260AI neck question

[skeetlee]

I understand that if you use a 243 case and neck up to a 260 rem you will have issues with a donut forming as part of the shoulder becomes the neck. My question is if you go with a 260AI and neck up 243 cases (Lapua) will the donut issue go away? It seems to me that the 260AI has less of a neck after fire-formed. Will the donut be bown out? Thanks as always. Lee

 

[savageboy]

I have always used the .308 lapua and necked down to avoid the dreaded donut. Never had them and on my 2nd barrel. Here is a good article: http://www.6mmbr.com/gunweek046.html