Cause of this brass deformation?

[Dentite]

Hey guys,

Any ideas as to what may have caused this? This is brass that has been reloaded only once or twice. Mild plinking load. This is the first and only time I have noticed this but it could have been present all along I just never noticed it (easy to miss something this subtle when handling a few hundred cases).

I'm referring to the bulge in the brass around the primer in the one case in the middle of the group. I didn't feel any noticeable hard effort priming but S&B do have tighter primer pockets from my experience.

Any ideas of the cause of this?

Thanks.

 

[Dentite]

One more

 

[Bovice]

I have no idea. But I wouldn't use it. Deprime it gently and put the primer into a non-deformed case.

 

[frankenstein406]

be interesting to cut it in half and compare it to another case.

 

[119er]

Looks like your decapping assembly may be adjusted too low and squeezing the case web and deforming it or making it conform to the hole in your shell holder.

That's my guess

 

[gamestalker]

^^ That is kind of what it looks like to me as well? I've never personally seen anything like that before.

Could also a firing pin insert in a S&W that is excessively too high. I say that because most of those heads looks like they are exhibiting some remarkable and similar signs around the pocket too, just not as defined. So maybe that particular one experienced a bit more pressure, or the insert for what ever reason got pushed up higher. I would definitely keep an eye on that particular revolver just in case.

GS

 

[243winxb]

Firing pin Bushing?

Changed my mind. Soft brass & high pressure needed to seat the primer is compressing the brass. Primers look seated deeper than normal? Wild guess. Or a fining pin bushing problem?

 

[ironworkerwill]

Baloon head brass with too much force behind the priming mechanism?

 

[Dentite]

Thanks guys. This was the only case out of 250 or so that I was working on that exhibited this. I think you are right...priming deformation. I'm thinking maybe a flaw in the brass because it's the only one like that and I don't remember really squeezing one but I might have. I'll try to lay off the weight room and see what happens.

 

[ArchAngelCD]

That brass looks like it might have been deformed while removing the primer. It looks like there is a crimp in those primer pockets and if you have to use excessive pressure to remove the primers it might have caused that type of bulge in the bottom of the case. (just a wild guess though)

 

[Walkalong]

No way seating a primer did that.

it could have been present all along I just never noticed it

That is more likely.

 

[ArchAngelCD]

In any case it's very strange. I have never seen anything like it before either.

 

[Dentite]

There is no crimp on the primer pockets that I can see. S&B brass does have a more square opening at the entry point of the primer pocket as opposed to a chamfered edge seen in other types of brass (at least in my experience using .38 and .223 S&B brass).

I looked at it again under magnification tonight and I see that the primer pocket itself is a little distorted...slightly oblong in shape. I think I'll chalk this one up to some kind of manufacturing error, etc. I have to guess it's been there all along but who knows.

I do know that it has has survived the initial firing and one or two reloads, but I'm going to put it in the scrap bucket.

Thanks again guys.

 

[ljnowell]

Baloon head brass with too much force behind the priming mechanism?

Unless those are some super old cases, its not balloon head brass. Thats long discontinued.

 

[silicosys4]

wont happen during depriming, in my experience. I have adjusted my depriming assy a little too far down before and just ended up bending the assembly, not deforming the brass. I second that the brass was like that and went unnoticed.

 

[NCsmitty]

It appears that the P. pocket is messed up to begin with, and I would chalk it up to a single anomaly at this point. Toss the brass in question, save the primer if u want, and get on with the loading & shooting.


NCsmitty