Fired Case Issue - 460 WB

[jstanfor8]

Anyone ever encounter this situation with a reloaded round? This happened to two cases from a 460 WB trimmed and prepped, etc., like normal and seemed to have no defects prior to firing.

 

[PddPdd]

Does the thickness of the neck seem consistent or thinner in the elongated areas?

 

[cdherman]

I assume you full length resized? Do you have a gauge to measure your case base to shoulder? I am wondering if the gun is very generously headspaced and you are seeing a massive case stretch? The WBY of course shoulders off the belt, but it blows out the case to match the chamber nonetheless when fired.

 

[Varmint Hunter]

I've shot a lot of 460Wby factory ammo and my hand loads. I have never seen that happen to a piece of brass.

 

[jstanfor8]

Does the thickness of the neck seem consistent or thinner in the elongated areas?

Subject to human and/or instrument error, looks like case thickness appears a little thinner at .0130 vs .0135-0.140 outside of the elongated area. Also, note from above that it's no longer perfectly round.

 

[jstanfor8]

I assume you full length resized? Do you have a gauge to measure your case base to shoulder? I am wondering if the gun is very generously headspaced and you are seeing a massive case stretch? The WBY of course shoulders off the belt, but it blows out the case to match the chamber nonetheless when fired.

Correct full length resized, and I have an LE Wilson adjustable case gage, but I understand that the factory chamber of WBY rifles have a long freebore from .975" to .756" depending on the age of the rifle--not sure about mine, but it's a factory Mark V made in Japan.

 

[quigley257]

What bullet was fired? It looks as if the brass was crimped deeply into a cannelure and then dragged out as the bullet left the case.

 

[jstanfor8]

I've shot a lot of 460Wby factory ammo and my hand loads. I have never seen that happen to a piece of brass.

yeah, crazy

 

[PddPdd]

Couple of questions:

1. Have you inspected or cleaned the rifle chamber recently? Borescope images?
2. Did you fire any rounds at the same shooting session that did not elongate the brass?

 

[jstanfor8]

What bullet was fired? It looks as if the brass was crimped deeply into a cannelure and then dragged out as the bullet left the case.

500 grn CE Solid so it was crimped over the cannelure

 

[jstanfor8]

Couple of questions:

1. Have you inspected or cleaned the rifle chamber recently? Borescope images?
2. Did you fire any rounds at the same shooting session that did not elongate the brass?

Yes, perfectly cleaned rifle before this round at the range, but not borescope images. I fired a total of 27 rounds--5 with 500 grain CE Solids 2 of which resulted with this elongation and then 22 rounds thereafter with 500 grain Barnes FJM RN with no issues.

 

[Varmint Hunter]

27 rounds of 460Wby ammo in one session - You da man!!

 

[PddPdd]

What are the pre-fired diameters of the CE solid rounds and the Barnes rounds?

 

[cape cove]

If that is Weatherby ammo I would send them a picture of the elongated brass. See what they think of this. JMO