I ran into this my self. My oal was to long. Now I check oal first before I do any thing else. Then one time I wasn't paying any attention and I turned the seating die down alittle too much. And I bulged the shoulder just a tad they wouldn't
let the bolt close. This does happen I guess this is why reloading is so much fun.
I guess what I am getting at is you can't be to careful. Get a good pad and put
reloading greaase on it roll your cases across it they go into the dies a lot easier.be sure to wipe the grease off after reloading.

I too reload for an Ruger 77mk11 270

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