Today, I shot a friend's 6.5x47 Lapua. The rifle weighs 14.4 lbs. The recoil surprised me. It was not as bad as expected. I really expected worse. The rifle was shooting 123 Scenars. I was in a T-shirt, so no padding on the shoulder of any sort. While I said earlier I would opt for a muzzle brake, I am leaning the other way now. The 6.5 had more of a firm push to it than the next rifle I shot, a 243 Winchester in a Ruger Precision Rifle (RPR). That rifle was a round one lb. lighter than the 6.5. The 243 was definitely less pleasant to shoot, hitting my shoulder harder I think, but with a notably quicker "hit". The owner said velocity was 3300fps. Not sure that is hot or not, but just mention it here since I had the info.
Since many consider the 243 as having minimal recoil, not sure what to think. Maybe the stock and butt pad on the 6.5 really helped. The stock on the 6.5 was a Stockade "Pairie Dog Special/Tactical" housing a Savage single shot target action and heavy varmint barrel.
The range had a back wall and roof, with side walls at each extreme end. Maybe 12 stations total. Someone was shooting a rifle with a brake. Very obvious. Loud and the concussion was felt. Really didn't care for that, and I was using my best ear plugs under some bulky Peltor ear muffs. That controlled the sound reasonably well, but concussion obviously remained.
Seems to me a heavyish rifle with lighter bullets in 6.5 in a good stock chassis, w/o muzzle brake may work. Plan is to use a XLR Element chassis.
Phil