I've had funny results with accuracy using the TSX in factory loads. Sometimes great, sometimes ho-hum..... never bloody awful, but enough dif between great and ho-hum to make me think it's the bullet, or the ammo as a whole. I've experienced sub-MOA to struggling to stay under 2" (all with 62's).

Be it known that I think very highly of Barnes. As I recently said in print (SWAT Magazine), they have been the most innovative in recent years, with the Varmint Grenade (found it extremely accurate in 6X45 loaded by both CorBon and Black Hills), the TSX and the TTSX. Barnes copper bullets to me are simply "the way to go" for most rifle and pistol applications that are of interest to me. Just maybe not match shooting. I mention this only to see what others have found.

Looking for causes, I bought some 62 grain TTSX's, thinking I will pull out all the stops and see what a carefully crafted handload might do with it. Haven't got there yet and I think I was fooling myself about the possibility of finding time for it, but in this box of 50 TTSX's, I found some things that don't seem conducive to great accuracy.

I noticed when CorBon first started loading the TSX in .223 that the grooves were a secondary operation. I always figured that even a thou or two of eccentricity on the grooves wouldb e a detriment to accuracy. I have not yet tested any for that. What I found sofar in this box of 62's though, is what looks like some inconsistencies caused by the tumbling process.Left to right, the pic below:

1. Driving bands full width, nearly
2. Bullet has been tumbled considerably more in whatever it is. Something like #7 shot, stainless I suppose. Band-to-groove transitions are very rounded.... band width for rifling engagement is considerably reduced.
3. Same as #2 but with burrs of copper left in grooves. Probably don't truly hurt but for sure they don't help. 2 and 3 have bodies and ogives mottled from tumbling.... not saying that's a problem. Maybe even some "golfball dimple" aerodynamic help. Maybe a good thing if they all had it.
4. Halfway between the two extremes, with burrs in grooves.

All out of the same box. Some of the bases are actually a tad peened over. RBS, my benchrest-legend pal, always said that really, only the base matters. They actually experimented with filing tips into all sorts of inconsistent shapes-- little effect compared to base imperfections.

The grooves look to me to be ground in.... that's interesting. I can see marks from chatter or from an out-of-round wheel. Not that I think it matters unless the whole groove is eccentric.