neck sizing question

[jpeaston]

Guys,

I am trying to get going on a new 280 ackley I just had built, last night I was getting my new dies close in anticipation of reloading tonight, what I came across is this. Redding 3 die comp set.

It appears the necks on my Nosler brass in this chambering are really long, like longer thatn the bushing I am using. I know most guys only neck size the portion of the neck that will their bullets will be seated in. I sized one before retiring for the night and can't get down to the shoulder, the neck is going up throught the bushing and hitting the bushing pusher before getting deep enough to get down to the shoulder. My neck on this rifle is .313, the portion of the neck getting resized is getting down to .306, and the unsized portion is .310 or so, leaving a donut. What are you thoughts?

I will be reloading Barnes ttsx at .05 off lands, without doing the math I think the bullet will not be seated deep enough to be in the unsized portion of the neck, but I have never dealt with donuts like this. What should I do?

Plus I was going to trim brass after neck sizing, most of the new brass is about .013 longer than my smith recomended to trim to, and once fired brass is grew .003 in length.

 

[jpeaston]

Another thought, my loaded neck diameter should be .309, so if I figure how deep the bullet will be seated, and only neck size that portion, then seat, my previously talked about donut would almost go away, having a new step from .310 to .309, instead of the previous step of .310 to .306.

 

[SBruce]

If it really bothers you, you might call redding and ask for some longer bushings................I don't personally think that's necessary, but it might be an option if you'd rather size the whole neck.

Definately trim the cases to the length recommended. Leaving them longer than the neck portion of the chamber can result in very high pressure.

As far as the donut goes, that's not the donut we usually talk about. IMO, leaving the last little bit of neck un touched by the die helps ensure that any "real" donut is not against the bullet. I often leave the last little bit of neck un sized with a neck die, have done that for years. It doesn't hurt anything IMO.

Hope that helps