M*CARBO Brotherhood

Unique powder in Ruger 77/357 reloads

I use a Lee precision powder measure on my Lee load master press, I decided to use Unique for reloading 357 calibre 158gr copper plated heads (that’s all that’s available). Using Lead load data as recommended by the bullet manufacturers, and the lee reloading manual between 6.5 grains and 6.8 grains), In order to ensure the bullet gets out of the 16inch barrel,
Lee recommends disc .71 for 6.5 grains yet that only gives out 5.5 grains of Unique when i weigh them, so i moved it to disk .82 ( should be for 7.5 grains yet still only dispenses between 5.9 and 6.2grains, ) Lee advises of potential 15% discrepancy with Unique powder, has any one else had this issue at all?
I know its large flakes but its doing my nut in with the inconsistencies and trying to sort it.


Unique is the only powder I use to load .357 and .44mag. I like it because its relatively clean burning and gives good velocities. The clean burn is nice for revolvers.

I use an ancient rcbs thrower and a trickle charger and weigh every charge, so the flakes don’t really cause me any trouble.

I dont have a progressive press, so I’m afraid I’m not much help.

Kinda jealous of that rifle though…

Wish I would have bought one (and a 77/44) when they were available for a reasonable price in blued/wood furniture configuration.


Thanks for the reply, decided to use my electronic Lyman gen 5 powder gadget to
weigh the loads individually ( pain in the rear but accurate) The Lee disks are well off I decided i will print a sheet off with all their disk sizes and measure the actual powder they dispense for different powders and write them down, i know temperature and batches affect it but maybe a general list will be achieved, maybe useful to others, will post it in a few weeks/ months see if any one else gets similar.

I should add a note i don’t use load data provided by other people just in case it goes boom or pop instead of bang


I had the same problem years ago using a lee perfect powder measure. Using the micrometer settings as per lee for unique I would get different readings. I found a door knocker and mounted it to the stand and positioned it so I could flip it up and it would come down on the measure stand to pack the unique better. I would flip it twice. Always gad good readings after that. I advised a friend to do the same and his worked better also.
Hope this helps.