Here's my personally tweaked XM25 Grenade Launcher weapon line by me for 9SYcHO's XM25 mod, convert from San Andreas to EFLC.
Now the MW3 styled Grenade Rounds fire much farther with the awesome Physics Force.

Before starting, tweak first your TLAD or TBoGT default.ide file first, find the w_ex_glauncher (TLAD is w_e1_glauncher and TBoGT is w_e2_glauncher) and change it with this below:

w_ex_glauncher,		w_ex_glauncher,		gun@m40a1,	1,	100,	0

Note that you must change the variable to w_e1_glauncher for TLAD or w_e2_glauncher for TBoGT. Otherwise the game will crash.
Above is for MW3 styled XM25. If you want the normal style, you can change the gun@m40a1 to gun@rifle.
Save the file and close.

Now, open up the TLAD or TBoGT WeaponInfo.xml, check if the XM25 weapon line installed from 9SYcHO.
With that, you can use this line below:

MW3-styled Grenade Launcher

<!-- GRENADE LAUNCHER -->
	<weapon type="EPISODIC_1">
		<data slot="HEAVY" firetype="PROJECTILE" damagetype="EXPLOSIVE" group="GRENADE" targetrange="30.0" weaponrange="32" clipsize="4" ammomax="12" timebetweenshots="800">
			<damage networkplayermod="2.0" networkpedmod="1.0"/>
			<reload time="2066" fasttime="2066" crouchtime="2066"/>

			<aiming accuracy="0.65">
				<offset x="0.14" y="1.0" z="0.55"/>
				<crouchedoffset x="0.08" y="1.0" z="0.12"/>
				<reticule standing="0.6" ducked="0.5" scale="0.3"/>
			</aiming>

			<pickup regentime="600000" ammoonstreet="3"/>

			<controller>
				<rumble duration="100" intensity="0.8"/>
			</controller>

			<flags>
				<flag>GUN</flag>
				<flag>HEAVY</flag>
				<flag>CAN_FREE_AIM</flag>
				<flag>FIRST_PERSON</flag>
				<flag>ANIM_RELOAD</flag>
				<flag>ANIM_CROUCH_FIRE</flag>
				<!--<flag>CREATE_VISIBLE_ORDNANCE</flag>-->
				<flag>2HANDED</flag>
				<flag>HEAVY_WEAPON_USES_RIFLE_ANIMS</flag>
			</flags>

			<projectile>
				<typetocreate type="EPISODIC_5"/>
				<offset 	 x="0.55" y="0.0" z="0.08"/>
				<rotoffset x="0.0"	y="0.0" z="0.0"/>
			</projectile>
		</data>

		<assets model="w_e2_glauncher">
			<anim group="gun@m40a1"/>

			<!--	<effects> -->
				<!--	<muzzle fx="muz_grenade_launcher"/> -->
			<!--	</effects> -->
		</assets>
	</weapon>

<!-- CDTE GRENADE for GRENADE LAUNCHER (not usable as a thrown weapon on its own) -->
	<weapon type="EPISODIC_5">
<data slot="SPECIAL" firetype="PROJECTILE" damagetype="EXPLOSIVE" group="ROCKET" targetrange="35.0" clipsize="1" stattype="RLAUNCHER">
			<damage networkplayermod="2.0" networkpedmod="1.0"/>

			<aiming accuracy="1.0">
				<offset x="0.0" y="1.0" z="0.0"/>
				<crouchedoffset x="0.0" y="1.0" z="0.0"/>
				<reticule standing="0.65" ducked="0.55" scale="0.3"/>
			</aiming>

			<pickup regentime="360000" ammoonstreet="8"/>

			<controller>
				<rumble duration="0" intensity="0.0"/>
			</controller>

			<flags>
				<flag>THROWN</flag>
				<flag>ADD_SMOKE_ON_EXPLOSION</flag>
				<flag>EXPLOSION_BASED_ON_IMPACT</flag>
			</flags>

			<projectile type="ROCKET">
				<explosion type="EPISODIC_1"/>
				<physics force="200.0" explodeimpactthreshold="0.25" explodeimpactwithvehiclethreshold="0.05"/>
			</projectile>
		</data>

		<assets model="w_e2_grenade">
			<effects>
				<trail fx="weap_pipe_bomb_trail"/>
			</effects>
		</assets>
	</weapon>

