Not enough chamfer?

[Beeron]

I have never seen that crimp line in brass before.
Were it me, i would run my mandrel through it and if that crimp line didn’t come out, I would likely discard that brass or at least trim til i was past it.
I would be suspicious of highly variable neck tension and runout otherwise.

 

[snooker]

I go along with more chamfer, I know you said they were below 2.045" oal, but trim them to 2.035" max.
243 are notorious for growing quickly in length.

 

[yomomma]

I have never seen that crimp line in brass before.
Were it me, i would run my mandrel through it and if that crimp line didn’t come out, I would likely discard that brass or at least trim til i was past it.
I would be suspicious of highly variable neck tension and runout otherwise.

Lee factory crimp die, more than likely.

 

[kjohn]

I chamfer with an RCBS tool.

 

[track]

You're titlle says it all, "more chamfering".

 

[jethunter]

It's like rocket science except it's chamfering. )

 

[jethunter]

Even when you chamfer, the chamfering tool can leave small burrs. A quick pass with fine steel wool will smooth that right up, in fact in most cases the steel wool by itself works well too.

 

[bearhunter]

Suther, your pics show a very common issue with reloading "FLAT BASE" bullets.

Most people don't use them and prefer the sleeker boat tail or semi boat tail types, so never see this issue.

I load a lot of flat base bullets and learned my lesson the hard way, from loading flat base bullets into straight wall pistol cases, "flare the case mouth" or cut a deep chamfer.

When you withdraw the expander ball from your case mouth, it drags a bit of case metal with it, not much but enough to create a sharp edge.

A sharp edge will be created after case trimming as well.

As for that "crimp" line on your cases, IMHO, those should be removed as much as possible before the case is reloaded.

 

[Suther]

I go along with more chamfer, I know you said they were below 2.045" oal, but trim them to 2.035" max.
243 are notorious for growing quickly in length.

I will trim them shorter than 2.045 when they need trimming, but these are 1f from factory ammo and my book lists 2.045 as the max length and they haven't hit that yet.

 

[Suther]

Suther, your pics show a very common issue with reloading "FLAT BASE" bullets.

Most people don't use them and prefer the sleeker boat tail or semi boat tail types, so never see this issue.

I load a lot of flat base bullets and learned my lesson the hard way, from loading flat base bullets into straight wall pistol cases, "flare the case mouth" or cut a deep chamfer.

When you withdraw the expander ball from your case mouth, it drags a bit of case metal with it, not much but enough to create a sharp edge.

A sharp edge will be created after case trimming as well.

As for that "crimp" line on your cases, IMHO, those should be removed as much as possible before the case is reloaded.

Yeah I've loaded a few flatbase bullets before, but nothing as small in diameter as 6mm and nothing with an edge this sharp. 7mm speer hotcors and 277cal Winchester power points both have a more rounded edge at the base.

I'm also aware of the need to flare the case mouth on pistol/straight wall brass. Obviously I wasn't expecting to need that for bottle neck rifle, but I'm always happy to learn.

As for the crimp marks, I'll keep that in mind. Never put a lot of thought into the crimp marks being a potential source of problems.

 

[Suther]

Lee factory crimp die, more than likely.

Nope. Factory crimp from Remington.

 

[cosmic]

Well - Its pretty simple. If its copper shavings, you need to chamfer the case. If its brass, the factory over crimped the case mouth to the point where the wall thickness was paper thin, causing it to collapse during the reloading process.