6xc "bolt click"

[SurgeonCO]

I've been shooting the xc for a couple of years and really like it. I have come to the conclusion I do not like the Norma brass. I bought some Lapua 6.5 Creedmore brass resized to 6xc. Doing a bit of load development today with H4350 and 115 DTAC. From 38-41 grains did not have an SD over 8(5 shot groups). 40.5 Grains was 3012fps avg SD of 3, .2moa. From lowest to highest I had the "bolt click" at primary extraction. No pressure signs at all throughout. So now I've been looking at the 6xcII print to make sense of it. Looks like the base on the 6xcII is slightly bigger than my regular 6xc reamer. Does anyone have input on this? Thanks in advance

 

[kolar55]

I've been shooting the xc for a couple of years and really like it. I have come to the conclusion I do not like the Norma brass. I bought some Lapua 6.5 Creedmore brass resized to 6xc. Doing a bit of load development today with H4350 and 115 DTAC. From 38-41 grains did not have an SD over 8(5 shot groups). 40.5 Grains was 3012fps avg SD of 3, .2moa. From lowest to highest I had the "bolt click" at primary extraction. No pressure signs at all throughout. So now I've been looking at the 6xcII print to make sense of it. Looks like the base on the 6xcII is slightly bigger than my regular 6xc reamer. Does anyone have input on this? Thanks in advance

I recently had a 6xc built and use Norma brass. I don't seem to have the bolt click problem and have pushed some of these to an ejector mark on the case head. However, I had a full lenght bushing die made from the reamer print by Whidden. So far no problems and they size smooth and consistently easy. Might be worth a look. There are others that have a lot more experience with the 6xc and it's bolt click problems and can probably shed more light on the subject. I have shot some amazingly small groups with this thing with 95 Berger HVLD's and Sierra 70 Blitzking bullets. Very happy with the rig for a hunting rifle that doubles as deer/coyote gun.

 

[Dave Marshall]

The problem you're having is in the neck thickness of the 6.5 creedmoor brass. When you size it down to 6xc, the neck becomes what used to be part of the creedmoor's body. The brass is too thick at the base of the new 6xc neck.

Friends of mine with looser neck tolerances than my chamber report that the bolt click only occurs on the first firing of the creedmoor brass. After annealing and sizing, the second firing should be better. My chamber was too tight and I gave up on the project. Norma brass is great as long as you don't push it too hard. If you need more speed, try RL16.

 

[SurgeonCO]

The necks have all been turned. I’m going to polish the chamber and see if it helps. I shot this brass from 38-41 grains of h4350 and the highest as was 8, lowest 3. I will check the necks. They were bushing sized after the first firing and seating force was very consistent

 

[riflewoman]

The base of the cartridge is too big for your chamber. http://www.6mmbr.com/CarstensenJLC01.html

See just above “A full custom die”. For an explanation.

This is the main reason I never liked the XC. Or the X. I chambered a 6-250 an just lived with the body taper, easier that way.

 

[dkhunt14]

Most of the time bolt click is from the back of the case. It needs sized more then the die can do. Usually the problem occurs when tight at the. 200 line reamer are used. Most times it can be stopped with A die that sizes more. Matt

 

[SurgeonCO]

My rudimentary polishing helped a bit. I talked to my smith and he’s going to go note in depth with the polishing. Will update when I get it squared away

 

[tuttlefarm]

Has anybody checked the bolt extraction timing, seen alot of bad timing on case
extraction

 

[tclaunch]

You should visit 6mmar.com site and compare reamer drawings of the 6XC and 6XCII. The problem is the .200" line diameter causing the click at the top of extraction. The Norma brass is based off the 308 diameter and the 22/250 is smaller. If you plan to use Norma brass, then you need the XCII reamer OR purchase custom dies. Robert Whitley also sells a Redding S-Type FL die made for the XCII. I chambered 2 barrels with my reamer in XCII for a buddy and nary a hiccup.