Ring around bullet caused by seater die

M

Machineguntony

New member
I just got into reloading for accuracy. Today I had my 308 MatchKings arrive, so I started loading up an experimental batch.

I noticed that my searing die (Dillon) was leaving this slight scratch around the bullet. See pic.

I took apart the die and saw the the ring is caused by where the bullet contacts the seater part of the seating die. I checked the bullet before seating, and it's definitely caused by the place where the bullet contacts the seater part of the searing die.

Will this affect accuracy? It can't be good for accuracy, I'd imagine.

I also checked my RCBS seater die, and I noticed the same connection point between the seater and the bullet point of contact.

Is there a way to prevent this ring? Should I use a match grade seater die?

What do you guys do?

 
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Maybe it's me but I can't see any deformation in the jacket. If it wasn't for the arrow I probably wouldn't have spotted it.

Are you chamfering your mouths? If you could ease seating I bet that would help. If you use imperial or a similar sizing wax, leave it on for the seating

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Not abnormal to have a trace of the seater stem on the bullet nose. If the bullet is somehow deformed, then you might have to worry, and aforementioned methods to reduce seating tension might be in order. From the pic, it appears only to be a trace or outline, should not affect accuracy.
 
Hah! that's normal , if you think about it the seater button has to make contact ( somewhere ) with the projectile so it's going to leave a slight "mark" .
I can barely see that ring ,, load em up and let em rip,,,,:)
 
I just spoke with Forster. They now have heat treated Nitrite coated seater stems.
I had called them 10 years ago and said I was deburring the deburr [under the microscope with spinning stem and sandpaper on a stick technology].

Some guys glass bed the seater stem to a particular bullet.
Everything else is misfit compromise when the concave stem touches the convex bullet.
The best one can hope for is smooth on smooth so the bullet does not get a ring, or worse yet, bullet stuck in the seater.
 
I am not a member of the 'be kind to your bullet club'; I have seating dies with 5 different seater plugs, if I do not like what one die does to my bullets I change dies.

And then there is the 'be kind to your bullet' club, why be kind to it if you are going to chamber it and then his it with 60,000 psi. And then there is that part about 'off the lands'; I want the running start, think about it.

And then there is that part about seating effort and bullet hold; most are exempt because they use neck tension.

F. Guffey
 
The ring is caused by a slightly sharp edge on the mouth of the seater. Non issue unless you are entirely anal retentive. You could always pull the seater and very gently polish the lip. Otherwise a little time and a few hundred bullets will smooth it off for you.
 
With that little mark being concentric, and every bullet having that little mark, there really cant possible be very much impact on consistency, hence accuracy,
 
My hornady seater was doing a bit worse to my berger VLDs. Some of those bullets went out and produced some amazingly small groups. As others have said not an issue.
 
Don't worry about that ring. Last year I pulled a couple hundred cup and core 223 bullets (Nosler BT), using a collet-type puller. The puller left a real dent around the bullet, and I was sure they'd be worthless for accuracy. But, since the grandkids run through a lot of my ammo, I went ahead and loaded them up with my standard accuracy load and put them aside for future plinking use. I found later that they were just as accurate, or at least so close that it was hard to say they weren't.
 
Bullet accuracy is most affected by tail imperfections and obvious imbalance issues, and least by nose imperfections. The slight ring is not an issue as others have said.

Jimro
 
I know, but it bothered me, so I hit the seating plug with a deburring cutter and put enough of a cone at the mouth of the plug cavity to spread the load over a band of the ogive. No more marks.
 
As the others said, there's no ballistic consequence. The reason is that the depth of the mark is way shallower than the height of the air boundary layer over the bullet in flight. It's the same reason rifling marks don't adversely affect ballistic coefficient, and your mark is much more shallow than a rifling mark.

My expensive Redding Competition Seater Dies do the same thing. I've seen the same marks on some commercial loads, too. They make one seater ram with the idea it will catch all their bullets on the ogive before the tip can contact anything and will center it much better than tip contact does, tending to seat bullets straighter. Forster will make custom seaters if you send them a bullet to match. But I don't really see a point. As already mentioned, you can remove the seater stem and spin it in a variable speed drill (or your lathe if you have one) while applying polish or fine sandpaper followed by polish. I'd use a Dremel with those rubberized abrasive polishing tips if I were doing it. So far, I haven't felt the need.
 
Machineguntony
Its caued by the resistance form the case when seating the bullet , as someone posted bevel the case mouth. I would add , before you size , lightly lube the inside of the necks with a Q - tip.
Sorry I had to ask. Your brass is tumbled cleaned first ? I hope . Should be using the expander ball on your sizing die, or your bullet is acting as the expander. That light ring wouldn't cause accuracy problems . If you use 0000 steel wool , a few spins the mark would be gone. Your reloading for accuracy. Are you a benchrest shooter.? Do you check for case headspace & runout.? What rifle are you reloading for.?
 
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I understand your concerns, the people on this forum will get you the answers. Everyone has been always very helpful to me. They turned me into a accuracy nut. Always checking this forum for good conversation. Keep it coming. Thanks Chris
 
I shot the rounds tonight. These were the results.

100 yards on a rest. There was some human variance, as I couldn't get the rifle totally rested on the Caldwell bags.

The MatchKings are definitely more accurate than the bullets I use in my belt feds.





How does one measure group size? Is it measured from the widest point from the outside of the bullet diameter?



Chris, I'm reloading for a Remington 700 PSP. My first bolt gun in like 20 years! I'm enjoying the shooting sports.

 
I'm quite impressed, being as you haven't fired such a rifle in a long time, and shooting with equipment that wasn't working for you too well.
 
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