What’s the cause?

[4dds]

Trying to figure out what is causing this ring on the bullet I’m getting after seating. 6.5 Grendel using Lee dies and seater. I would have to double check but I believe.025 neck tension.

 

[Sig Marine]

What powder and how much? The ring is caused by the seating stem having to force the bullet to the seating depth your are trying to achieve. This said, when you say "I would have to double check but I believe .025 neck tension" could be an indicator. Also, trying to seat bullets on a highly compressed load will cause this type of ring.

 

[4dds]

30.5 of CFE223 and I may be wrong but I thought around 31 was where it started compressing this load.

 

[Namekagon]

30.5 of CFE223 and I may be wrong but I thought around 31 was where it started compressing this load.

I've had this happen on my bullets without being compressed or a neck tension issue. For me, it was the shape of the seating stem cone not matching well with the bullet. It was happening to me on an older RCBS die. I was able to fix it by polishing the rim of the seating cone with some steel wool. Nothing crazy, but it smoothed out the sharp edge of the cone just enough to stop marring bullets.

 

[4dds]

I’ll have to pull it apart and check it out. Thanks

 

[Sig Marine]

If the edge of your seating steam is sharp, the marks left are usually like a fine cut. The marks in the picture are a little different than that. Check your neck tension; most of use use .002 or so for bolt guns and .004 for gassers. If neck tension is good, you might try to lube the inside side of your case necks to ease the friction between case and bullet when seating. Only you can tell when seating bullets if you are compressing the powder too much. The usual indicators are powder crunch and harder pressure required on the press handle when seating and sometimes difficulty achieving the proper seating depth. Just curious, try seating a bullet in a case without powder and see if you get the same ring.

 

[J.Boney]

I've had this happen on my bullets without being compressed or a neck tension issue. For me, it was the shape of the seating stem cone not matching well with the bullet. It was happening to me on an older RCBS die. I was able to fix it by polishing the rim of the seating cone with some steel wool. Nothing crazy, but it smoothed out the sharp edge of the cone just enough to stop marring bullets.

This... a VLD seating stem would likely not do this. As far as I know, there isn’t one for a Lee. The Redding Competition Seater has a VLD stem, and is an awesome die.

 

[doc88]

I agree this is a seating stem issue. I had this happen with a Whidden seating die and they promptly replaced the stem at no charge. You may also check with your die maker.

 

[MtnCreek]

Could possibly be the crimp function of the seater die. Make sure the crimp part of the die is not touching the case mouth with ram fully raised.

 

[noylj]

Have Lee make a custom seating stem for that bullet. It doesn't cost much. Ask them to have the seating stem NOT touch the meplate.
Separate seating from crimping.

 

[4dds]

It doesn’t crimp just seats the bullet. I’m going to try and pull it apart this evening and see if there are any sharp edges.

 

[4dds]

Just pulled it apart and looked a 130 Berger only touches the stem where the transition from cone to straight drilled is. Which I don’t think is right and definitely explains why it’s putting the ring on them. I pulled my 223 seater apart and the stem from it seems to fit the end of the bullet much better. I’m going to try some rounds with it when I get a chance.