Help with loads 6mm dasher

[essexboy]

Hi all, hope you guys can help,
I've just started fire forming my cases using 31grains of vhit 540 105 grain a-max and all seems to be going ok [ lost 1 split neck].
The bullet i'm going to be using is the 105grain lapua with n540 or n550 primers are cci450, do you think starting at 31grains and going up will be ok or start a bit lower, i will seat the bullets 10thou back from the lands.
The barrel is a 1-8 twist .236 land bartlein 28", action is a tikka 590 [ not sure if that helps or not]

 

[Erik Cortina]

Hi all, hope you guys can help,
I've just started fire forming my cases using 31grains of vhit 540 105 grain a-max and all seems to be going ok [ lost 1 split neck].
The bullet i'm going to be using is the 105grain lapua with n540 or n550 primers are cci450, do you think starting at 31grains and going up will be ok or start a bit lower, i will seat the bullets 10thou back from the lands.
The barrel is a 1-8 twist .236 land bartlein 28", action is a tikka 590 [ not sure if that helps or not]

31 gr. is a good place to start with N540. With N550 I would start around 33 and work up from there.

You should find an accuracy node with N540 at around 32.5 gr. @ 2960 fps. with 96.5% case fill ratio.

With the N550 you should find the node around 35.0 gr. @ 3040 fps. with 102.8% case fill ratio.

Good luck, let us know how it shoots!

 

[TonyR]

Can you fireform for a Dasher without creating a false shoulder in some way? As I read the post, the bullets are not even jammed. I have heard all sorts of stories about fireforming wit too much headspace.

 

[Erik Cortina]

Can you fireform for a Dasher without creating a false shoulder in some way? As I read the post, the bullets are not even jammed. I have heard all sorts of stories about fireforming wit too much headspace.

Tony, he said he fireformed using 105 Amax, but he does not tell us the relation of the Amax to the lands, I would imagine they are jammed. He talks about jumping the Scenars, I believe he is loading the Scenars in fireformed brass.

 

[essexboy]

Sorry for the lack of info, yes i'm fire forming using the false shoulder method with the a-max, the loads for the lapua are all formed, i'm off to the range on friday so will report back, many thanks for the replies, i will try as suggested.

Steve

 

[essexboy]

Range report,
The fire forming loads were printing .500 groups with a best of .452 @ 2845fps, then the chrono packed up, but i now know that i can shoot f class type comps and not be to bad off [ why waste barrel life]
I went with the n550 as suggested but only had limited time, results as follows
n550 33g -10 off lands 105g lapua .627 group
n550 33.5g -10 off lands 105g lapua .359 group
n550 34g -10 off lands 105g lapua .727 group
n550 34.5g -10 off lands 105g lapua .107 group

The next time i'm shooting is a Mcqueens sniper comp at 200yards in 2 weeks time with a static zero target i will load up some more in .2 steps from 34.4 and report back.


Regards

Steve