Here's some info, it's not mine ,just found it on the web:
For The 6.5 mm Version (6.5 x 47 Lapua)
The loads and testing was done in a 6.5mm 1:8.5 twist Brux barrel. The barrel is 31.5" (long for sight radius only) but this author is of the opinion, based upon other information obtained, that velocities will be very similar with barrrels down to 28".
Chronograph Testing (October 7, 2006)
Some chrono testing was done with the 6.5 x 47 in a Remington 700 MAK Tube Gun. Here are the results, all with Reloader 15, all with BR-4 primers and all with non-moly bullets:
37gr RL15, Sierra 120, .015" jump - 2907 mean velocity, ES 28, SD 10
38gr RL15, Sierra 120, .015" jump - 2988 mean velocity, ES 26, SD 10
37gr RL15, Berger 130VLD, .010" in lands - 2878 mean velocity, ES 20, SD 9
38gr RL15, Berger 130VLD, .010" in lands - 2956 mean velocity, ES 16, SD 8 - There
was sticky bolt lift on two of the rounds, so this is max in the rifle at this loading
37gr RL15, Sierra 142, .010" in lands - 2803 mean velocity, ES 31, SD 13
38gr RL15, Sierra 142, .010" in lands - 2869 mean velocity, ES 7, SD 2 - - There
was sticky bolt lift on three of the rounds so this is max in the rifle at this loading
The 37 gr load with the 120 Sierras was exceptionally accurate in the rifle.
Chronograph Testing (October 10, 2006)
Some additional chrono results with the 6.5 x 47 Lapua, all with H4350, all with BR-4 primers, and all with non-moly bullets:
39 gr H4350, BR-4 Primer, Sierra 120, .015” jump (2.650” OAL), 2790 fps mean velocity, E 15, S 6
40 gr H4350, BR-4 Primer, Sierra 120, .015” jump (2.650” OAL) , 2870 fps mean velocity, E 16, S 6
38 gr H4350, BR-4 Primer, Berger 130 VLD, .010” in lands (2.803” OAL), 2752 fps mean velocity, E 21, S 8
39 gr H4350, BR-4 Primer, Berger 130 VLD, .010” in lands (2.803” OAL), 2818 fps mean velocity, E 35, S 13 (one odd shot about 21 fps faster than next lower velocity and made E 35).
40 gr H4350, BR-4 Primer, Berger 130 VLD, .010” in lands (2.803” OAL), 2895 fps mean velocity, E 8, S 3 - No pressure signs, load probably has .5 gr. to 1.5 gr. more to go before pressure issues in the rifle.
38 gr H4350, BR-4 Primer, Sierra 142, .012” jump (2.747” OAL), 2681 fps mean velocity, E 19, S 8
39 gr H4350, BR-4 Primer, Sierra 142, .012” jump (2.747” OAL), 2747 fps mean velocity, E 37, S 13 (load under minor compression - can hear a slight crunch when you seat bullet).
40 gr H4350, BR-4 Primer, Sierra 142, .012” jump (2.747” OAL), 2812 fps mean velocity, E 22, S 8 (load under compression and maybe room to squeeze .5 to 1.5 grains more powder in there but that's about it). No pressure signs or issues, but it seemed the load was approaching max, although not yet there. 2850 fps is probably do-able, but probably, above that, pressure issues will be apparent, and whether good accuracy can be obtained at 2850 fps would need to be determined as well.
There were no pressure issues with any of the H4350 loadings but with the 142 Sierra at the top loading tested (40 gr of H4350), the load is under compression, and while there may be the ability to squeeze a little more powder in there and still have no issues seating the bullet, it seemed like it was getting pretty close. H4350 is about as bulky a powder as you would want to consider using in the case.
Chronograph Testing (October 13, 2006)
37.5 gr of RL 15, BR-4 Primer, Lapua 123, in lands .010 (about 2.753" OAL) - 2966 Mean Velocity, ES 4, SD 2. This loading was found to be exceptionally accurate in the rifle, and considering the Lapua 123 Scenar has a .547 stated B.C., it is clear that the 6.5 x 47 Lapua can match the wind drift numbers and performance of the best of the 6mm "across the course" type cartridges (i.e. 6XC, 6mm/22-250, 243 Win, etc.).
37.8 gr RL 15 (a different lot than above from a different 5 lb can, because author was running out of the other lot), BR-4 Primer, Lapua 123, in lands .010" (about 2.753" OAL) - 3023 Mean Velocity, ES 15, SD 5 - this load was a little hot and had a sticky bolt lift on a number of cases so it needs to be backed off a half grain or so.
General Comments on the 6.5 x 47 Lapua:
The cartridge seems to be extremely accurate for high power rifle shooting. After setting up the rifle and doing some quick chrono testing, this author shot the last 10 rounds prone at a 100 yard slow prone target, and came up with a 10x clean. The load was 37gr RL15, a BR-4 primer, with a Sierra 120 MatchKing and .015" jump (around 2.650" OAL). Trying out a 600 yard loading, another 10x clean was shot shooting the Lapua 123's at 2969 fps with 37.5 gr of RL15 with a CCI BR-4 primer and the Lapua 123 stuck in the lands .010" (around 2.753" OAL). The Lapua 123's shot also measure .2645" in diameter, and since they are a little "fat", they do run the pressures up over the 120 and 123 Sierras that run pretty true to .264" in diameter. For the short lines the 120 Sierras shoot with stellar accuracy whether you jump them or not, and they seem to shoot just as well if you shoot them at 2800 fps or up to 3000 fps. For 600 yards, the 123 Scenar offers a great B.C. (.547) with great accuracy and velocity as well. Definitely a cartridge worth looking into for across the course shooting as well as other types of shooting and competitions.
also lots of good info here:
6mmBR.com -- Best Guide to 6mm BR Rifle Shooting and 6BR Reloading