Hello all,
I hoping others can help me with a problem I'm having with the Cabela's special. I have read a few other threads here and really hope it is not a problem that it appears to be. I did not what to hijack another thread so I assumed starting a new one would be in order.
The short version: ogive of multiple brands/designs bullets 'jamming' on what appears to be the throat or lead on new firearm.
History: New M12 .223 with <50 shots fired. Both factory and handloads-
Winchester factory 55 grn SP flat bottom
PPU Match Line 68 grn BT/HP
These were the first shots during break-in and wanted a few pieces of Win brass for later testing. I was getting on paper at the beginning so I start at 50 yds. All 5 shot groups were .550 or less. No pressure signs as I always look at my brass carefully while a barrel cools. All is good at this point and expected to see about MOA or better for the first groups.

PPU The fourth shot rang horribly. Gas coming from areas where I have never experienced. I always wear eye and ear protection so here was the big pay off. Stopped. Checked brass and yep, bulging primers and the last shot biscuit pierced the primer. Wha tha?
Checked ogive variation with remaining rounds (Hornady OAL gauge), all seems good. Measured both fired and unfired brass lengths to be 100% sure these were not 5.56 spec. cases. Actually measured less than SAMMI slightly. Brass is stamped only 'REM .223' as well. Chalked it up to manufacture charges or primer quality.
I decided to hand load a few of my own knowing I am looking at everything to be certain. BUT I ASSUME (oh brother) that all is reamed or cut within SAMMI and I start out super conservative on my loads.
Hand loads were :
Winny brass 1.750
Neck size only .002
Varget: 22.8 grn (always weigh every charge..twice)
Hornady 55 grn SP
Chamfered and deburred
Seat depth: 2.200 = 1.839 Ogive +/-
CCI SRM 400

I still run cases through the firearm prior to charge to ensure all feels 'right' after sizing. I know, over zealous.
They feel just like they should.
Charged, loaded and run a few more seated rounds through the bolt. No resistance, operates smooth.
Groups all shot as expected, < MOA with fliers with this low charge. Two points of impact. I chalk this up to low charge and seating depth being at Hornady recommended. No signs of pressure.
At this point I want to know where exactly MY lands are as I start heading up the charge ladder.
Wha tha?
2.162???? As an OAL?? This is with my Hornady gauge. Measured again, and again, 20+ times and my readings are inconsistent and all over the place.
from 2.162-2.242. And with a fresh new bullet. Checked my modified case, including shoulder position. Perfect match to my chamber using both LE Wilson and Hornady Comparator.
Cleaned, scrubbed the throat lead area. It helped some but very little.
Paint a few bullets with sharpie, and look closely. A ring. A solid ring engaging the bullet a the ogive. Not completely around the bullet, but most of it. Did this no less than 10 times. Same result. More pressure on the bullet did not help. It will NOT touch the lands. I tried a 68 grn BT HP. Much longer and design. Jams at 2.247 with inconsistent results as well. It doesn't seem even close to the lands. I still haven't the lands yet.
I have measured and tried several other methods and though the results are somewhat different in the exact distance to this interference, the short distance remains and the bullet is striking what feels like a solid wall.
I measured the bullets and they are 223.5 +/- .0005.
I found what seemed to be a clue, Of the countless attempts to measure, once or twice i felt the bullet pass by that wall and slip to a deeper depth. About .080 deeper. But only with the 68 grn bullet. And a slight ghost of lands on the bullet but not at the ogive, But well before the ogive closer to the tip.
Am I missing something? Could this throat, lead or freebore be reamed canted of undersized?

Sorry for the length, I wanted to include as much as possible.

miocene