I agree with FG, Guns are not just going to burst on their own and are also proofed to a load that is much higher than the recomened load that are most accurate for the gun/rifle. I have only seen one burst barrel in my life and it was a m/l loader with smokeless powder. The jack@#$ who did it had some nice sharp shards of steel go into his arm. He also felt so bad at what he did he gave the blown up gun to a local shop mounted with a sign underneith stating "Never use smokeless powder in a m/l".

As long as you follow the manual that came with your rifle you should be fine and I also agree that some sort of gas port may cause more harm than good.