Re: Need advice on barrel
the 6br, you need to define more exactly what the use is.
If a short range (100-300 yards) pure BR gun, then skip the 6BR and go 6PPC with 1-14 because bullets are always under 70 grain. Pure top competition accuracy cartridge for 300m and under. Nothing beats it.
If not short range Br but use out to 600 yd, then go with the 6BR. If you plan on shooting up to 85 gr bullets, go with 1-12, 85-95 gr go with 1-10, 95-107 gr then 1-8 twist. guys with improved versions of the 6Br are pushing 107s in 1-8 twists out to 3000 fps with 28-30" barrels out to 1000 yards. The 1-8s also will shoot the 95 Berger VLD very accurately in the improved case out to 1000m.
In the improved BR, look at the BRX and the BRS (Baby Shehane). I would go with the BRX for ease of making brass. Go to longrangetargetshooting.com or Benchrestcentral.com and ask about the BRX, Bob Crone will give you all the info you want. Do a search and will find much info already posted. Bill Shehane is advertiser on Brcentral. Look under D B supply.
For barrels, the top ones are the 3 groove Lilja, the Hart with ratchet rifling, the Spencer, the Pac Nor, Krieger, K & P, are all top notch barrels and cannot go wrong with any of them.