Can I make items bigger?

I'm trying to make a spear. But it's the same lenght as a sword. Are there any ways to get it look bigger (while held by player)? I would accept any solution, involving commands, item textures and models (working with res.pack).

Solution 1:

Sorry everybody, I figured it out on my own! In resource pack there's an easy way to make items as big as you want!

{
"parent": "item/generated",
"display": {
    "thirdperson_righthand": {
        "rotation": [ 0, -90, 55 ],
        "translation": [ 0, 4.0, 0.5 ],
        "scale": [ 2, 2, 2 ]
    },
    "thirdperson_lefthand": {
        "rotation": [ 0, 90, -55 ],
        "translation": [ 0, 4.0, 0.5 ],
        "scale": [ 2, 2, 2 ]
    },
    "firstperson_righthand": {
        "rotation": [ 0, -90, 25 ],
        "translation": [ 1.13, 3.2, 1.13 ],
        "scale": [ 2, 2, 2 ]
    },
    "firstperson_lefthand": {
        "rotation": [ 0, 90, -25 ],
        "translation": [ 1.13, 3.2, 1.13 ],
        "scale": [ 2, 2, 2 ]
    }
},
"textures": {
    "layer0": "items/diamond_sword"
}
}

So, yes, you can change the size of items. P.S. Sorry for this massive pile of text, one could call code.