Ran a little test today. I'm having a Lt weight hunting rifle built by Chris Matthews of Longshot Rifles http://www.longshotriflesllc.com/ , possibly in 6.5x47 Lapua or 260 Rem AI and wanted to see what a 140 gr bullet with Rel 17 would do. So, I took my tactical rifle, also built by Chris, and ran a pressure ladder with it.

Surgeon 591 short action
Krieger 26" 1:8.5 twist, SS, MTU contour
1.5 AICS stock
NF NXS 5.5-22x50 w/ NP-R1 reticle
Shilen 2lb trigger

6.5x47 Lapua brass w/ 5x firings
Berger 140 VLD Hunting
Nosler 140 Accubond

37 gr to 43 gr in .5 gr increments (42.5 gr w/ Accubond due to mucho compression)
CCI 450 primer
Throat started life @ .105" long but after 700+ rounds is now .161" long.

Temp 57 deg F
Baro 24.6
Chrono = CED M2 set 15' from muzzle

140 VLD's were seated .010" into the lands with OAL being 2.797".

140 Accubond's were seated @ the lands with OAL being 2.698". Had to turn down my Redding comp seater about .005" for each successive round after 39.5 gr.

37 2521
37.5 2533
38 2587
38.5 2614
39 2647
39.5 2682
40 2707
40.5 2770
41 2814 ? ejector mark
41.5 2863 Light ejec
42 2910 Light ejec
42.5 2922 ejec
43 2962 ejec/bolt lift

Pressure ladder test for Rel 17
Nosler 140 Accubond
37 2513
37.5 2537
38 2569
38.5 2612
39 2634
39.5 2682
40 2716 ?ejec
40.5 2760
41 2770
41.5 2834 Lt ejec
42 2863 ejec
42.5 2910 ejec

I was pleasantly surprised @ the vel obtained in the little x47mm case with Rel 17. I think I'll hunt with it instead of going 260 Rem AI.

Enjoy!

Alan

I used rl-17 in my 7saum this last hunting season. 62grs with a 139gr Hornady spire point, dont know the velocity but it rolled a nice doe. There was no signs of high pressure, the factory 150gr core-lokt has hard bolt lift, and its definately runnin real hot. Check out www.6mmbr.com they have good reports on rl-17

Alan, great info, thanks for the post/reporting the findings.

GSSP,
I am mildly suprised you reached those velocities with that slow of powder, even though you have a 26" barrel. I would think that RL-15 would be a better fit. Please do not take my comment as beeing critical, it is not meant that way. Do you have any plans to use RL-15 in any loads? As you can tell my favorite powder is RL-15 and any rifle it shoots well in.(Most all of the rifles I have tried have preferred it.)
Thanks, Doug