6.5 x 47 c.o.a.l with 123 scenars .170 reamer.

[.300wsm]

I am having early pressure signs with my 6.5 x 47 lapua. Just did the alex wheeler method today to measure to the lands. Buy using my old method with the hornady tool i was jamming quite a bit. Maybe the reason for early pressure signs..

My action is a atlas tactial and the reamer that was used was .170 freebore with a .294 neck. My coal is 2.690 just touching the lands. 2.143 cbto. Does this number jive with a .170 freebore reamer??? Seems to be shorter then normal.

Thanks for your responses...

 

[ShootDots]

I have a .167 freebore (I call it .170 because it is so close) BUT I also have about 1000 rounds down the bore. The 123 Scenars, using the "Stonypoint / Hornady" tool method, not the "Alex Wheeler" method, which is going to be a bit more accurate, is "just touching lands" at ogive is 2.134. So you are right in the same ballpark. I would like to know what your load is. Mine is 38.0grs of Varget and the bullet, using the Hornady method, is seated at 2.131, just barely off the lands. No pressure, excellent accuracy.

 

[.300wsm]

I settled on 36.8 varget with the 123. But at 37.2 i would get ejecter marks and a swipe.
I see others running much more and no problems. Then i saw the thread about how to measure to the lands by alex wheeler and found i was jammimg my rounds about 30 thoudandths.
Maybe i was pushing to hard with the hornady tool.
Which explains my early pressure signs. I will load up some new rounds with the right distance to the lands and see what i get.

 

[ShootDots]

I settled on 36.8 varget with the 123. But at 37.2 i would get ejecter marks and a swipe.
I see others running much more and no problems. Then i saw the thread about how to measure to the lands by alex wheeler and found i was jammimg my rounds about 30 thoudandths.
Maybe i was pushing to hard with the hornady tool.
Which explains my early pressure signs. I will load up some new rounds with the right distance to the lands and see what i get.

Jamming them definitely raises pressure. That could well be your problem. I also have a question: "how much neck clearance is there in your chamber?" You should have at least 3 thousandths and 4 is even better.

 

[.300wsm]

The reamer was .294 no turn neck. A loaded round measures around .290 should be good on neck clearance.

 

[mikegaiz]

I would jump them at least .008 to start with. Most Scenars shoot best from .005 to .015 jump.

 

[ShootDots]

I just had another thought.. How far are you bumping your shoulders back? I bump mine at least 2 thousandths and 3 thousandths, in my opinion, is better yet..

 

[.300wsm]

I bump shoulder 2 thousandths. I will try jumping around 5 thousandths and play around from there. Now that i actually know
Where my lands measurement is.
Thanks for your replys so far. Hopefully get to the range sometime next week.