Caiati,I am thinking about starting a somewhat unorthodox build and need help from the experts out there. I'm currently hunting with a 6.5PRC which I love. I've have been shooting/hunting suppressed on/off with it and the only thing I don't like is the length of the barrel and suppressor together which on my current rifle is 31".
I've got an idea to build on a hot rod cartridge but cut the barrel down to 19 or 20 inches which will give me the barrel length I want but also slow my cartridge down as to not burn my barrel out so quickly. The key for me is to pick a cartridge either in the 6.5mm or 7mm family that usually screams with a standard 24 or 26 inch barrel and by cutting it down still achieves the same or better numbers than I'm getting with the PRC. If I would cut the PRC down, I would have less energy and speed than a 6.5CM which isn't what I want. The big deal is I need to pick a caliber that will still have efficient powder burn with a shorter barrel. I'm thinking one of the short mags is going to get the nod, but I'm not completely sure. Any suggestions on caliber?
I run a lot of barrels from 15-18 inches.
Barrel length, whether 24-26 or 18-20 inches is not going cause your barrel life (throat life) to be any different.
Take the whole idea of efficiency out of the equation too.
Decide what MV you want with a specific bullet weight and go from there.
On average you are going to lose around 30 fps per inch of barrel
I run all kinds of big cartridges in 17-18 inch barrels: 25 PRC, 6.5-284, 6.5 PRC, 6.5 WSM, 26 Nosler, 284 Winchester, 7mm SAUM, 7mm WSM, 7mm LRM, 7mm Remington Mag Improved, 7mm Dakota, 300 RUM, 338 Lapua Improved (338AX).
I get great accuracy in these 17-18 barrels, so you don't have to worry about 19-20 inch barrels