Bullets Getting Scratched Between Ogive & Case Mouth

[CarlGeorge]

The title describes the problem I'm trying to resolve. I'm new to the .284 and I'm pulling my hair out. (It's straight .284.) Image attached.

Some of the basics:

• Lapua 6.5-284 necked up (not turned)
• Berger 180gr Hybrid
• RCBS Rockchucker press (I bought it used 5 years ago. It's probably 20 yrs old. It has served my needs fine - but this is the first "high precision" work I've done with it. All my previous loading has been mainstream 9mm, .223, plus a variety of other calibers.)
• Redding Competition Seater Die with VLD Seating Stem.

This is the second set (brand) of dies where I've had this problem.

My current theory is that the press is out of whack.

It's hit-and-miss as to how often I get these marks. I loaded 25 tonight and probably got 5-7 that were marked in some way. I loaded 10 more and probably 5 of those were marked.

Die seems clean inside.

Anyone have any ideas?

Thanks.

CG

 

[gman47564]

what type of seating die are you using?

 

[CarlGeorge]

Redding Competition Seating Die - with VLD Seating Stem.

 

[WillyTP]

Is this only happening on the first loading of the brass?

 

[WillyTP]

Also, when you’re expanding up the neck are you using an expanding die and mandrel or with your sizing die?

 

[CarlGeorge]

Good questions.......

I had to go down and look at the 15 rounds I loaded last night. They were done using resized brass (once fired brass). None of the 15 had marks as dramatic as the picture I posted. A couple of rounds *might* have had a couple of lines. Although I'd feel better drawing a conclusion using a larger sample size than 15 rounds, I'd say it looks like the situation might be improved using resized brass. Although I have to say as I've been debugging this over the last month or so I was getting scratched bullets using resized brass before.

I'm using an expander die /mandrel to expand the mouth after sizing. (And BTW, I'm sizing - FL - with a .311 bushing.) This brass when loaded is measuring .312-.313. I've been planning on getting a .310 bushing to try it out. But that was in the spirit of general load development and I hadn't gotten to ordering it yet.

 

[Dusty Stevens]

Its hitting the inside of the die as you raise it.

 

[WillyTP]

Ok, you’re in luck. I’ve seen this a lot when I expand up 6BR cases to 30BR on an expanding die. Basically since the case is unsupported in the expanding die, the brass will “banana” to some effect. Your seating die is nice and tight and straight, hence when extracting the case from the seating die these scratches are made.

As you fire and resize the brass this will go away because the cases will be straight after being fired and resized in a FL die.

 

[Ralph Littlefield]

Are you using new bullets, or are they pulled?

 

[CarlGeorge]

New bullets.

 

[Ralph Littlefield]

The only thing that I can think of that contacts the bullet at that location is the portion of the seating die that surrounds the bullet as it is seated. It seems there must be something on that portion of the die. Tolerances in the die allow it to contact some of the bullets. If it is debris you may be able to clean it out. If it is a blemish (bur ?) it would require polishing.

 

[Ralph Littlefield]

Not sure how much of an issue this really is. Do you think it affects the accuracy of the bullets?

 

[ppaul]

I don't know about the banana theory but, if you take your seating die completely apart the sleeve that holds the case/bullet is basically a chamber. the last step down at the neck/bullet junction must be very sharp to leave those scratches. Gently polish the sharp edge, maybe 400 grit lapping compound, careful to just polish that edge. I think your problems will disappear. That's the only place that could cause those scratches. Also while your at it put a little lap compound on a bullet and polish the seating stem a little. You won't have that ring around your bullets.

 

[ppaul]

Ralph you beat me to it!

 

[coldboreshot]

The title describes the problem I'm trying to resolve. I'm new to the .284 and I'm pulling my hair out. (It's straight .284.) Image attached.

Some of the basics:

• Lapua 6.5-284 necked up (not turned)
• Berger 180gr Hybrid
• RCBS Rockchucker press (I bought it used 5 years ago. It's probably 20 yrs old. It has served my needs fine - but this is the first "high precision" work I've done with it. All my previous loading has been mainstream 9mm, .223, plus a variety of other calibers.)
• Redding Competition Seater Die with VLD Seating Stem.

This is the second set (brand) of dies where I've had this problem.

My current theory is that the press is out of whack.

It's hit-and-miss as to how often I get these marks. I loaded 25 tonight and probably got 5-7 that were marked in some way. I loaded 10 more and probably 5 of those were marked.

Die seems clean inside.

Anyone have any ideas?

Call me crazy but I would also consider how you are chamfering the inside of the necks. If you are currently using a 45 degree tool, try a VLD profile chamfer tool. Your issue may be drag on the inside edge of the brass at the neck. After I chamfer at any time, whether it be first loading or after retrimming, I follow up with a stiff nylon brush to remove any possible leftover "flash" from the tool. This may or may not work for you, hope it does, but perhaps just another avenue of pursuit.







y

Thanks.

CG

 

[Mulligan]

Ok, you’re in luck. I’ve seen this a lot when I expand up 6BR cases to 30BR on an expanding die. Basically since the case is unsupported in the expanding die, the brass will “banana” to some effect. Your seating die is nice and tight and straight, hence when extracting the case from the seating die these scratches are made.

As you fire and resize the brass this will go away because the cases will be straight after being fired and resized in a FL die.

^^^^^^^this^^^^^^^
CW

Edit
Better lube when necking up and slower precess fixed it for me.
CW

 

[Ralph Littlefield]

Ok, you’re in luck. I’ve seen this a lot when I expand up 6BR cases to 30BR on an expanding die. Basically since the case is unsupported in the expanding die, the brass will “banana” to some effect. Your seating die is nice and tight and straight, hence when extracting the case from the seating die these scratches are made.

As you fire and resize the brass this will go away because the cases will be straight after being fired and resized in a FL die.

I thought the concern was scratches on the bullet, not the case.

 

[Mulligan]

http://www.xxicsi.com/neck-up-expander-die.html

I have found these mandrels to help a bunch.
CW

 

[CarlGeorge]

Thanks. I appreciate it.

I'm wary to polish the seating sleeve because (reporting this escapade for this thread is causing me to recall some details I'd forgotten) this is the 3rd seating sleeve that has caused these issues. The first sleeve (different mfg than Redding) scratched bullets. It was returned and polished. Still made marks. They sent me a different sleeve. That made marks. Bought Redding. Now it's making marks.

I don't know if it's impacting accuracy. I haven't done sufficient testing. I've just assumed it would at longer distances, given the various minutiae we mess with to have cartridge-to-cartridge consistency. I'm just wanting to get everything settled in so I can shoot. (I'm not shooting competitively but am preparing for a variety of 500-1,000 yd shooting I'll be doing this year. The rig came together just 3 months ago and I don't feel like I've yet hit my stride with it because I've been working through these bullet issues.)

Good idea re polishing seating stem. That ring might also be coming from my bullet comparator. I'll check both.

 

[rwj]

Have you checked the alignment between the press ram and die? Angular and/or offset misalignment could allow the bullet to contact internal die surfaces.