Gunsmithing First five shots, What to look for?

[tacticalpanda]

Was at a gunsmith yesterday getting my first bolt/precision rifle headspaced. I'm pretty new to rifle shooting outside of ARs. He told me that if you look at the first five cases from your first five shot you can learn a lot about your rifle but didn't elaborate to much just talked about looking to see if there are stress marks close to the rim to see if the bullet is being seated enough and something about a smashed primer. Pressed him a little bit but didn't seem like he really wanted to get into it.

Anyone here able to elaborate on what I should be looking for?

 

[Ledzep]

Yeah things to look out for:

Bulges (Chamber cut wrong)
light colored rings around the case, usually ~1/4-1/2" forward of the rim. (case is about to split into 2 peices, front and back-- worn case usually from several reloads and excessive resizing)
Cracks (bad brass or hot loads or loose chamber or a combination)
big scratches/gouges (Chamber or feed mechanism issues)
flattened primers (hot load or undersized chamber)
primer "cratering" (Warm load or loose firing pin/firing pin hole fit on the bolt face)
peirced primers (Hot load or excessive firing pin protrusion or sharp/burred firing pin)
blown primers (HOT load)
Primers backed out of case (headspace too long)
stuck bolt (short chamber or hot loads)

Might not hurt to grab a reloading manual or three and read through them. Maybe even start reloading.

I'm sure there's more than what I've listed, too.

 

[tacticalpanda]

Yeah things to look out for:

Bulges (Chamber cut wrong)
light colored rings around the case, usually ~1/4-1/2" forward of the rim. (case is about to split into 2 peices, front and back-- worn case usually from several reloads and excessive resizing)
Cracks (bad brass or hot loads or loose chamber or a combination)
big scratches/gouges (Chamber or feed mechanism issues)
flattened primers (hot load or undersized chamber)
primer "cratering" (Warm load or loose firing pin/firing pin hole fit on the bolt face)
peirced primers (Hot load or excessive firing pin protrusion or sharp/burred firing pin)
blown primers (HOT load)
Primers backed out of case (headspace too long)
stuck bolt (short chamber or hot loads)

Might not hurt to grab a reloading manual or three and read through them. Maybe even start reloading.

I'm sure there's more than what I've listed, too.

Great list. Thanks.

My shooting club has a reloading seminar coming up soon that I'm planning on taking.

Will pick up a manual this week and read through it before hand.