I git my new sizing die the other day and sized my .446" dia bullets down to .444" now with two wraps of 9lb Onion Skin paper the bullet measures .450" and is a nice slip fit into the barrel. I cast some up and patched them wet for use today, the end result was five shots into just over 2" and a flyer 5'' left and another about the same distance low at 6 o'clock. As my present patching skill may leave something to be desired the problem my lie there.
For what it's worth the load was 77gr of PP Wano with a .030" LDPE wad. On top of that was  Felt Wonder Wad and then then  the bullet. No neck tension, bullet was a slip fit and could be easily pulled out.
Mike.
PS Rifle was wiped after each shot, one damp patch, one dry.
Mike.

Mick,  it looks like you are making good progress.  One thing that is a very big factor with PP bullets, much more so than with GG, is fouling control.  All of my rifles shoot best with at least two damp patches and one dry.  I've played with a single damp and a dry in order to see if I could get my routine fast enough for silhouette but was dissapointed with the resulting inconsistent accuracy.  

In a rifle not chambered specifically for bore diameter PP bullets, the wad stack is crucial.  Often flyers happen when your bullet gets gas cut.  If your rifle is chambered specifically for bore diameter PP bullets then the rifle will be much less picky about wads.

In my "standard chamber" rifles I either use a lube cookie, or two 0.060" LDPE wads to ensure a good seal.  Or breech seat, which works very well.

Chris.

tried out unpatched bullets in the MH mk 3 
.458/459 500gn 3 grooved ex pedersoli mould , and could hold my target :27cm on 35 cm pistol silhouette  at 100 m used 19gn of vihta N340  plus dacron cloud  as keeper over the charge  , 10 by 10 cm groups 
was very surprised of the results 
greetings from a overponder 
jarmann

Unfortunately there is a bit of a problem here regarding powder availability, it's either Wano or Swiss. I know this seems like a no brainer but you can't ship powder interstate in Australia without a special permit.
Wano sold in Australia is labelled Wano and comes in three different quality grades as well as the usual granulations.
The first grade, and the cheapest is FA, I think the main use for this is in the manufacture of fireworks and for battlefield simulations by the army who just want a bang and some smoke. The second grade up are the F grades, 1F, 2F, 3F , and 4F, this is the second cheapest and works fine, say for offhand shooting and shotguns.
The premium Wano is P grade, 1P, 2P, 3P, and 4P, this  is what most of us use for serious target shooting.
I have spent a considerable amount of time testing PP wano against Swiss 1 1/2 in  both my 45/70 and the 45/90 and as far as accuracy goes there is hardly any difference that I can detect on the target, IF you clean between shots.
Having said that there is a difference in explosive strength. As an example, 80 gr of PP Wano under a 530gr GG bullet in my 45/90 gives an average MV of 1245 fps for five shots, with an extreme spread of 9 fps.
In the same rifle using the same bullet 72 gr of Swiss 1 1/2 gave an average speed of 1255 fps with a spread of 12 fps.
Given this information you would be forgiven for thinking that why not use the lesser charge of Swiss rather than the Wano. There are two reasons, firstly you can't buy Swiss powder where I live, and secondly Wano is A$50.00 per kilo, Swiss is A$110.00, the price difference makes a compelling argument when you use at least a kilo a month.
On the subject of accuracy the best group I have measured from the 45/90 at 100 meters using Swiss was 7/8" center  to center. For Wano my best was 15/16", both  shot on perfect days with a 24x scope on the rifle, off the bench.
If I can get my PP bullets to shoot this well I will me more than happy.
Mike.