Ridges on case neck after sizing

[drglock]

This is new Lapua brass with a new RCBS neck sizing die . Just running them through the die to make sure there are not dents in the case mouth .

 

[jsthntn247]

Take the depriming stem out. Get a brush a little smaller than the neck diameter of your cases. Wrap a cleaning patch on it and put some flitz, jb, or aluminum polish on the patch and run it up and down in the neck area of the case. You've got a brass build up in there, it will polish right out. Necks on new brass are freshly annealed and sticky and will come off in the die and create those ridges.

 

[Comrade Terry]

Unless I use powdered graphite for a lubricant, I get longitudinal lines like that.

 

[bigedp51]

The dies transition from the shoulder of the die to the neck is rough and scratching your case necks. Chuck the appropriate size shot gun cleaning mop in a drill and apply some J&B bore paste, Flitz polish, automotive rubbing compound etc. and polish the die, while moving the mop back and forth.

RCBS did a bad job polishing the new die 'BUT" this can happen with any manufacture, return it or polish it, its your call.

I had this happen with a new Forster die and polishing fixed the problem.

 

[drglock]

Thanks for the input guys. I'll try using some flitz

 

[bigedp51]

Second posting down by 243winxb has a good photo, and as you can see from the other postings many people with the same problem sent the die back to RCBS.

Why are there these marks on brass
http://www.ar15.com/archive/topic.html?b=6&f=42&t=375961

 

[6xcshooter]

I've gotten these from redding bushing dies also.

 

[Richard Jones]

I've gotten these from redding bushing dies also.

And Sinclair......

 

[Sniper338]

I get em with redding dies and bushings... i can only narrow it down to the inside of the bushing... nothing else sizes the necks... ive thought about trying to polish the bushing... not sure if nitrate bushing do this too or not though..

 

[ballison]

There is nothing wrong with your dies or brass. I get that on virgin Lapua 308, 22-250, and 260 brass using Redding, RCBS, and Whidden dies. I called Lapua and Redding, and it has something to do with Lapua brass being soft (if I remember correctly). It will go away after the first firing.

 

[MagnumManiac]

Was the die cleaned by you before the first use? Polishing compound is often left behind in the die, which is why you need to clean them with a good solvent before use. Polishing the neck will fix it.

Cheers.
8)

 

[ireload2]

1. Clean new dies well before use
2. Use lube so your brass does not gall (cold weld) and stick to the die.

Once you have that problem you have brass particles stuck to the inside of the die. You have to polish them out of the die. I use 400 to 600 grit wet or dry paper used wet with a light gun oil, WD-40 or similar. Polish about a minute in a lathe if you have one. Hand polishing will take a little longer. If you have a lot of brass stuck to the die, Hoppe's will take a lot of it out if you pack it with wet cleaning patches and let it sit wet with Hoppe's a day or two.

If you still get galling when properly lubricated then the die was not well polished and needs to be replaced or reworked.

 

[drglock]

Took a nylon brush and used flitz and my dewalt and problem solved.

Thanks for the help

Tony

 

[fguffey]

new Lapua brass with a new RCBS neck sizing die

I do not have Lapua brass, I do have RCBS dies, Full length sizing, Small Base sizing, BAR dies, forming dies etc.. I have never had a die damage the neck like the ones pictured. I have new unfired cases, I have never found it necessary to neck size and or full length size new cases. I do not carry my cases in a bag.

F. Guffey

 

[bigedp51]

Took a nylon brush and used flitz and my dewalt and problem solved.

Thanks for the help

Tony

I never had this happen until I bought some newer dies, in the old days the new dies were sprayed/dipped/covered with a preservative oil. Some of the new dies have a dry protective film applied and if not cleaned properly the manufacturing grit, shavings, etc will remain inside and scratch the case. Meaning the dry film is much harder to remove and even if it doesn't scratch your dies if not "TOTALLY" removed it requires more force to size the case. One die manufacture in the instructions said to clean the die with Hoppes #9 or other bore solvents. And I can tell you that odorless mineral spirits did not totally remove this dry film inside the die.

As a side note I had a RCBS 30-06 die that has sat forgotten for years and when I got it out again it had some very light rust in a few places. I took the die apart and put it in my vibratory case cleaner with treated walnut media and let it vibrate overnight. In the morning the die looked better than new and was polished inside on out and ready for action.

 

[GNERGY]

This subject has been talked about before with Lapua brass. It is the brass NOT your die, untill you size new Lapua brass, then you get the lines. Even if you polish your die and size some more new brass it will happen again.
You can either run your brass in your polisher for a while or wipe the necks with some sort of cleaner ( I have used alcohol or lacquer thinner ) then you won't get the lines. This drove me crazy for a while till I figured it out and I wasn't the only one.
Tarey
Just try it. ;D

 

[sparky123321]

I always figured it was from the polishing media I used. Figured the grit in the media left on the brass was scratching or embedding in the neck sizing portion of the die. Didn't seem to have the problem after switching over to SS pins and some new dies/bushings. That is until recently when I got lazy and used the vibratory case clean with corncob and a little bit of Cabelas liquid polish.

 

[bigedp51]

This subject has been talked about before with Lapua brass. It is the brass NOT your die, untill you size new Lapua brass, then you get the lines. Even if you polish your die and size some more new brass it will happen again.
You can either run your brass in your polisher for a while or wipe the necks with some sort of cleaner ( I have used alcohol or lacquer thinner ) then you won't get the lines. This drove me crazy for a while till I figured it out and I wasn't the only one.
Tarey
Just try it. ;D

I got the scratches and marks on my cases and they were not Lapua brass, so there goes the Lapua theory. :

 

[GNERGY]

I don't know about you but I only got them with new Lapua brass. I know what works for me, you guys can do what ever you want.
Tarey

 

[ireload2]

I have had the lines with non Lapua brass and it was always a problem with the die.

But then again I never size new brass other than to expand the neck to round out the dents.
FL sizing new brass is pretty much a waste of time.