Reloading lead for polygonal rifling requires extremely close attention to detail.  Not for the inexperienced.  In fact, I am the new owner of a Lone Wolf Barrel for my glock, now I can push the lead a little bit harder.

For the OP, there is no problem with loading lead, just keep an eye out for leading of the barrel, if you get that you need to back it off a little bit.

Well, I wouldn't go so far as to say "back off" the load if leading occurs.  Leading can occur if the bullet alloy is too hard, too soft, if the bullets are undersized, or if the load is pushing the bullet too fast (similar to "too soft" alloy).  The right combination of all of the above can fix a leading problem, or cause it.  Leading is generally due to gas-cutting, that is, chamber gas gets around the bullet from behind it and cuts lead off the base of the bullet, depositing it in the rifling.  A bullet 0.001" or even 0.002" oversize can help prevent this, which initially might seem counter-intuitive, using a larger diameter bullet to NOT get leading.  Likewise, a too-hard bullet alloy may not deform under pressure from behind and seal up the bore. 

I'm at work now and John Ross' website (Ross in Range) is blocked, but he has a nice little piece there about handloading lead rounds for 44Mag and 50(50AE I think).  He lays all this out much more authoritatively and with much more experience than I.

Another work-around would be to use case filler between the powder and the bullet.  The filler gets pushed up against the base of the bullet and serves as a gas check.  Most fillers when compressed that way also serve to scrub any existing leading out of the barrel.  There's at least one commercial product for this, really tiny little plastic balls so fine they flow like a liquid.  If you're cheap like me, uncooked cream of wheat cereal works well.

Couple of downsides or potential downsides.  One is to carefully work up any loads for which you use fillers.  The mass of the filler is getting pushed out of the barrel in addition to the bullet, so pressures will be a little higher than with bullet alone.  Also, even though it's compressible, the filler will reduce the volume inside the chamber into which the gases can expand, which will raise pressures.  And finally, powder burn rates are affected in a non-linear fashion by chamber pressure, with high pressures leading to much faster burn rates and thus higher pressures.  Carefully work up any loads with filler.

Another downside is that adding the filler material adds another step to the reloading process, which makes it go slower. 

That said, I've had a lot of success using cream of wheat filler in pistol using W231 powder (9mm, 357, 40, and 45) as well as with cast bullets in rifles with BL-C(2) and several IMR powders.  I use cream of wheat filler in all my cast rifle bullet loads.  I'm still tinkering and adjusting, but I can push lead bullets faster than will allow them to spin stabilize, like 2300 fps, with no leading and no gas check other than the filler material.  I slow the cast bullets down so that they'll grip the rifling and will spin stabilize, but that's the only concern, leading is not a problem at all.  I love plinking with my 30 Carbine and being able to use my own cast bullets in it means I can plink for less than 10 cents each (just powder and primer) all I want, so long as I don't mind spending a lot of hobby time reloading.  Ditto for my 8mm Mauser and 7.62x39 rifles.  Even for 357 magnum, I like being able to make some pretty hot cast bullet loads and not worry about leading.

So, you could potentially try shooting lead bullets with some filler in a polygonally-rifled barrel.  For pistol I usually only make limited amounts of these, because it's extra hassle to have to add the filler.  At the end of a range session shooting lead bullets, I'll run 15 or 20 of the cream of wheat rounds through the gun to clean out the barrel.