Rolling Shoulders

idcwby

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Jun 23, 2015
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I'm using a RCBS Gold Medal seating die. 300RUM ADG case and a 240gr Alco bullet. The first one went in without any trouble, than the next two did this. I've never seen this before, was wondering what the cause would be? Bullets have a coating of HbN.

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What was your I.D. on the neck? Picture looks like you did not chamfer the neck, maybe you did. I had a similar problem with 5.56 rounds. They had very slight rolled shoulders, and I did not catch it until after several rounds. VLD chamfer tool helps also. I have never worked with ALCO bullets, so it could be something else.
 
What was your I.D. on the neck? Picture looks like you did not chamfer the neck, maybe you did. I had a similar problem with 5.56 rounds. They had very slight rolled shoulders, and I did not catch it until after several rounds. VLD chamfer tool helps also. I have never worked with ALCO bullets, so it could be something else.
Neck was chamfered with vld style. My calipers are not the best for trying to measure neck I.D. I'm figuring out. Ran a case through the resize die and it was a snug fit for new brass. All the bullets are measuring at .308" or slightly smaller.
 
Following. I had some HbN coated 140 grain Nosler Accubonds do the same thing in three out of ten 6.5 Creedmoor cases recently. Cases were once fired, trimmed and chamfered. I had guessed that the HbN would be enough of a lubricant, and did not add additional dry lube.
 
It almost looks like your seating stem is not low enough and it is pushing the case too far into the die to where something else is making contact as well. Can you lower the stem and raise the die?
When I first got this die, I smashed a few necks from not having the die setup correctly, that was a fun lesson.🤦‍♂️ I got the stem as low as possible and die high as possible now.
 
Were these virgin cases?
Maybe some graphite or dry lube if you have it.
I do not have the tools to measure but my ADG necks have been pretty tight.
Virgin cases, the bullets have HbN so I figured they would be good enough lube and I didn't have any issues with the same lot of brass and loading 212ELDXs.
 
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