It takes a lot of courage to start a new rifle manufacturing company these days, especially one that is trying to build a semi-custom rifle at a popular price point. Good luck on that.
I build my own rifles on Savage Precision Target Actions, Remington 700 and now 783 actions. While primarily I build for varmint hunting, I also just like to experiment. One thing I have learned from actual shooting tests of various barrel twist rates, is that faster is better across the board. Not only that, all one needs to do is measure the length of a given bullet and plug the data into a twist calculator to obtain the desired twist. Here are two twist calculators and one ballistic calculator:
http://www.jbmballistics.com/cgi-bin/jbmstab-5.1.cgihttp://www.bergerbullets.com/twist-rate-calculator/http://appliedballisticsllc.com/ballistics/As for .243" (6mm) bullets, what I discovered is that all the old ideas are completely wrong in light of the new monolithic copper expanding bullets and the compressed copper/tin compressed core jacketed frangible bullets. For example the 62 grain Barnes Varmint Grenade when fired in a 6mm PPC with a "standard" 1:14" twist would only occasionally hit a 100 yard target, and when they did they were completely sideways. So, without using a twist calculator, I followed the bullet manufacturer's recommendation of a 1:10" twist and ordered a corresponding Shilen barrel. That twist stabilized the bullet, but groups were still running around 1.5" or larger.
So I plugged the bullet data into a calculator and found the 1:10" twist was marginal for stabilizing that long (0.974") and light weight (62 grain) bullet. The calculator revealed that a 1:8" twist would stabilize the bullet at all velocities. A new 1:8" twist barrel chambered for the .243 WSSM shot ten round groups between 0.185" and 0.300" depending on conditions. I want the resulting Stability Factor to be at least 1.5 and closer to 2.0 if possible, in this case the 62 grain Varmint Grenade at 3,580 fps returned a Stability factor of 1.898, good to go.
This also proved true for the .224" regardless of cartridge. 1:10" Twist did not provide the degree of accuracy I was looking for in the .22-250 Remington with the 50 grain Barnes Varmint Grenade, but a 1"9" twist worked across all cartridges from the aforementioned .22-250 Remington, its Ackley Improved version, and the .223 Remington. It also stabilized the lighter Nosler 40 grain BT Lead Free and the Nosler 69 grain Custom Competition Bullet, as well as any other I worked up loads for.
So now my standard .243" twist is 1:8". And I use the 1:9" twist for all .224" applications, except a 1:8" twist for AR-15's with heavy bullets. I currently have two 1:8" twist barrels in the works for the 6mm PPC (Brux) and 6mm BR Norma (Kreiger), which should prove the application from the little PPC to the larger .243 WSSM.
It was also discovered that the 1:12" factory twist for .204 Ruger was just too slow. It was the reason that some had poor performance with 39 grain plus bullets. I began testing with a 1:8.5" twist especially for Berger's 50 grain HPBT .204 bullet. While the bullet shot consistently in the 0.5" range for ten shots, Berger discontinued it in favor of the 55 grain HPBT bullet. Still, that 1:8.5" twist kept the groups under 1" and with a bit of load tweaking would have probably done better.
That 1:8.5" twist also shot the 26 grain Varmint Grenade in the .25" class, and at 4,110 fps. I had a Hart barrel made for an AR-15 build with a heavy contour 1:9" twist barrel, that shoots Hornady's 24 grain .204 NTX BT bullet at 3,900 fps well under .5". It also handles every various brand conventional bullet similarly. So that now my standard twist for the .204 Ruger is 1:9".
So far all the supposed drawbacks of fast twists imagined by the pundits, bullets coming apart from too much spin, excessive spin drift, etc., have not shown up. So I recommend if we are to err in selecting a twist rate, err on the side of faster rather than slower - because nothing will make a twist that is too slow work optimally.
