Use this weapon line after you installed the model and the sound.
Ensure it replaces MP5K.

	<weapon type="MP5">
		<data slot="SMG" firetype="INSTANT_HIT" damagetype="BULLET" group="SMG" targetrange="15.0" weaponrange="535.0" clipsize="45" ammomax="450" timebetweenshots="66">
			<damage base="20" networkplayermod="2.5" networkpedmod="1.25"/>
			<physics force="30.0"/>
			<reload time="1666" fasttime="1666" crouchtime="2533"/>

			<aiming accuracy="0.6375">
				<offset x="0.13" y="1.0" z="0.45"/>
				<crouchedoffset x="0.11" y="1.0" z="-0.02"/>
				<reticule standing="0.75" ducked="0.6" scale="0.3"/>
			</aiming>

			<pickup regentime="360000" ammoonstreet="20"/>

			<controller>
				<rumble duration="100" intensity="0.02"/>
			</controller>

			<flags>
				<flag>GUN</flag>
				<flag>CAN_AIM</flag>
				<flag>ANIM_RELOAD</flag>
				<flag>CAN_FREE_AIM</flag>
				<flag>ANIM_CROUCH_FIRE</flag>
				<flag>TREAT_AS_2HANDED_IN_COVER</flag>
			</flags>
		</data>

		<assets model="w_mp5">
			<anim group="gun@mp5k" meleegroup1="firearm_core">
				<rates firerate="1.1" blindfirerate="1.1"/>
			</anim>
			<effects>
				<muzzle fx="muz_smg"/>
				<shell fx="weap_ejected_smg"/>
			</effects>
		</assets>
	</weapon>
