I have used Vihtavouri N550 and N560 in different rifles and
I found that N550 to be very similar in burning rate to H414, and about 0.5 to 1.0 grain faster than H4350 in my .17/222 Mag imp (Water Capacity 31.5 grains) with 30 grain bullets. ie:
27.5 grains Viht N550 - 4075 fps (Max)
27.0 grains WIN 760 - 4013 fps (Max)
27.5 grains H414 - 4057 fps (Max)
28.0 grains H4350- 3878 fps (Near Max)
28.0 grains Viht N560- 3625 fps (Mild)
Judging from the above Vihtavouri N550 would be to fast for the cases you mention, except for the lightest bullets in each calibre.
I have tried N560 in my .22/250 imp, .224 Clark (22/257 Roberts Imp), and 25/06 AI.
In the 22/250 imp (Water Capacity 49.3 grains) it was about 0.5 grains faster than H4831sc with the 69 grain bullet. ie
43.5 grains N560 - 3326 fps (Maximum)
43.5 grains WIN WXR - 3439 fps (Maximum)
44.0 grains H4831sc - 3260 fps (Maximum)
44.0 grains Re 22 - 3416 fps (Maximum)
44.5 grains Viht N165-3378 fps (Near Max)
46.0 grains WIN WMR - 3428 fps (Near Max)
In the .224 Clark (Water Capacity 64 grains) it was about 0.5 grains faster than H4381 with the 69 grain bullet. ie:
52.0 grains IMR 4831- 3931 fps (Max)
54.0 grains N560 - 3842 fps (Max)
54.5 grains H4831 -3859 fps (Max)
54.5 grains WIN785 -3876 fps (Max)
54.5 grains IMR 7828 -3946 fps (Max)
In the 25/06 AI (Water Capacity 72 grains) it was about 1 grain faster than H4831sc with the Nosler 100 grain BT. ie:
59.0 grains IMR4831 - 3523 fps (Max)
61.0 grains N560 - 3520 fps (Max)
62.0 grains H4831sc - 3479 fps (Max)
63.0 grains Viht N165-3591 fps (Max)
64.0 grains WIN WMR - 3596 fps (Max)
Judging from the above Viht N560 could be useful in the cases you mention with the lighter to medium weight bullets. However, it would certainly be too fast for the heavier bullets which are best suited for the cases you mention.
However, as you can see from my results both N550 and N560 have not given higher velocities than other powders of similar burning rate, which is contrary to the hype in their advertising material on their high energy series of powders. Hope the above helps. Brian
