So I’ve mentioned here that I’m fairly new to reloading precision rifle rounds. I’m about a year into this now and while I’m settled on some best practices with the 6Creed Peterson brass I was using, I screwed up with a new batch of Lapua and want to get some opinions on just how bad this screwup is. Maybe someone else can learn from this experience.
I forgot that Lapua small primer brass uses a small flash hole. I noticed a bit of “stiction” when I was running it all through the sizing die for the first time. At the 50 case mark I remembered the old reloading adage, “if something doesn’t feel right, check”. (Yes, I’m scatter brained and it took me to till the 50 case mark for the lightbulb to turn on) So I pulled the bushing thinking maybe it was hanging briefly on the leading edge and that wasn’t the case. I then checked the primer pocket under my microscope (I’m a firearms engraver and have a scope on my bench) and that’s when I noticed a bulge in the edge of the flash hole. That’s was the ah ha moment. I realized my decapping pin wasn’t large enough to break but was small enough to basically swage out the flash holes.
I then uniformed the pocket side of the flash holes to remove any bur edge. So now I basically have Lapua small primer brass with a large flash hole.
So... I ran a few rounds and group size was a bit bigger with the new Berger’s I was shooting that day for the first time. this was only with the first seating depth I tried. ES/SDs were consistent with my Peterson or close enough.
So here’s my question. Is there any issue running small primer brass with the larger flash hole. Or have I ruined any chance for an accurate round. I ask because I read something about higher accuracy potential with small flash holes. If there’s enough difference I’ll simply use this for practice stuff and order a new batch of brass.
I forgot that Lapua small primer brass uses a small flash hole. I noticed a bit of “stiction” when I was running it all through the sizing die for the first time. At the 50 case mark I remembered the old reloading adage, “if something doesn’t feel right, check”. (Yes, I’m scatter brained and it took me to till the 50 case mark for the lightbulb to turn on) So I pulled the bushing thinking maybe it was hanging briefly on the leading edge and that wasn’t the case. I then checked the primer pocket under my microscope (I’m a firearms engraver and have a scope on my bench) and that’s when I noticed a bulge in the edge of the flash hole. That’s was the ah ha moment. I realized my decapping pin wasn’t large enough to break but was small enough to basically swage out the flash holes.
I then uniformed the pocket side of the flash holes to remove any bur edge. So now I basically have Lapua small primer brass with a large flash hole.
So... I ran a few rounds and group size was a bit bigger with the new Berger’s I was shooting that day for the first time. this was only with the first seating depth I tried. ES/SDs were consistent with my Peterson or close enough.
So here’s my question. Is there any issue running small primer brass with the larger flash hole. Or have I ruined any chance for an accurate round. I ask because I read something about higher accuracy potential with small flash holes. If there’s enough difference I’ll simply use this for practice stuff and order a new batch of brass.
