There are no set in stone rules. Common, simple safety covers most everything. Casting for a .38 is no different than for a .223. The bullet selection may change. Rifles, small bore more so, are best served by very fast bullets and jackets make that more practical. So, super fast is limited, add at the other end, weight. Here comes the rub. That super small bore with the fast twist just may or may not like your slow(er) heavy (longer) bullets.
Things to contemplate:
Heavy is more energy - small bore makes that bullet longer - lots of good lube is great help - hard only helps to a point.
There is a fear that lead will be stripped off and clog/block the barrels gas port (on auto loaders with them). I will not say that this can't happen. I have pushed lead out of Garands with no sign of any lead in the gas system. Same for 66 grain pills out of an AR-180 (no they didn't stabilize well - 1 in 12 twist) and I found no lead in the gas system. The boys loading up suppressed 300 Blackouts often used very heavy lead (the twists are balanced for this) and no one is complaining about lead in their DI gas M4s.
I gave up on lead out of first a .222 Rem followed with .223 Rem/5.56. It ended up being a lot of work for a little better .22 RF.
Now lead out of an '06 or 303 Brit is another matter.
Don't push lead hard and watch those super volume cases with so little propellant in side.
One other thing, super clean that barrel when switch from jackets to lead or back.
Be safe and enjoy.