Machine Gunner (5e Feat)

Prerequisites: proficiency with firearms
You are the shadow of death on wheels with a big gun in your hands. You gain the following benefits:

You gain a +1 bonus to attack rolls with weapons that have the burst fire properties.
When you make a burst fire attack, the Dexterity saving throws to avoid taking damage is 20, rather than 15.
When you make a burst fire attack, you may choose to strafe a 5-by-20 foot area, rather than attacking a 10-by-10 foot area.
When you make a firearm that has the burst fire trait and at least 40 shots remaining, you can choose to fire a heavy burst. Treat a heavy burst as a burst fire attack, except you may affect a 20-by-20 foot cube, or you may choose to strafe a 10-by-40 foot area.
Once on your turn, when you hit with with an attack with a firearm that has the burst fire property, you may roll the damage of your attack twice and take the higher result.