T2K in 6xc and 115 DTAC BN

[Hoverp]

I am having a real problem with getting the 115 BN coated DTAC's even close to the listed 38-39 grains of H4350. I can only safely (due to sticky bolt lift ) get 34-35 grains max. I have done an 20 shot test at 69 OAT. I load with the SSS dies and full size .003 shoulder setback, Wolf Primers, Norma new brass, neck tension is .002 and the 115's loaded to just kiss the lands(ive tried set off and further into as well) at 34 grains Im fine no bolt lift problems, at35 ok but close....36 out of the question for rapid fire ....I dont want any sticky bolt lift at all. The primer pockets are NOT loosening at all and case growth is .003 at the shoulder consistantly. I have not chronoed these yet but was very curious as to why Im only good with 34-35max??? The barrel is a stock schneider 26 inch from Tubb. Its clean and the chamber is clean as well. cases trimmed to 1.90 as well chamferred and deburred.... case and bullet runout is awesome at .001

any others having sticky bolt at these low charge weights?

 

[Mudcat-NC]

Re: T2K in 6xc and 115 DTAC BN

Classic issue with the combination you are using (well, except maybe the BN 115s). Your culprit is two things, the Norma brass and the Schneider bbl. Keep in mind that your rifle may or may not behave like someone else's rifle that worked up that load data. But, I have seen this issue repeatedly with T2ks and as such, you wont see me shooting a 6XC Schneider bbl or Norma brass in any 6xc bbl.

Change brass and bbl and I bet you start getting better velocities without the bolt stick.

John

 

[DRAM40A1]

Re: T2K in 6xc and 115 DTAC BN

Is your bolt sticking at the top, camming, of the bolt throw or all the way through the lift? Do you have ejector marks on the case head?

My current load is 40 grains in new unfired Norma cases, Wolf primers, and 115 HBN. And yes I have a Schneider barrel.

 

[Hoverp]

Re: T2K in 6xc and 115 DTAC BN

How many reloads are you able to get ? I can shoot 39 grains H4350 with the 115 BN but on the 3rd reload its bolt stick time. This goes for 38 and 37 and 36 grains as well, I can get numerous more from 34 grains...

 

[DRAM40A1]

Re: T2K in 6xc and 115 DTAC BN

I wore my first barrel out with the first 300 cases. They have 7-8 reloads on them, in fact I just loaded fifty to shoot tomorrow. I had to back down to 39.5 for the new barrel but still load at 40 for the new brass. I suspect I'll back those down after fireforming to the new chamber.

Are you getting resistence on closing or just after firing. Maybe you could bump them a little more and see how that goes. I'm bumping .005

 

[DRAM40A1]

Re: T2K in 6xc and 115 DTAC BN

Also, you are using the guage to measure set back, that came with the dies right??

 

[Hoverp]

Re: T2K in 6xc and 115 DTAC BN

Yes, the case guage and also a stoney point .375 datum OAL that measures the .375 line on the shoulder. I set back .003 but have done further.004 as well. SSS has offered to take a look at rhe rifle so I am sending it to them. Great company!!