6BR- Ackley Improved 40 degree

[Terry Altom]

Just run the BR AI reamer in should do it I would think

I wonder about running a Dasher reamer in?

 

[JamesnTN]

I wonder about running a Dasher reamer in?

You'll need to leave a crush fit for the BR go gauge of .001-.002

 

[johara1]

I wonder about running a Dasher reamer in?

Terry i would guess depending on the rounds shot in the barrel i would set it back the length of the neck. It would be better to cut the threads off and chamber it. It would dependent on the round count...... jim

 

[Terry Altom]

I have a 6brAI, 6BRDX and a dasher. I like the 6BRAI at 31.8 Varget, shoots very well from 30.9 to 32.2 gr. My DX shoots extremely well from 32.2 to 32.8 gr Varget. My dasher will only shoot when it feels like it. Even tried giving it some Midol!

Would you mind defining "very well" and "extremely well"?

I'll put myself out there first. I can get some decent groups like these, just not consistent enough to be competitive. My awesome groups one day turn into just OK the next time out. These are from my new barrel. My old barrel on a Remington had a .050 and .086 MOA, but again, not consistent.


Minute of Angle
-------------------------------------
MOA___C - C___Horiz___Vert
0.125__0.052__0.052__0.123
0.150__0.059__0.143__0.112
0.180__0.082__0.104__0.176
0.193__0.080__0.159__0.121
0.216__0.086__0.208__0.082
0.273__0.125__0.264__0.175
0.303__0.125__0.301__0.212

 

[JamesnTN]

Emphasis on GOOD cases. I think this is 99% of why most will shoot better with the Ackley. The other thing is the noticeably less erosion will help those that are less disciplined about staying on top of it.

Tom

Tom

Have you done an actual seating depth test on throats growth? I just checked mine when I got home from Memphis and I have found my throat ha moved forward .039 out of 550 rounds. That's roughly .007 per 100 rounds of shooting pretty mild loads. 2900-2920 fps.

 

[JamesnTN]

@JamesnTN

Dasher or br-Ackley?

I'm out of town for work, but have good notes at home on every barrel
Tom

BR AI

 

[LRPV]

BR AI

That's A LOT even for a Dasher. Use the same bullet when you checked?

 

[JamesnTN]

That's A LOT even for a Dasher. Use the same bullet when you checked?

Not the same exact bullet but yes the same bullet that I made

 

[LRPV]

Unfortunately I've also documented some of my best have been fast movers.

Tom

Truth^^^

 

[Terry Altom]

Tom

Have you done an actual seating depth test on throats growth? I just checked mine when I got home from Memphis and I have found my throat ha moved forward .039 out of 550 rounds. That's roughly .007 per 100 rounds of shooting pretty mild loads. 2900-2920 fps.

Ah now don't start scaring me.....I'm getting ready to have my Dasher reamer reground.

 

[JamesnTN]

Ah now don't start scaring me.....I'm getting ready to have my Dasher reamer reground.

I'm gonna check my LG barrel and see how much it's grown also and will publish results.

 

[Ga. Dawg]

I think it's best to use the same bullet each time, for what it's worth.

Mike

 

[JamesnTN]

I think it's best to use the same bullet each time, for what it's worth.

Mike

Probably so. But since it was made on my dies and same lot of jackets and cores. Measurements are close enough that it takes the optical comparator to actually measure any difference.

 

[Scarab]

Sharing: my BRAI throat has moved .009 in 160 rounds. Moved .006 in the first 75 rounds probably from barrel break in I guess.
My 30BR has moved .030 in 1800 rounds measured with the same lot of bullet.

 

[Terry Altom]

Sam Hall, I expect you've got quite a few rounds on more than one barrel. How about throat advancement measurments?

Of course we all understand max load versus mild load, fast powder versus slow powder, but some comparison is better than none.

 

[22DASHER]

Sam Hall, I expect you've got quite a few rounds on more than one barrel. How about throat advancement measurments?

@HUNTER3401

 

[JamesnTN]

Sharing: my BRAI throat has moved .009 in 160 rounds. Moved .006 in the first 75 rounds probably from barrel break in I guess.
My 30BR has moved .030 in 1800 rounds measured with the same lot of bullet.

That's .0056 per 100 rounds not far off of my .007 per 100

 

[JamesnTN]

James was that with Varget and your 104's at like 2960? Or something hotter?

105-103 grain bullets Varget and anywhere from 30.8-32 grains. Settled on 31.5 at 2920 fps never got over 2960 fps in this barrel.
100 rounds were fireformed at 30.2 grains of Varget.

 

[swd]

Since you guys have a little time on the BRAI now, how does it compare to the Dasher? Good and bad points.

 

[JamesnTN]

Since you guys have a little time on the BRAI now, how does it compare to the Dasher? Good and bad points.

I find it has a larger tune window on powder charge. Give it time and you'll see it winning matches.