284 freebore question.

[chuckbuster243]

Hello guys,
If I have a 284 win with a .220 freebore shooting the 180 Hybrid jumping .030. I should be above the donut right?
freebore .220
minus jump .030 =.190
bearing surface .459 minus freebore .190 = .269 minus neck length .285 = .016

So if my math is right... I should be 16k from neck shoulder junction. Is this enough or is my math wrong?? Thanks, Matt

 

[jkohler]

My reamer has a .212 freebore and the 180 hybrid can be jumped .050 before I get into The donut. I did Skim cut the neck but some of them did end up with a Donut.

 

[FeMan]

You should be well clear.

 

[chuckbuster243]

Thanks guys that's what I was hoping to hear.. Matt

 

[yukonal]

I'm WAY clear with a .200 fb.

 

[BradY]

I have a 220 thou freebore shehane and have found donuts to be a bit larger than expected on two firings of lapua 6.5x284 brass that has been necked up and fireformed. Im shooting a no turn chamber so have to inside neck ream the donuts out. I would say you wouldnt want to be much closer, and definitely dont want to be shooting the same jump with the VLD. If your shooting the same brass but in the more common 313 nk chamber then you will be neck turning, in which case if you cut into the shoulder sufficiently you wouldnt expect much trouble from donuts.