A little Confirmation, Please...

[Webster]

So, I bought a 6PPC rifle from a local gunsmith. Well known locally and has won a ton of local BR matches: short (100 & 200), mid and long range. Remington 700 action with a Bartlein barrel that he chambered. Had 100 cases of Lapua already Fire formed and 21 that he loaded for the rifle (the cases didn’t look fresh to me). He made it to shoot this year, but health issues caused the sale.
I had a couple of issues getting started. Scope issue 1st time at the range. 2nd trip to the range, I shot 2 or 3 then a case stuck and made that a short trip. After the stuck case I pulled the rest of the pre-loaded ammo and reloaded my own.
I started a 27.0 of VV n133, 64 gn Column Bergers .020 off the lands, with .003 of neck tension. Shot (2) at 27.0; 27.5; then (3) at 28.0; 28.3; 28.6; 28.9. At 29.2 I had a pierced primer.
At home I started trying to figure out my issue. The fellow I bought the rifle from said that the barrel had a .263 neck and the cases were turned to give a .260 neck loaded. The ammo is .260 loaded and after checking my spent casings, so is the neck on the barrel. The bore, chamber, lugs, everything had been properly cleaned and prepped to shoot. I have added a couple of pictures. One loaded with caliper and one of the cases that I loaded and fired in the rifle. I guess the cases may have sprung back .001 of an inch, but doubt it sprung back more. I checked all of the cases, both loaded and those that I had shot at the range that day and they all measure the same.
At this point I think the best thing would be to turn the cases down another .003 or .004 and start again. I’m open to suggestions, though.

Scott Y
View attachment 1265668

I wish that when a gunsmith chambers a barrel they should stamp on the barrel the reamer neck diameter and the free bore. I have a well known gunsmith do my work and they put no details on the barrel or on the receipt.

 

[divingin]

Replies have pretty much addressed your problem, so I'll just throw out that both my buddy and I have found that 5 thou off the lands seems to be the best for us using the Column bullets.

Do you have any way to mechanically expand the case neck (a turning mandrel, for instance)? If you can expand it large enough that it doesn't easily chamber (you can do part of the neck), lube it up and force it in, it should end up a thou or so over the chamber neck diameter. Should get you a spitball number.

 

[newbieshooter]

I wish that when a gunsmith chambers a barrel they should stamp on the barrel the reamer neck diameter and the free bore. I have a well known gunsmith do my work and they put no details on the barrel or on the receipt.

My local smith usually engraves cartridge and neck. I ask him to add additional info:
cartridge: 6BRAI
neck: .272
freebore: .135
rifle: LRBAT = LRB stock with BAT B Action
barrel: K#5 = Krieger #5

 

[Webster]

My local smith usually stamps cartridge and neck. I ask him to stamp additional info:
cartridge: 6BRAI
neck: .272
freebore: .135
rifle: LRBAT = LRB stock with BAT Action
barrel: K#5 = Krieger #5
View attachment 1266901

Kelbly is now laser engraving data on barrels. I always wondered if stamping altered the barrel internaly.