I did a dumb thing (dumb but not dangerous)

[dgeesaman]

280AI, brass coming from Norma 280 Rem, loading for first firing as 280AI.

I did not realize the seater had a crimp feature and the Partition bullets lack a cannelure, so it was gripping the neck and pushing down for most of the rounds. I caught my mistake before seating the final ladder step but most of them now have smashed down shoulders.

What are my options? So far I can think to fire them as-is to reform the brass or scrap the brass and save the bullets, powder, and primers.

 

[dgeesaman]

I don't have the rifle here, but the diameter of the brass below the shoulder / body junction is .457. SAAMI chamber tolerance is .455 / .457 at the junction, so if it chambers it won't be loose.

 

[Dusty Stevens]

If itll chamber itll blow out

 

[joshb]

^^^^”IF”^^^^^

 

[1shot]

Shoot 'em.

 

[fkimble@charter.net]

If it won't chamber, pull the bullets, and resize. And back your seater die out a turn or two!

Frank

 

[Charlie-NY]

My vote - assuming that they won't chamber, and I doubt it - TOSS THEM!

 

[mikecr]

I caught my mistake before seating the final ladder step but most of them now have smashed down shoulders.

If there was a dumb action, IMO, it's failing to measure results as you go.
Do you seat bullets to a tested best CBTO? If so, then this takes actual measurement.

 

[dgeesaman]

If there was a dumb action, IMO, it's failing to measure results as you go.
Do you seat bullets to a tested best CBTO? If so, then this takes actual measurement.

I was measuring CBTO of the seated bullets after seating. I only measure CBTO of the brass when I’m sizing the brass. The shoulders collapsed because of the incorrect seating die setting.

 

[mikecr]

I guess I'm misunderstanding something. Collapsing shoulders didn't affect CBTO?

 

[piie]

Just rechamber your rifle to match this new Wildcat Weatherby-280AI

 

[Bill K]

If it chambers, just fire it and it will form back to chamber fit.
Then be sure and readjust your seating die to not start crimping.

 

[jackieschmidt]

I am in the camp that says if it will chamber without excessive headspace, it will fire, and if it fires, it will take the shape of the chamber.
I would put a thin film of sizing wax on the case body to insure that the case does indeed form to the full length of the chamber.

 

[dgeesaman]

I guess I'm misunderstanding something. Collapsing shoulders didn't affect CBTO?

It does, drastically.

But it happened in the seater and I don’t measure CBTO of the brass *after* seating the bullet. I switch to my 7mm comparator insert and only measure CBTO to the ogive of the seated bullet. That was not affected by the brass collapsing.

 

[brokeasajoke]

No danger of pressure to fire it? Could not the powder become a compressed load now?

 

[dgeesaman]

No danger of pressure to fire it? Could not the powder become a compressed load now?

On this load it’s nowhere near compressed.

I reckon the volume change is less than the first firing from 280 Rem to 280 AI. While the shoulder is definitely pushed down the body diameter is the same/bigger. That’s the choice where I seek others opinions.

I plan to pull and save the Partitions so that will give me a chance to back the powder off a bit. Then I’ll refire them, anneal, resize, and start again.

 

[Ray123]

They shouldn't chamber ...there is a bulge in the shoulder where the shoulder angle starts.
Pull bullets, FL resize, seat bullets hard into lands, fire form with a slightly reduced charge...and the shoulder angle will reappear...again. Crimp bullet separately next time if needed, to prevent case collapse.

 

[dgeesaman]

Ok I got my puller collet and pulled all of the bullets so I can save these precious Partitions. It occurs to me that if I load bullets and shoot them, if the necks grip first before the shoulder moves forward, then I might get a wrinkle at the shoulder and short overall length. So then it begs if I should fire from them cream of wheat style. Any thoughts on how to fire form a bigger case like this using cow? (This would be my first time fire forming without a bullet)

 

[Webster]

I was measuring CBTO of the seated bullets after seating. I only measure CBTO of the brass when I’m sizing the brass. The shoulders collapsed because of the incorrect seating die setting.

Why didn't you stop after 1 collapsed shoulder? If they chamber I would shoot them. It's like FF to a wildcat. When I FF 6BR to 6BRX the shoulder is 0.100" short. Are the bullets lined up straight without being bent out of alignment?

 

[dgeesaman]

Why didn't you stop after 1 collapsed shoulder?

I didn’t know it was happening. See previous post where I explained how it was the seating die that did this, so it wasn’t observable when I did my usual shoulder bump measurements.

The bullets sit straight. They should have plenty of jump due to mag length limits. My gut thinks the shoulder will press forward first before the neck releases the bullet, but with the .02”-ish of headspace I might need to false shoulder the neck.

David