around 20 rounds apart as well. any thoughts? Thanks

 

[Broz]

It looks like a low powder charge. If you are at the low end of the scale bump up the charge a bit. Or select a different powder.

Jeff

 

[snider6464]

Yeah might be it. but the load data that i got from berger was
210 Grain H1000 94.5 99.5 90.8% fill ratio
and im loading at 97.0 so its not to low by their standards.

 

[trueblue]

What are your velocities?
Do they seem out of line?

 

[snider6464]

I haven't chronographd them in a while but they were around 2910 seemed close to bergers estimation and others guestiments... maybe i will again.

 

[snider6464]

here is what the Snipers hide guys are thinking

What caused my case to do this? (Help) - Sniper's Hide Forums

Thanks

 

[Nimrodmar10]

The same thing has happened on smy 7 RUM. It's caused by the freebore that Weatherby and by Remington in it's Ultra Mag shells. They have lots of freebore like the Weatherby. It has something to do with the seating depth of the bullet and the freebore allowing gas to bypass past the neck which does not seal With mine it was with a Berger 180 gr. VLD. I'm guessing you were using a VLD also.

 

[4xforfun]

How accurate is your scale? Next time you load, throw one or two of those 210 bergers on the scale. They are as good a divice as any to check your scale's accuracy.

Just a thought.
Good luck

 

[Cornfield Flats]

It's likely from slight gas leakage due to a low chamber pressure. If the case is headspacing on the belt rather than the case shoulder there can be some space betwen the case shoulder and chamber. A low pressure load will not cause the case to expand enough and completely seal the chamber.

Hope you find your solution.

 

[travelr47]

It appears to be a classic situation of excessive case
lube (RCBS specifically), when resizing one's brass.
One of the many reasons I quit using this type of
sizing lube decades ago! For the last ten years or
so, I've been using sizing wax, which works perfectly
and cleans up easily.

I've never seen this as an aftermath of being fired:
being chambered looking perfect and coming out of
the chamber looking like this.

But since you didn't specify when this happened, and,
just in case it showed up after being fired, I'd suggest
it would be a result of anything caught in the chamber
between the loaded cartridge and the barrel's chamber.
Not having anywhere to go, it stayed put and dented the
cartridge case.

 

[devildogandboy]

new guy here and first post.
i believe it's too much freebore also. just like everyone one else, gases are escaping around the neck-shoulder area. i would check case length after sizing and check COL. maybe seat the bullets out a little further if you can safely!

those dents are not due to over lubeing. they would have blown out after shooting.

good luck.

 

[rscott5028]

While it may be more common with lots of freebore, that's not the cause of the condition. Like Broz stated, it's caused by not sealing due to an insufficient powder charge.

The other condition that would cause this is if there are any flakes or grains of unburned powder in the chamber when the cartridge was fired. ...like from having a bullet pull loose and spill powder in your chamber and magazine. (Just don't ask how I know about that. )

-- richard

 

[devildogandboy]

While it may be more common with lots of freebore, that's not the cause of the condition. Like Broz stated, it's caused by not sealing due to an insufficient powder charge.

The other condition that would cause this is if there are any flakes or grains of unburned powder in the chamber when the cartridge was fired. ...like from having a bullet pull loose and spill powder in your chamber and magazine. (Just don't ask how I know about that. )

-- richard

i will respect your wishes and not ask how you know (we all have our little secrets). i see a load for it being 99-104 grns of H1000 and see that the problem may be too light a load.
i have learned something today that i have never encountered. thank you.

 

[meatyrem]

The same thing has happened on smy 7 RUM. It's caused by the freebore that Weatherby and by Remington in it's Ultra Mag shells. They have lots of freebore like the Weatherby. It has something to do with the seating depth of the bullet and the freebore allowing gas to bypass past the neck which does not seal With mine it was with a Berger 180 gr. VLD. I'm guessing you were using a VLD also.

I would think and this mho, if there was gas leakage wouldn't the indents be darkend a little like it is around the case mouth? And why would the shoulder be unharmed and the dents appear after (behind) the shoulder?