Though it works fine when I remove other mods. Is there any reason for this? It also happens with other gun/ranged weapon mods such as Mr. Crayfish's.

Modlist:

Air Support

Ambient Environment

AmbientSounds

Animalium

AppleCore

AppleSkin

Backpacked

Bad Mobs

Better Burning

Biomes O' Plenty

BiomeTweaker

Campfire Spit

CodeChicken Lib

Comforts

CoroUtil Library

CraftTweaker 2

CreativeCore

Dynamic Surroundings

Dynamic Trees

Dynamic Trees BOP

Food Funk

Grappling Hook Mod

Hero Aviation Helicopters

Howl

Hunger Overhaul

Immersive Vehicles

InControl

Just Another Rotten Flesh to Leather Mod

Localized Weather

The Lost Cities

Macaw's Bridges

MineTraps

MineTweaker Recipe Maker

Mob Sunscreen

MrCrayfish's Guns

Not Enough Items

Obfuscate

OMLib

Open Modular Turrets

Optifine

OreLib Support Mod

Pam's Clay Spawn

Realistic Torches

Sanity

Scaling Health

Scape & Run Parasites

Serene Seasons

Silent Lib

Sound Filters

Techguns

TiffitLib

Tough As Nails

Tumbleweed

UniDict

WanionLib

Weapons of the Apocalypse

Wumple Util Library

Xaero's Minimap

Zombie Awareness

Zombie Players

Found out the conflicting mod was Immersive Vehicles. Still no idea why though.