Reducing charges for lead projectiles.

I reload for four rifle calibers. In order of adoption they were .303 British, 30/30 Winchester, .243 Winchester and .223 Remington.

When I first started reloading (.303 only) I used a Winchester powder. About the time I moved into loading 30/30 (early 1990's) Winchester powders were a bit hard to come by so I bought some ADI AR2208 which I could use for both calibres. When the .243 came along I found loadings for it using 2208, same for the .223 so I saw no need to change.

Today I went to get a new can of powder only to find it was now one third ($80 compared to $60) more than another powder I can source locally. This second powder is a locally packaged and sold version of a "well known" (first developed in 1933 and manufactured by several companies at times since) powder but is not named and is rated as being between AR2206H and AR2208 in burning rate (all this from the distributer/packaging website). The ADI website lists loads for all the calibre's and bullet weights I use for both 2206H and 2208 so selecting starting and safe maximum loads is not an issue, for jacketed projectiles!

My problem is that I also shoot lead projectiles in both the .303 and 30/30 for CAS (the 30/30 for long range lever action rifle and the .303 in a Martini action for single shot long range).

My pistol reloading has taught me to reduce jacketed loads when using lead projectiles so..... How much should I reduce the loads for the lead projectiles if I go with this new powder? Is 1 grain for both starting and maximum loads sufficient if I chose a mid range load?

What weight bullets in both cases? Gas checked? 2208 may not be sutable for all.
looking at lymans 303 data they do not list a load for 2208 for the 200gr cast but minimum load for 174 and 180gr jacketed just sneak under 2000fps so may be ok?

From the ADI website:

.303 British.

Bullet Powder Bullet Diam. C.O.L Starting Loads Maximum Loads
Grs Velocity (fps) Pressure Grs. Velocity (fps) Pressure

150 GR. HDY SP AR2208 .312" 3.008" 38.0 2410 35100 psi 43.4 2710 48800 psi


For the lead projectiles in both .303 and 30/30 I have some pretty old data for IMR4064 which is listed as an identical burning rate powder. Didn't worry with gas checks and kept velocity under 2,000 fps. In the Martini I used a full case of Pyrodex (didn't want to possibly ruin an old gun with smokeless loads).

Although I do confess I haven't fired the lead rounds in quite a while as I stopped CAS shooting several years ago. Just in the process of getting back into the sport now.

I load a 169gr cast in a .308 with 25grs 2206H and 27grs 2208 for around 1800fps the .303 should be safe with the same loads, cast bullets have lower pressure than jacket bullets with the same powder charge
you will get leading in the barrel before you reach high pressures and accuracy will go out the window, the case will be over half full so fillers won't be necessary if you go much lower you will need a filler
to keep the powder against the primer.