Tony (Login tonyk1960) Posted Dec 31, 2016 3:13 PM
Interesting discussion once again, it seems that there are as many different reasons to try as many different twist rates as the dollars would allow. Is there an optimum twist rate? I had a copy of "Hatchers notebook" a number of years ago (lent and never returned) but in there he talks a lot about stability in flight, and gives a formula to work out the optimum length of projectile for a specific twist rate. Not being a physicist but I am sure if I had that formula in front of me I reckon I could work out the twist rate required to stabilise a specific length of projectile. Now that's a project for my spare time.
I have heard from a lot of people that they couldn't get their STI's to shoot, unfortunately over in Aus it's a little difficult to send it back to the factory, that is why we have so many aftermarket barrels available, and no-one I have spoken to has been able to find the manufacturer of the barrels either.
I think we are all aware that the original PPC round was a 148HBWC and it was the foundation of many a great score, and still is. Finding a good manufacturer these days is hard, but they are there and we keep them going strong. With the decline in this style of target shooting (PPC and ISSF) and the rising of IPSC and Action pistol where "fast is best" has lead to a new breed of projectile coming out and the manufacturers catering for that is causing the shortage we all feel. I won't get on the soapbox about powders and primers either.
So optimum twist rate for PPC, does yours work? If it shoots good groups that you are happy with then it's the right twist. If someone gave me a barrel with a 1:50 twist, I have a spare gun to try it on, but wouldn't just go out and buy a barrel because it's there and available. My 1:8 shoots fine, I've shot everything from 100SWC's through 148HBWC's to 160 HBWC's for our Service Pistol match to make power factor, even shot Action with them with some success.
Ultimately, it's the nut on the butt. There is no substitute for skill.
Happy New Year to you all and looking forward to some great discussions this year