What Curl means by 'lighter' loads is those loads that produce low pressure. Look for loads with the same weight projectile that produce between 7,00LUP and 8,500 units of pressure. (low in whichever they use). Then, you can go from there in your own load development, depending on the gun. This is how I developed my data so many years ago in the double shotgun, I converted into a smooth double rifle.(smoothbore, rifle sights).

Typically, Blue Dot, Herco, Unique, 800X, SR7625 and SR4756 are used. there are Hodgdon slow powders are well - Longshot has a great deal of potential.

Of course, this is all for smokeless guns.

Oh yeah - one other thing, Lyman used to make roll crimpers. Anyone with a lathe should be able to make one in about 30 min. or less, given the right sized material. The Lyman roll crimpers were held in the jaws of a drill press. I suspect a hand drill would also work - 3/8" jaws. The addition of wax helps seal and form paper case roll crimps.