Case mouth bells after bullet seating

[Clownbuster]

Loaded up 30 rounds of 3rd fired, neck-turned to 0.015", trimmed to length, mouths de-burred / chamfered, annealed, sized thru Redding Type S Bushing die, Berger 180 gr seated with Redding Comp. seating die.

Loaded diameter measures .311" at mid-neck, belled-out case mouth measures .321".

Obviously won't chamber...
Pulled bullet, nice and smooth, nothing shaved off...

What's happening?

Only thing I can think is over-annealed and the end of the case mouth is too soft?

 

[Juma]

Did you bounce the die when seating. That can cause this.

 

[pmclaine]

If you are belling that much you may need to slightly taper crimp just to "iron" the bell back flat.

I load on a Dillon S1050

I dont really bell before seating.

I do chamfer inside/outside the neck which allows my boat tail bullets to neatly slip in to the neck with enough grip no crimp or "ironing" is required.

I would start with backing off the "bell" feature of your reloading set up.

Edit/Add - On further review with what you do to your brass it appears you are loading single stage and belling is not part of your process.

Ill just leave my nonsense here in order to follow and educate myself.

 

[PinesAndProjectiles]

What's your trim length? Is the seating stem bottoming out on the case mouth?

 

[Clownbuster]

Did you bounce the die when seating. That can cause this.

Juma,
Can you explain bouncing the die? Good chance I might if I knew what that meant.
Thanks
S. Grasseth

 

[Clownbuster]

What's your trim length? Is the seating stem bottoming out on the case mouth?

Trim length is 2.08", cases were trimmed to 2.072.
Is it possible to bottom out like that with the Competition Micrometer Seater Die?

 

[mdmp5]

I would start with backing off the "bell" feature of your reloading set up.

Pmclaine I’m pretty sure he isn’t running a belling die of any sort; he’s loading 7mm with boat tails and there would be absolutely no reason to do that

 

[mdmp5]

Trim length is 2.08", cases were trimmed to 2.072.
Is it possible to bottom out like that with the Competition Micrometer Seater Die?

With that die, what usually will happen is the die body will make contact with the shell plate and prevent any more of the case going into the die, so that’s unlikely

 

[mdmp5]

Did you try partially seating the bullet by raising the ram halfway or less and inspecting the cartridge?

 

[mdmp5]

In other words, find out when exactly the belling starts

 

[KZP]

Trim length is 2.08", cases were trimmed to 2.072.
Is it possible to bottom out like that with the Competition Micrometer Seater Die?

As a test, try trimming a single case to 1.95 and load a bullet. If it still causes this problem at that length, I'd say it is safe to assume it isn't bottoming out in the seating die.

 

[Clownbuster]

Did you try partially seating the bullet by raising the ram halfway or less and inspecting the cartridge?

GUILTY
Is that what Juma was referring to as "bouncing the die"?

 

[Milo 2.5]

I'd anneal 3-5 pcs and see if it goes away. I'd almost bet you could see it on your brass coming out of the sizing die.

 

[MtnCreek]

I'd turn the seater die out a little then re-set depth with the stem.

 

[Clownbuster]

During seating, I will send the case and bullet up into the die initially, just gently enough to get the boat tail uniform into the mouth and the bullet straight and aligned with the case before sending the assembly into the die for seating.
After over 1500 successful loaded rounds like this, I'm at a loss to what I'm doing wrong now.

 

[Clownbuster]

Thanks guys, I'll give these ideas a go tonight and get back to you.

 

[nativecat01]

I had the same problem and finaly discovered my chamfering tool was rolling the edge over instead of cutting

 

[mdmp5]

GUILTY
Is that what Juma was referring to as "bouncing the die"?

I’m actually unsure of what exactly he meant as I’ve never heard this term used before but he might have been referring to hitting the shellplate which would never cause this with the seating die. I use a small cam over every time when seating

 

[bjay]

Neck too tight?

 

[pmclaine]

Pmclaine I’m pretty sure he isn’t running a belling die of any sort; he’s loading 7mm with boat tails and there would be absolutely no reason to do that

A closer read of his post indicated to me that he was running single stage.

