I like to use shok buffs in all my guns, but I've learned from experimenting that the Trojan 40 will simply eat EVERYTHING I put in it.
I've tried rubber buffs, and they last about 40 rounds.
I've tried aluminum buffs and they last perhaps 800-1000 rounds before leaving aluminum shards spread throughout the bottom end of the gun.
I've used skinny spring steel buffs to sandwich a rubber buff and it lasts a few thousand rounds before snapping in half, but they ALL eventually break.
I've tried the above with both a steel guiderod and a tungsten rod: no difference.
I'm not running excessive loads: just IPSC Major. So I now "go commando" with the Trojan. I have not been able to identify WHY my Trojan eats buffs (sharp edges, etc), but it consistently does.
While I'd like to soften the blow, I simply can't run the risk of bits of buff mucking up the reliability of the gun.
-ivan-