Die to press alignment

[jimbires]

Mark , what is the runout on a fired case , before you do anything to it ?

 

[TackDriver284]

Mark , what is the runout on a fired case , before you do anything to it ?

Good that you brought it up, measured 6 fired .308 Lapua cases, they all measured .0005" or less. Mostly barely any movement on the dial indicator.

 

[IdahoCTD]

Just for giggles...if you have a non bushing die size a case in it and measure runout prior to a expander and after. I'd also be curious about your bullet runout after seating bullets in those .003 out cases.

 

[TackDriver284]

Just for giggles...if you have a non bushing die size a case in it and measure runout prior to a expander and after. I'd also be curious about your bullet runout after seating bullets in those .003 out cases.

Yes, minds think alike, I was looking around for a 308 die without the bushing and found a RCBS die from like 20 years ago. I'll clean that one up and size a few pieces and see what the readings are.

 

[phil]

Yes, minds think alike, I was looking around for a 308 die without the bushing and found a RCBS die from like 20 years ago. I'll clean that one up and size a few pieces and see what the readings are.

If you have a doubt get one chucked up and put a needle on it. If it’s reamed straight….i guess that would eliminate one thing. I’m sure there is a way to check shell holder vs die thread alignment.
It never ends…

 

[jimbires]

try the standard die , nothing to lose by trying it .

back to the bushing die . I'd next try it without a bushing . if the runout is good , I'd try it with a bigger bushing . if runout is good , I'd try putting the correct bushing in .

 

[mjcmichigan]

No, sorry for not being clear in the first place, I meant just the sized case neck on a RCBS CaseMaster to check neck runout, without the bullet seated in it. As for the expander, I never liked them for the reason you gave, I removed them all from my dies, I use a Sinclair carbide expanding mandrel as a 2nd step after sizing. I use an expanding mandrel .001" under bullet diameter, like a .307 mandrel for the .308 cases. I keep most of my neck tension to .001" , but I also have .002" mandrels.

Thanks for the clarification. My mandrel (Wilson) are all 0.001” undersized. I might have been better off buying a different brand as some allow for 0.0005” increments

 

[phil]

Thanks for the clarification. My mandrel (Wilson) are all 0.001” undersized. I might have been better off buying a different brand as some allow for 0.0005” increments

I’ve had good results with 21st Century. Most of the time it’s not so critical but sometimes it sure is.