I shoot zero freebore, up to my own 75g
VLD on a .900 jacket, fantastic accuracy in the 6 BR.
60g Sierra with H335, 322, and LT 32 will SHOCK you, and so will the 55g nosler.
Gene Harwood, NBRSA Director at one time sat a world record with his 6 BR, zero freebore, shooting his own 60g Bullets with H335 at 3700 fps out of a Max Heavy Varmint rig in a registered match. Gene chewed me out when he saw that I was shooting H322 in my 6 BR with 60's...he proved dead right on my next trip to the range...shot some very, very small groups.
I made a 60g flat base on a .750 jacket with a .070 meplat that had very little bearing surface, jammed .030 shot extremely small groups. Then a 62g BT bullet on a .825 jacket .070 meplat, jammed that shot lights out also. H335 will shoot groups so small it is shocking, but you have to stand on the load to get to the top end accuracy node. Few if any will believe it, but I laid it out for you.
My bullets had a .2433 shank and a .2435 pressure ring, similar to some lots of Euber and Bib bullets that I have purchased. When you find a barrel that likes an oversize bullet, they usually will shoot "hummer" type groups.
Barrel life in a 6BR is unbelievable with H335, we hammered used, re-chambered benchrest barrels on p. dog towns trying to burn them out, cleaning only 300-450 shots, took 8000-10,000 rounds for them to quit shooting in the high 2,s- 3's. We foudn that we did not get this kind of barrel life with H322 or AA 2015. We would always shoot till we could not see out of the scope, then go to another one, repeat. 6 BR and 6 PPC on a hot dog town is a wicked lawnmower, especially if you are shooting a RBLP where you can accurately shoot 5-6 rounds a minute. We learned on a fiberglass stock, SS barrel, Panda actions, fill the barrel channel full of 50/50 water and rubbing alcohol and just keep shooting. A 6 BR and 6 PPC barrels are just hard to kill while shooting H335. I made 22 and 6 ppc brass from PMC 7.62x39 brass, brass is tough as nails while imi, fed, rem, and win is junk for forming into the PPC case. Groups in the low 2's is the norm for PMC formed brass in both PPC's with the large rifle primer, and I would not recommend the PPC case forming process unless you have some real tough 7.62x39 brass. PP brass may be good, and infrequently, guys can find once fired Lapua 7.62x39 brass.
I am a firm believer in a zero freebore reamer, also have throater, and a .060 reamer. I feel like I am throwing away barrel life with the .060 reamer as it takes 3000 rounds+ to wear a 6 BR barrel .060 with H335 with light bullets.
H335 has the characteristic in a 14 and 12 twist barrel to shoot better the hotter the load with 55-65g bullets, right up till you can't get the bolt open in most barrels. So, most are screaming about temp sensitive powders. So, don't pre load 335 to the top end of the powder charge, and DO NOT leave your ammo out in the SUN! We worked up our loads in 68*-75* temps, then went to S.D. and shot p. dogs in the Summer, 90-100* temps, for 12 years straight, multiple trips a year. We used Rem 7 1/2 primers, and had the firing pins bushed if they needed it. I did see pressure spikes with a used 8 Twist 6 ppc with a .060 throat shooting 60g Sierra's at 3550 in a 6 ppc with H335. I gave that barrel away after one trip where I put 1000 rounds down the tube.
