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6xc twist for 105 and 115

I am thinking around 3000 to 3050 on speed with the 105's. From most of the stuff I have found pretty close to what slayinswede is looking at.
Swede what barrel exactly are you running? What are your conditions? Elevation and such
 
4 6xc here all in 8 twist. 105and 115 dtacks. The berger barrel twist calculator shows the 115 dtaks are stabilized. 8 twist is all i need. I’m at 6000 ft elevation. Sea level you need a 7 twist
Unless you never shoot below 1000 ft you could use a 7.5 twist.
And of course the air temp is a factor
 
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CLance said:
I am close to sea level
Click to expand...

So am I. When I started shooting the DTAC back in '07 I lived in Palm Beach County, Florida, now I'm in N. Florida.
My experience has been excellent stability and accuracy to the target over 1000 yards in a 7.5 twist. If it makes you feel better with peace of mind get a 7 twist. It will run 105-115's. I would shoot a 7 twist if I thought I had too, but I have confidence and experience in the 7.5 doing the job all the way to the target, and not leaving anything on the table in the way of accuracy.

Don Dunlap
 
150 to 300 feet above sea level is norm. Temps low for me to shoot would be say 50. Berger says 1.4 plus with 105 hybrid and dtac and a 8 twist. High 1.89 with 105 and hot temps around 90 and a 7 twist barrel.From what I can find my bullet rpms would be about 315,000 with the 105's. I can get the 7 twist or the 8 twist right now but would have to wait on a 7.5 twist.
I cannot find any info on how much twist is to much per SG number.
 
CLance said:
150 to 300 feet above sea level is norm. Temps low for me to shoot would be say 50. Berger says 1.4 plus with 105 hybrid and dtac and a 8 twist. High 1.89 with 105 and hot temps around 90 and a 7 twist barrel.From what I can find my bullet rpms would be about 315,000 with the 105's. I can get the 7 twist or the 8 twist right now but would have to wait on a 7.5 twist.
I cannot find any info on how much twist is to much per SG number.
Click to expand...


Since the 7 is available, get it.
 
Nope not planning on going crazy. Want accuracy. From what I have seen 105's should run 3000 or just above.
 
I went past 3,250 fps testing propellants in a 1:7.8 30" Bartlein barrel with 105VLD's late in 2008.

Rifle built by Carl Bernosky on a Quadlite action late in 2007, chambered with Henriksen's 7/03-dated reamer profile. Norma LRP brass, RL17 propellant, KVB7 primers, 75°F @ ~ 800 ft. Same day with 8208XBR a bit over 3,200 fps.

Vertical at 600 yards was 2" with the 8208XBR, 6" with the RL17. Brass was toast.

I have some Peterson and Alpha SRP brass, haven't shot it yet... might make all the difference. I know SRP is a big plus with Palma loads for 308WIN, why I bothered making 6XC cases from Lapua's Palma brass after all my experiences with 6XC LRP were disappointing. Those Lapua cases lasted three or four times as many reloadings as any Tubb-stamped or Norma LRP 6XC brass ever did.

You were shooting Tubb's hBN-coated RBT115's at Canadian?
 
Just heard back from John Whidden. He’s always used 1:8 barrels for his 243’s, says one 1:7.5 shoots “just as good” with moly’d Berger 105 Hybrids.

Speed?

3,265 fps!
 
Just ordered the 7 twist. I hope to be Iok since I am close to sea level and usually have a lot of humidity. I am not planning on hot rodding it either I will keep the speeds down around 3,000 + or - 50. I will update the thread once it arrives and I try it out
 
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spclark said:
I went past 3,250 fps testing propellants in a 1:7.8 30" Bartlein barrel with 105VLD's late in 2008.

Rifle built by Carl Bernosky on a Quadlite action late in 2007, chambered with Henriksen's 7/03-dated reamer profile. Norma LRP brass, RL17 propellant, KVB7 primers, 75°F @ ~ 800 ft. Same day with 8208XBR a bit over 3,200 fps.

Vertical at 600 yards was 2" with the 8208XBR, 6" with the RL17. Brass was toast.

I have some Peterson and Alpha SRP brass, haven't shot it yet... might make all the difference. I know SRP is a big plus with Palma loads for 308WIN, why I bothered making 6XC cases from Lapua's Palma brass after all my experiences with 6XC LRP were disappointing. Those Lapua cases lasted three or four times as many reloadings as any Tubb-stamped or Norma LRP 6XC brass ever did.

You were shooting Tubb's hBN-coated RBT115's at Canadian?
Click to expand...

Yes. New brass and coated bullets, h4350 made on his ammo machine.

Hey, no one was more shocked than me. His barrel is like 32 inches.
 
CLance said:
That would be what I would do also but it doesn't fit my timeframe. I can get either a 7 or 8 that are ready to go. Just not sure if the 7 is to much for the 105's . Has anyone had any experience with this combo and how did it work.
Click to expand...
I run 7 twist for both in my 6X47Lapua 40 degree. I swear the 7 twist is better for 103-105!
 
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