Nice. What are you going to use it on? The Para lance?
I'm fond of Bloodguilty Maw. It's a 0.9 barrel so it's only mediocre for Pierce but RF Poison can be loads of fun. Really only effective on Uragaan, Barroth and Diablos - each volley is worth 75 Poison (100 with Bonus Shot). With Combines and Poison lv2, you can theoretically poison Uragaan 8 times! Also, Bloodguilty Maw is an awesome name.
If language were liquid, it would be rushing in. And yet here we are in a silence more eloquent than any words could ever be.