Best RL powder for 470 NE

[Surgeon1]

Heym 88B
I use IMR3031 with 500gr A-Frame
Federal 215 mag primer
Norma or federal cases
79.5gr with 2gr Dacron fiber
Gives very consistent 2145fps

Have used Kynoch wads with 79.0gr but velocity has bigger SD and not quite as tite a group on 4 shots
about 2.5-3" at 55yds vs 1.7-2"
Have also used 1/2" open cell backing rod as a filler cut to length then tamped in with a wood dowel.
It is more consistent than Kynoch wads, and I use it exclusively in my 450-400 with 3/8" backing rod
I've tried the slower burning powders like IMR4350, 4064, RL19 & 22, & 4831 with varying results...more
recoil worse accuracy.

 

[rookhawk]

Heym 88B
I use IMR3031 with 500gr A-Frame
Federal 215 mag primer
Norma or federal cases
79.5gr with 2gr Dacron fiber
Gives very consistent 2145fps

Have used Kynoch wads with 79.0gr but velocity has bigger SD and not quite as tite a group on 4 shots
about 2.5-3" at 55yds vs 1.7-2"
Have also used 1/2" open cell backing rod as a filler cut to length then tamped in with a wood dowel.
It is more consistent than Kynoch wads, and I use it exclusively in my 450-400 with 3/8" backing rod
I've tried the slower burning powders like IMR4350, 4064, RL19 & 22, & 4831 with varying results...more
recoil worse accuracy.

This load is above normal operating pressures as published. I would be very careful with it.

Max load is somewhere around 77.5gr I believe. Obviously with a modern Heym you may be able to get a little wiggle room, but nobody else gets that wiggle room. Also, in addition to a beyond max load, 2gr of Dacron fluff would push the pressure up even more compared to a wad.

Be careful and never copy this load with a vintage British double.

 

[MacJenkins]

This load is above normal operating pressures as published. I would be very careful with it.

Max load is somewhere around 77.5gr I believe. Obviously with a modern Heym you may be able to get a little wiggle room, but nobody else gets that wiggle room. Also, in addition to a beyond max load, 2gr of Dacron fluff would push the pressure up even more compared to a wad.

Be careful and never copy this load with a vintage British double.

Agreed, I have replaced Dacron with foam backer rod in all my doubles. So much simpler and better results. Hell of a lot less messy when shooting as well.

 

[rookhawk]

Agreed, I have replaced Dacron with foam backer rod in all my doubles. So much simpler and better results. Hell of a lot less messy when shooting as well.

I haven’t gone that far, the stuffing produces a different regulation than the backer rod. The former must be shot at lower grains of gun powder than a latter but its another tool available to use in an attempt to regulate a double.

I would exhaust every possible angle of getting 3031 to regulate exceptionally before I would resign myself to RL15, or worse yet 4350, or absolutely worse yet 4831.

 

[deewayne2003]

When I switched from Dacron to Kynoch wads, my regulation didn't change at all with 3031 in my .470

 

[rookhawk]

When I switched from Dacron to Kynoch wads, my regulation didn't change at all with 3031 in my .470

@Wahoo might have some information to share. He recently regulated his 470NE and was finding a significant difference in velocity and perceived recoil by swapping between dacron stuffing and kynoch wads. His conclusion matched info I have heard from others that you can get different regulation and by testing both, you may find one to be ideal and the other to be less than.

 

[deewayne2003]

@Wahoo might have some information to share. He recently regulated his 470NE and was finding a significant difference in velocity and perceived recoil by swapping between dacron stuffing and kynoch wads. His conclusion matched info I have heard from others that you can get different regulation and by testing both, you may find one to be ideal and the other to be less than.

Not doubting you one bit, but in my .470ne I chronographed both Dacron and Wads with no change in velocity, recoil or regulation.

I made the shift to wads because of the lower pressure and easier reloading.

On another note I tried RL22 powder - the recoil was much more with RL22 and while the Woodleigh manual states 110gr powder charge Aliant load data says 117gr powder charge and that's what it took to get the bullets to properly converge.