Hope this is the correct forum â€“ first time posting. Mostly I have been a Bullseye Pistol/Skeet Shooter for years and have mainly collected rifles rather than shoot them. Since moving to an area that provides more opportunity for rifle use (i.e., hunting and competition) my interest in long gun shooting has increased. During one cold morning while reading one of my reloading magazines I came across a comment that any of the â€˜06â€™ family can be re barreled to the 240 Weatherby, 240 Gibbs, or 240 Hawk without having to extensively modify the bolt or magazine. The Hawk as I understand is based on the 280 case but can be formed from a 30-06 case. Further reading lead to several articles that the 6mm Norma BR is another option because of it being extremely accurate and provides extended barrel life (which is a consideration of mine), however, it is based on the 308 case which is a short action cartridge. I believe the bolt on the 30-06 would work with a 308 case since it is a shorter 30-06 case. I would assume this would require more work in making sure the bolt locks are locked in place correctly and the head space between the bolt and barrel and cartridge is correct. Currently I am in the early stages of project planning to convert an older Remington 700 BDL (which was originally configured in 30-06 caliber) custom built to a 240/6mm cartridge. The primary use of this particular configuration is varmint, coyote and some local competitions (300 to 600 yards) preferring to use a 25-06 for larger game (e.g., deer, etc.). What cartridge would be appropriate to build the custom rifle? Would building a 6mm BR just be adding extensive cost for retooling the bolt and magazine, etc.? While commercially available brass is a preference I do reload ammunition and would not mind forming brass if it is not commercially available.