Scratches on brass

[358Scout]

Have new 243 barrel, new Lapua brass and Redding competition neck dies. Was loading 100 Sierra SBT to break in the barrel. OAL is according to Sierra's loading manual. They wont chamber. And when you extract the case - their all scratched all the way around. I'm going to take it back to the gunsmith next week. But I was just thinking. He did a test fire with federal brass and it was not scratched. Possibly the brass is over sized. Would it be advisable to run the lot of brass through a full length case sizer first?

 

[maynard]

Why don't you try to full length resize one or two cases? Just a thought?

 

[John Y Cannuck]

Full length size first. You may have a very accurate rifle, don't mess with it until you know.

 

[Splatter]

Full-length resize and clean the chamber!

 

[Splatter]

So... what happened here?

 

[Breaker61]

Even new brass needs to be full lenght sized. You can neck size after the first firing.

 

[Splatter]

OK, so a month after the original post... any news?

 

[Eagleye]

I would be a bit PO'd if I found out that my new Lapua brass needed FL sizing to chamber in my rifle. Eagleye.