Let me start this by saying that I am not into competitive shooting but love to tune my rifles to deliver the best that they have.  I recently bought a 32/40 HiWall and with help from many of the members here I have progressed with my learning curve on breech seating for this fine old rifle.  I am now starting to shoot better groups with consistency and learning why my shots are heading outside of my group.  I have decided that there are many factors involved in fine tuning a rifle and load and several I have no control of at this time.  First is the rifle.  It is what I have and maybe it is not capable of shooting a 250, but it is what I am using.  Second are the bullets.  I am buying tapered 170 grain bullets and until I decide to buy casting gear or sweet talk one of the members here to sell me match grade bullets I am stuck shooting these.  Now for the factors that I do have, or should have, control of.  The sights I am using are a 8x32 Burris which in its day was a very fine varmint scope and is easy to adjust the parallax at the 100 yards I am shooting.  I am satisfied with it.  Next is the brass.  I made brass from Starline 38/55 long and have picked out 5 cases.  The next factor is bench technique and I am working on that and getting much better with setup.  I am resting in the same place on the barrel for now until I figure out the powder charge but that might be a mistake.  It seems like one of the last things to change unless I am getting extreme vertical.  The next most important I think is reading the wind and I am using two flags, one at 16 and the other at 50.  We only have a 20 minute shooting window so I can't always wait for the condition to return but return to the sighter and see where to hold off.  This leaves me with the easiest to change.  I have been using 14.0 and 14.5 gr of IMR 4227 and 12.8 of AA#9.  Are these charges in the ballpark and should I start at 14.0 and load up in 0.2 gr increments.  I premeasure at home and carry the powder in vials.  I am seating the bullets to engrave 1/2 of the base band leaving that variable unchanged.  Next is the primer.  I have been using CCI and Win LR as that is what I have and also got some CCI LP to try with the AA#9.  Primer selection is scarce where I live but I am going to be going by a large store in 2 weeks and can pick up different primers if you think I should.  Any thoughts on what order I should start changing the variables as I am finally getting good enough to see results.  Tom

Thanks Frank.  If the weather settles down I plan on shooting Thursday and will up my powder somewhat.  I also plan on shooting some paper patched bullets in my 38/56 Rolling Block trying to work up an accurate hunting load.

The AA #9 made in Australia or Belgium has been better quality than the AA #9 I have used that were manufactured in Isreal and USA.

AA 4100 is made in Belgium and is basically the same as AA #9 or use MP 300 as Frank suggests.

My rifles preferred loads of 12.4 to 13.0 grains.

Are the bullets that you are buying lead and tin or are they hard cast Tom. 

Tom unfortunately I can be of no help with the 40-65 not having any personal experience with it myself.

For the .40-65 I use fixed cartridges with 52.7 grains of Swiss FFFg (1,250 fps) with a newspaper wad over the flash channel and a .060" vegetable wad over the BP compressed .230" after dropping the BP with a drop tube. I use Remington 9 1/2 M primers in Starline cases which are annealed before using. I use a 410 grain Boomer Money bullet in my 16:1 twist Shiloh barrel.

I use fired unsized cases and take the bell out of the loaded case by using a necking die to crimp the neck straight.

This is light recoil load.

Gyroscopic Spin Factor (Sg):

Caliber      0.408      Inches            
Bullet Weight      410      Grains            
Bullet Length      1.44      Inches            
Barrel Twist      16      Inches/turn            
muzzle velocity      1250      fps            
Temperature      50      degrees Fahrenheit (59 is standard)            
Pressure      29.92      inches of mercury (29.92 is standard)            
                       
Sg =      1.86                  
                       
Sg shouldn't be less than 1.4 (not spinning fast enough).  If Sg is greater than about 2.0 (overspinning bullet), you may                        
gain some accuracy by going to a slower twist barrel or using a longer bullet.                        

I only breech seat my .25 (quarterbore)and my .32 Schuetzen rifles.

Continued.. i have no idea how the last got posted as i never intended to post yet.. 
ok the winner is no filler at all real kapok came in a close second but still gets beat by no filler wad or anything. 
seating depth.  I made an adjustable plugged case and take a 4 inch caliper in my kit and write down the exact measurment of the plugged case. seating 15 to 20 thou. makes a lot of difference. better groups.
powder.. I have tried several and either aa9 or 4759 have been about equal. I really cant tell which is best as one time one will shoot just a bit better than the other and then it reverses results. I have found that liter charges than recommended has shot best. 12.8  to 13 gr. of sr4759 or 11.8 gr. of aa#9. Heavier charges of both have been tried several times and just dont shoot as well. I am not the greatest shot in the country but sure have a lot of fun trying to get smaller groups every time I go to the range. 

Dave, I have a 1:16 twist original HiWall barrel.  Slowly but surely following your advice as well as from others I am starting to get a little more dialed in.  I found a somewhat sweet spot at 14.8 grains of IMR 4227 behind a 170 grain tapered Saeco bullet and another at 15.5 grains.  I am going to load some at 14.7, 14.8,14.9 15.4, 15.5 and 15.6 in vials for my next trip.  I cannot shoot long strings very easy as we have a 20 minute shooting time before cease fires to change targets and so for exploring I have been shooting every 0.2 grains to see what the pattern is.  If a 5 shot group is not showing promise I quit and jump up to the next charge.  I figure in 143,525 more shots I will catch up with JLouis!    It is encouraging that my good groups are getting smaller so I can tell if the powder charge is getting close.  The load pictured with 15.5 rounds was shot in a prevailing condition from about 10 degrees so I had a hard time seeing how the tail flags were hanging and had to judge the spin on the daisy wheel.  That one shot that is high could have easily been a let up in the wind.  I have always hated shooting with a head wind and much prefer a side wind.  It was quite a thrill to have several shooters stop and watch me breech seat as they had never heard of it before and then when they saw the groups several remarked on the accuracy.  I told them that the "big boys" could keep them all in the white bull but I was getting better slow but sure.  Thanks to all for the suggestions.  Tom