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wncchester · February 4, 2012, 02:26 PM

Naw Jason, you didn't even come close to any harm. Your case suggests a full but certainly not excessive charge.

Your primer blew out at the radius of the cup due to a defect in the cup itself - such cup blow outs aren't common but they really aren't all that rare either - therefore, it is NOT an indicator of excessive pressure. You may experience a few more from that manufactoring lot number so if you take that blown primer/case and the remainder of your primers back to your dealer you should be able to get them exchanged. Or do what I do with them, use that batch of primers in lower pressure ammo for lever rifles.

The blackened ring around the primer pocket is the result of the released gases. The unsightly burn pit and circle the hot gas cut in your bolt face is cosmetic, it will make no difference in the safety or accuracy of your rifle.

The crimp marks on your case mouths are from the original factory loading. I've never seen those crimp marks dissappear even after several reloading cycles.

The live cartridge sitting in your Wilson gage looks about like what I would expect with a new factory round, meaning if it's a new or previously neck sized case it's unlikely to produce a head seperation in the next firing. Just shoot it and adjust your FL die properly next time.

Your nice 'drop in' Wilson case gage only tells you if your ammo matches SAAMI tolerances and will work in any chamber ever made in that caliber but it certainly isn't a way to gage your handloaded ammo for a precise custom fit. For that, get a Hornady LnL case "headspace" gage that fits on the jaws of a precision dial caliper to measure your 'before' and 'after' FL resized shoulder locations - there is no reason to move the shoulder back passed the fired location for bolt rifles and doing it that way insures you will have the least possible case stretching. (Other gages can do the same thing but Hornady's is the most versatile and cost effective.)

Headspace is in the chamber as it's built by the maker; reloaders can't do anything about headspace. However, it is very rare that the actual headspace means anything to a reloader who knows what he's doing even if it's 'excessive' because he adjusts for it. What we have loosely come to call adjusting our 'cartridge headspace' is no more than resizing our case shoulders to fit the headspace we have. (And we do it the same way for all bottleneck cases, no matter if they have a rim or belt.)

Excellant photos, by the way.

February 4, 2012, 02:26 PM	#15
wncchester Senior Member Join Date: December 1, 2002 Posts: 2,832	Naw Jason, you didn't even come close to any harm. Your case suggests a full but certainly not excessive charge. Your primer blew out at the radius of the cup due to a defect in the cup itself - such cup blow outs aren't common but they really aren't all that rare either - therefore, it is NOT an indicator of excessive pressure. You may experience a few more from that manufactoring lot number so if you take that blown primer/case and the remainder of your primers back to your dealer you should be able to get them exchanged. Or do what I do with them, use that batch of primers in lower pressure ammo for lever rifles. The blackened ring around the primer pocket is the result of the released gases. The unsightly burn pit and circle the hot gas cut in your bolt face is cosmetic, it will make no difference in the safety or accuracy of your rifle. The crimp marks on your case mouths are from the original factory loading. I've never seen those crimp marks dissappear even after several reloading cycles. The live cartridge sitting in your Wilson gage looks about like what I would expect with a new factory round, meaning if it's a new or previously neck sized case it's unlikely to produce a head seperation in the next firing. Just shoot it and adjust your FL die properly next time. Your nice 'drop in' Wilson case gage only tells you if your ammo matches SAAMI tolerances and will work in any chamber ever made in that caliber but it certainly isn't a way to gage your handloaded ammo for a precise custom fit. For that, get a Hornady LnL case "headspace" gage that fits on the jaws of a precision dial caliper to measure your 'before' and 'after' FL resized shoulder locations - there is no reason to move the shoulder back passed the fired location for bolt rifles and doing it that way insures you will have the least possible case stretching. (Other gages can do the same thing but Hornady's is the most versatile and cost effective.) Headspace is in the chamber as it's built by the maker; reloaders can't do anything about headspace. However, it is very rare that the actual headspace means anything to a reloader who knows what he's doing even if it's 'excessive' because he adjusts for it. What we have loosely come to call adjusting our 'cartridge headspace' is no more than resizing our case shoulders to fit the headspace we have. (And we do it the same way for all bottleneck cases, no matter if they have a rim or belt.) Excellant photos, by the way. Last edited by wncchester; February 4, 2012 at 02:37 PM.