Normal Grenade Launcher

<!-- GRENADE LAUNCHER -->
	<weapon type="EPISODIC_1">
		<data slot="HEAVY" firetype="PROJECTILE" damagetype="EXPLOSIVE" group="GRENADE" targetrange="30.0" weaponrange="32" clipsize="4" ammomax="12" timebetweenshots="800">
			<damage networkplayermod="2.0" networkpedmod="1.0"/>
			<reload time="2066" fasttime="2066" crouchtime="2066"/>

			<aiming accuracy="1.0">
				<offset 				x="0.15" y="1.0" z="0.53"/>
				<crouchedoffset x="0.12" y="1.0" z="0.05"/>
				<reticule standing="1.0" ducked="1.0" scale="0.0"/>
				<ordnanceoffset pitch="0.1"/>
			</aiming>

			<pickup regentime="600000" ammoonstreet="3"/>

			<controller>
				<rumble duration="100" intensity="0.8"/>
			</controller>

			<flags>
				<flag>GUN</flag>
				<flag>HEAVY</flag>
				<flag>CAN_FREE_AIM</flag>
				<flag>ANIM_RELOAD</flag>
				<flag>ANIM_CROUCH_FIRE</flag>
				<!--<flag>CREATE_VISIBLE_ORDNANCE</flag>-->
				<flag>2HANDED</flag>
				<flag>HEAVY_WEAPON_USES_RIFLE_ANIMS</flag>
			</flags>

			<projectile>
				<typetocreate type="EPISODIC_5"/>
				<offset 	 x="0.55" y="0.0" z="0.08"/>
				<rotoffset x="0.0"	y="0.0" z="0.0"/>
			</projectile>
		</data>

		<assets model="w_e2_glauncher">
			<anim group="gun@rifle"/>

			<!--	<effects> -->
				<!--	<muzzle fx="muz_grenade_launcher"/> -->
			<!--	</effects> -->
		</assets>
	</weapon>

	<!-- GRENADE for GRENADE LAUNCHER (not usable as a thrown weapon on its own) -->
	<weapon type="EPISODIC_5">
		<data slot="THROWN" firetype="PROJECTILE" damagetype="EXPLOSIVE" group="GRENADE" targetrange="1000.0" clipsize="1" stattype="EPISODIC_1">
			<damage networkplayermod="2.0" networkpedmod="1.0"/>

			<projectile type="IMPACT" fusetime="9999">
				<explosion type="EPISODIC_1"/>
				<physics force="200.0"/>
			</projectile>
		</data>

		<assets model="w_e2_grenade">
			<effects>
				<trail fx="weap_pipe_bomb_trail"/>
			</effects>
		</assets>
	</weapon>

FPV Grenade Launcher (uses scope like MW3 ones)

<!-- GRENADE LAUNCHER -->
	<weapon type="EPISODIC_1">
		<data slot="HEAVY" firetype="PROJECTILE" damagetype="EXPLOSIVE" group="GRENADE" targetrange="30.0" weaponrange="32" clipsize="4" ammomax="12" timebetweenshots="800">
			<damage networkplayermod="2.0" networkpedmod="1.0"/>
			<reload time="2066" fasttime="2066" crouchtime="2066"/>

			<aiming accuracy="1.0">
				<offset 				x="0.15" y="1.0" z="0.53"/>
				<crouchedoffset x="0.12" y="1.0" z="0.05"/>
				<reticule standing="1.0" ducked="1.0" scale="0.0"/>
				<ordnanceoffset pitch="0.1"/>
			</aiming>

			<pickup regentime="600000" ammoonstreet="3"/>

			<controller>
				<rumble duration="100" intensity="0.8"/>
			</controller>

			<flags>
				<flag>GUN</flag>
				<flag>HEAVY</flag>
				<flag>CAN_FREE_AIM</flag>
				<flag>FIRST_PERSON</flag>
				<flag>ANIM_RELOAD</flag>
				<flag>ANIM_CROUCH_FIRE</flag>
				<!--<flag>CREATE_VISIBLE_ORDNANCE</flag>-->
				<flag>2HANDED</flag>
				<flag>HEAVY_WEAPON_USES_RIFLE_ANIMS</flag>
			</flags>

			<projectile>
				<typetocreate type="EPISODIC_5"/>
				<offset 	 x="0.55" y="0.0" z="0.08"/>
				<rotoffset x="0.0"	y="0.0" z="0.0"/>
			</projectile>
		</data>

		<assets model="w_e2_glauncher">
			<anim group="gun@rifle"/>

			<!--	<effects> -->
				<!--	<muzzle fx="muz_grenade_launcher"/> -->
			<!--	</effects> -->
		</assets>
	</weapon>

Have fun!