Bumped shoulders too far

[Jimbee]

I have a Tikka barrel reamed to 6-284. Long story short, when I necked down 6.5-284 brass I pushed the shoulders back .012ish. I ruined some lapua brass in this latest reloading learning experience. I had a case separate and there's a telltale shiny ring on most of the other fired pieces. I have some unfired Norma brass that I necked down and bumped shoulders too far. Can I salvage it by jamming a bullet into the lands, or do I need to start over with new?

 

[WeiserBucks]

It could probably be salvaged with jammed bullets but I would only use that brass for range work and not risk a separation during a hunt.

 

[MontyMontana]

I agree with the above post... It can be salvaged but I would probably use a fire forming load to do it.

 

[waspocrew]

Jam it or make a false shoulder to headspace off.

For a false shoulder, you’d need to neck up the brass (.264 might work, but .277 would be better), then neck back down to 6mm.

When necking back down, do it in small increments until you can chamber the brass with a decent amount of resistance.

Here’s an example with my 6.5 Sherman

 

[Pickettpuncher]

I like the false shoulder better myself, but either way can be done.

 

[WeiserBucks]

The brass is already overworked, necking it up and back down for a false shoulder is just working it more. Jam and blast or throw it away.

 

[Colorado Cowboy]

You could anneal the brass and then use a light load to fire form the case.

If it were me, I would trash the brass and start over with new cases. Lessons learned.

 

[waspocrew]

The brass is already overworked, necking it up and back down for a false shoulder is just working it more. Jam and blast or throw it away.

Overworked because the unfired brass was sized once? Pretty simple to anneal if that’s the concern.

But also pretty simple to just trash it and start over with new brass.

 

[WeiserBucks]

Pretty simple to anneal if that’s the concern.

I don't anneal so I'm not concerned

 

[Darkphage]

To answer your question. I’ve been reloading for 20+ years, and frankly imo it’s not worth it to try to “salvage” brass you have inadvertently damaged. I didn’t see you mention how many were damaged - so I’m not sure if we’re talking about 10 or 100 brass or something in between, but I would just pitch them and start again. #1 case head separation just sucks (been there done that). #2 even with annealing etc the damage mid body of the case from overworking won’t be “fixed”. #3. Will they ever be consistent with your other new properly worked brass? #4. You may always have a nagging worry about those brass which again imo I’d just rather not have.

Good luck!

 

[TaperPin]

There’s more to this story that should be looked into. How is it possible to have so much headspace a normal full length die was able to push back the shoulder so far as to cause a separation and thinning ring on every case? Sounds like the reamed barrel has excess headspace or the full length die was altered. Since it was a rechamber odds are the chamber is too deep and headspace wasn’t checked? Pressure issues immediately come to mind. How close to a published max is this? What do your primers look like?

Seating the bullets to jam or a false shoulder would be the way to fire form, but a false shoulder is better if you’re doing this for the first time since the headspace issue has to be better understood - if the .012” is the brass after it’s sprung back and the real excess headspace is larger.

 

[Jimbee]

Headspace was measured and said to be on the long side but within spec. I was attempting to neck down as much of the neck as possible and I blame my ignorance for pushing shoulders back to far. I'll probably just start over with new brass. My cousin also had a tikka barrel reamed at the same time by the same 'smith and has no issues.