6mm Creedmoor short throat? Help...

[Lougler]

I just built a 6 creed with a 0.109 freebore and tight neck chamber pre-fit, knowing that I would be limited to reloads and top end bullet weight of ~105gn. This is my first experience with the 6CM too.

So far I'm really struggling with the load development, 87Vmax, 87BTHP and 95VLD's all shoot terrible. The 75Vmax's shoot pretty well though which leads me to believe that the freebore is way too short. I've also done a lot of reading on this topic and i think I'm getting more confused then when I started...haha

All of my 6mm rifles love H4350 so that is what I'm using along with Peterson brass.

Does anyone run this tight of a freebore and had any luck with 85-105gn pills? Any feedback is much appreciated.

If it’s truly a right neck chamber, check your neck clearance. Ran into this on a similar cartridge. Everything chambered fine, but once the necks were turned, accuracy came around immediately.

 

[Lougler]

If it’s truly a right neck chamber, check your neck clearance. Ran into this on a similar cartridge. Everything chambered fine, but once the necks were turned, accuracy came around immediately.

Edit, TIGHT neck

 

[jaygorski]

Edit, TIGHT neck

What size neck does your chamber have? 273 on down would be too large.

https://imgur.com/PcjkzXm

 

[Lefty Trigger]

My 6CM is a 26" X-Caliber 1-8 twist with a .109 FB and I shoot 105gr Hornady HPBT's and Sierra 107gr MK's with RL-16 at 39.1gr with CCI200 large primers. Velocity is 2997 with ES of 19 and SD of 7.7 shoots 1 inch at 300 yards. Oh, they really like to jump too, .050 to .070 jump is the sweet spot. Also tried the Federal small primer brass and I never could get any decent numbers from it. The 6 Creedmoor does an awesome job if your not a velocity racer, mine really looses accuracy with any load above 3050fps.

 

[jaygorski]

My 6CM is a 26" X-Caliber 1-8 twist with a .109 FB and I shoot 105gr Hornady HPBT's and Sierra 107gr MK's with RL-16 at 39.1gr with CCI200 large primers. Velocity is 2997 with ES of 19 and SD of 7.7 shoots 1 inch at 300 yards. Oh, they really like to jump too, .050 to .070 jump is the sweet spot. Also tried the Federal small primer brass and I never could get any decent numbers from it. The 6 Creedmoor does an awesome job if your not a velocity racer, mine really looses accuracy with any load above 3050fps.

I ran the Hornady 105s I've got .002" off with 41.6grs H4350 with a .183fb, had it rechambered with a .136" a few years ago. Shot a .4" group with that load. at 300yds, still shoots good with new chamber.