The 122 doesn't like the jump that comes from factory throated 6.5's that have rounds down them.
When I did prototype testing it was a SAAMI chamber but it was brand new, 20rds of box ammo and then right to the flatlines.
I didn't have any problems but then again it was a really good match barrel not a mass produced, who knows what the throat/twist/bore dimensions are barrel.
The problems that we've seen have almost universally come from things like RPR's, Tikka CTR's, Savage factory barrels.
There are a few things going on but the looooong throats traditionally cut into factory barrels are not a friend of the 6.5
Other things are ahppening too, I got my hands on an RPR OEM barrel that shot factory ammo well (appx 3/4") and the flatlines were shotgunning and fouling like crazy. Slugged the barrel and found out it was nearly 1.5 thou oversize. Heavy jacketed bullets obturated into the bore and had a lot less fouling and sealed up well. Not so with the 122's. The barrel twist was closer to 8.5 than 8 on the CTR that gave a local guy fits.
About 2 years ago I had a guy call me an cuss me sideways for the 198 not shooting in his 300 Norma.
His jump to the lands was 360 thou, almost 1.2 bullet diameters. Yet because the bullets were expensive they were supposed to magically deal with a jump that long. When I asked "what do you jump those 230's at?"
18 thousandths...
So 20x more jump with the 198s and it was a bad bullet design.
As soon as his buddy, a customer of mine, put them in a 300WSM he fired 6 rounds.
3@100 clover leaf
3@ 1,000 were sub 4"
