collet sizing die question

[Onagoth]

New to reloading here (22-250 only for now),

just tried resizing some once fired brass with my lee collet sizing die. I attached the die as the instructions indicated and began resizing the necks. I found some variation in the size of the mouths though, some would be pretty good around .254 inches, others would be larger or smaller.

I set the die properly as the instructions indicated, but it seems the neck sizing can vary?

What am I messing up here? Should I just go with a full length sizing die? I also found some variations in the neck sizing at the beginning of the shoulder.

Thanks

 

[PerversPépère]

Was that once-fired brass shot in your rifle or is it from another source?
Was your brass the same brand and lot?
Was it trimmed before?
PP.

 

[Onagoth]

Yes, fired from my rifle, not necessarily from the same lot, but its all winchester, and its not yet been trimmed.

thanks

 

[adriel]

Are you giving it consistent pressure each time and how much variation are we talking about here?