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Paslode
11-13-2011, 20:12
The (blurry) picture is of a 220 swift WW Super Casing with a vertical failure, at the beginning of the failure there appears to be a pin hole where it burned through. This was a hand load with 41gr Hodgdon H380, Nosler 55gr Bullet and a COL of 2.72

Hodgdon load data does not show any data for a 55gr. Nosler, the only 55gr. bullet they list is a Hornaday 55gr. SP with a min/max powder charge of 39-42.5 grain with a COL of 2.68.

This isn't my load, so assuming everything is as stated what would cause this type of failure?

Peregrino
11-13-2011, 21:05
Without the picture I can only speculate. My references show it to be a "moderate" load - nothing unusual/extreme. At that point it's usually traceable to a case problem. Brass work hardens which contributes to vertical cracks, usually in the neck. How many times was the case reloaded? Neck sized or full length? Trimmed? Has it ever been annealed? Does your buddy do neck uniforming? Lots of questions. My recomendation is to closely inspect the remaining brass from that lot and consider disposing of any that might be suspect. This is a case where it's best to err on the side of caution. Repeats can eventually cause damage to the rifle's chamber (NTM the possibility of serious embarrassment).

Paslode
11-13-2011, 21:25
Picture posted

Buffalobob
11-13-2011, 21:41
The 220 Swift is known to be subject to severe case stretching. The pinhole starts where a normal case head separation occurs. I have never seen a vertical split develop there but I would take a paper clip and check all of the cases for thinning above the web.

I would also take a few fired cases and roll them on flat surface and see if the chamber is OK.

Paslode
11-13-2011, 21:44
Picture posted

This was straight from the bag factory new casings. Beyond the load data and casing info I do not know.

Peregrino
11-13-2011, 22:15
Picture changes things a bit. I've had enough case head seperations over the years to be very conscious about headspace and overworked brass issues. BB is absolutely right about the start point (and I've never seen a vertical crack there either). Use the paperclip check he advises and inspect ALL of the brass fired that day. If you have a case micrometer, measure the fired brass. It'll show you if there's a problem with the headspace. If there is (and it's a bolt gun) a competent gunsmith can set the barrel back and re-chamber it for him. Good luck.

MVP
11-18-2011, 14:48
A couple of years back I bought some new WW brass, I had six or seven that were unusable and two did not even have flash holes in them. Don't use WW anymore, only Rem, Lapua and Starline now.

MVP

The Reaper
11-18-2011, 18:00
You are certain that the barrel is properly chambered and headspaced for a .220 Swift, correct?

TR

EchoSixMike
04-04-2012, 05:45
I'd vote for improperly formed case with resulting brass embrittlement. I too run a 220Swift and have had several WW cases with extended folds running lengthwise on the case. As stated, brass work hardens, so this fold fails(cracks) upon firing instead of expanding to conform to the chamber.

I believe 220 Swift is one of the cases that WW manufactures seasonally instead of continuously. Production setup and fine tuning is probably going to create some garbage that should have been caught but wasn't. S/F....Ken M