Hence I offered the mea culpa at the bottom of my post immediately after posting.

Had i used better reading comprehension I would have figured it out.

On a progressive such as S1050 there is brass modification to accept the bullet which the taper crimp later removes. I dont run mine that way but its there.

 

[mdmp5]

A closer read of his post indicated to me that he was running single stage.

Hence I offered the mea culpa at the bottom of my post immediately after posting.

Had i used better reading comprehension I would have figured it out.

On a progressive such as S1050 there is brass modification to accept the bullet which the taper crimp later removes. I dont run mine that way but its there.

I’m a moron. I can’t tell you how many times I miss things written after the point I was introjecting on because I see it and immediately start throwing in my 2 cents. Ugh

 

[pmclaine]

I’m a moron. I can’t tell you how many times I miss things written after the point I was introjecting on because I see it and immediately start throwing in my 2 cents. Ugh

Our minds are so fast and sharp that they engage the keyboard at lightspeed.

Just a sign of above average intelligence, congratulations to you and I.

 

[mdmp5]

Our minds are so fast and sharp that they engage the keyboard at lightspeed.

Just a sign of above average intelligence, congratulations to you and I.

I take it you’re a glass half full kinda guy

 

[MtnCreek]

Minds engaged or fingers? :-D

 

[Clownbuster]

I had the same problem and finaly discovered my chamfering tool was rolling the edge over instead of cutting

Yes sir, I thought about that too, but I hand deburr the outside mouth with a new Wilson tool and inside chamfer the mouths with a new Sinclair 28° VLD tool, while watching under a big magnifying glass.

 

[Clownbuster]

Our minds are so fast and sharp that they engage the keyboard at lightspeed.

Just a sign of above average intelligence, congratulations to you and I.

I've been known to "ready, fire, aim" myself boys, and appreciate the help. Course correction lol.

 

[pmclaine]

I take it you’re a glass half full kinda guy

Locke or Malthus?

 

[Clownbuster]

Neck too tight?

Hey bjay, thanks for chiming in. Maybe??...BUT I've seated over a thousand of these rounds before with this setup without any issue. The only change I made was I annealed the cases before I sized them.

 

[bjay]

Hey bjay, thanks for chiming in. Maybe??...BUT I've seated over a thousand of these rounds before with this setup without any issue. The only change I made was I annealed the cases before I sized them.

I also see this with my 300nm when doing more than 4k neck tension and not trimming before seating bullets(i use giraud trimmer that also chamfer and deburr)
But not as crazy as yours

 

[Clownbuster]

Problem found thanks to TimK on here. SS tumbling too long will cause a "lip" to develop at the end of the case mouth. I've never ran my brass longer than two hours before in the SS tumbler; this last time was over 5 as I lost track of time and forgot about it...

Virgin brass: measured at the very end of the case mouth with jaw calipers: 0.015"

3rd fired/processed brass: Pulled the bullets and measured the very end of the case mouth my jaw calipers: 0.021".

That's why I missed it, I was using my tube micrometer measuring the middle of the case neck, not the end...sheesh...

Thanks TimK for the win, and thanks to all for helping out. Fun to learn to stuff

 

[supercorndogs]

I’m actually unsure of what exactly he meant as I’ve never heard this term used before but he might have been referring to hitting the shellplate which would never cause this with the seating die. I use a small cam over every time when seating

None of my seating dies come close to the shell plate before they hit the case.

 

[Clownbuster]

 

[mdmp5]

None of my seating dies come close to the shell plate before they hit the case.

I’ll have to take a picture

 

[supercorndogs]

I’ll have to take a picture

I bet you talking 550 {something I have no experience with} and I am talking shell holder.

 

[mdmp5]

I bet you talking 550 {something I have no experience with} and I am talking shell holder.

No, I am using a T7 with a cam over, both sizing and seating. I meant shell holder, not plate

 

[supercorndogs]

No, I am using a T7 with a cam over, both sizing and seating. I meant shell holder, not plate

I was trying to look it up but I can't find anything. If you want to post pics of how it works, or PM them. I am interested.