Don't worry about net savvy
I think that being net savvy would be a bad thing!
I'll get things started then others can shoot me out of the water.
From a quick read of your post you:
- Shoot a rig that has shotgun and rifle interchangeable barrels and,
- Have noticed a large difference between the performance of lead core bullets as compared to solid copper bullets.
With those assumptions in my head, here's my answer to your question. (grain of salt goes here, no smiley face for that
Back in the day Lost River made some very fine solid bullets with a bronze point. They worked great in some barrels and not for squat in others. The barrels they worked in, for the most part, were tight bored barrels such as the Lilja barrels. These are known to be "tight" bored. In factory barrels with their larger bore size these bullets were fairly useless, for the most part.
The difference between solid and lead core bullets regarding internal ballistics is that solid bullets do not
swell/expand upon firing. Lead core bullet do!
Thus with bullet diameter and bore diameter is more critical (my opinion).
You'll notice that many of the newer solid bullets are banded which helps to solve this problem while allowing lower pressures and higher velocities.
I don't know what make and model of shot/gun you are using but would suggest that if you're stuck with using non-toxic bullets that a "custom" barrel would increase your odds of having a shooter. Having said that I would suppose that Barnes or other offerings could be found to do the job.
I don't think you'll know until you try.
I have no experience with a gun that has both shotgun and rifle barrels, other than my grandson's Rossi 22/410
, so I've gone about as far as I should.
PS: If one cartridge/caliber shoots 'em any better than any other I'm sure it'll be a 270 Winchester