Do the ranger spells like lightning arrow work in combination with volley

Yes!

Are you speaking of the hunter subclass feature volley? 

At level 11 the hunter ranger is a master of martial AoE damage. Stacking the volley ability with the lightning arrow spell when there are 3 or more enemies within 10 to 20 feet of one another is massive! 

It doesn't work to create an uber lightning arrow volley

Volley:

You can use your action to make a ranged attack against any number of creatures within 10 feet of a point you can see within your weapon’s range. You must have ammunition for each target, as normal, and you make a separate attack roll for each target.

Lightning Arrow:

The next time you make a ranged weapon attack during the spell’s duration, the weapon’s ammunition, or the weapon itself if it’s a thrown weapon, transforms into a bolt of lightning. Make the attack roll as normal. The target takes 4d8 lightning damage on a hit, or half as much damage on a miss, instead of the weapon’s normal damage

I'm pretty sure this means that the first attack you make as part of the volley expends the magic from the lightning arrow, and then the rest are made as normal. Can you still get some good AOE damage out of this, for sure, but it's not going to hit multiple creatures with lightning and then create several triggers of the arc. Maybe that wasn't what either of you meant. If it was just a matter of being able to fire a lightning arrow as one part of a volley, then yes, that works. Not sure, OP is vague.

I don't think it works with conjure volley either

Conjure Volley

You fire a piece of nonmagical ammunition from a ranged weapon or throw a nonmagical weapon into the air and choose a point within range. Hundreds of duplicates of the ammunition or weapon fall in a volley from above and then disappear. Each creature in a 40-foot-radius. 20-foot-high cylinder centered on that point must make a Dexterity saving throw. A creature takes 8d8 damage on a failed save, or half as much damage on a successful one.

Firing the ammunition or throwing the weapon is not an attack action when casting this spell. It's more akin to a somatic component using the material one. If you cast this spell while concentrating on Lightning Arrow, then LA won't trigger and will still be there for the next time you make a ranged weapon attack.

One thing you could do for your aoe burst is preload a lighting arrow during the previous turn, then next turn do your volley with the intial strike being a lightning arrow, interrupt the attack to cast lightning arrow again and then continue attacking.

Good if you have prep time before combat or if you want to compete the single round damage highscore within your party.

That's a good point Wannyboy and a sweet tactic if you have the time to ambush and the spell slots to spare. A sweet way to nuke some enemies but it comes at a high cost

It's about 87 damage to 3 enemies in one turn (plus the last bit of the turn before). That is pretty great damage for a couple of level 3 spell slots!

That's only if you have 20 dex, the enemies fail all of their saves and you hit all of your attacks. Definitely closer to 60ish average damage. Is it better than two castings of conjure animals? haha. Can't seem to get away from that spell.

LOL!  I love conjure  animals!

I imagine most rangers will have a +5 modifier to dexterity by level 11, but that does assume hitting all attacks because I did not factor in to hit ratios. I did factor in a 50% successful saving throw for the spell damage however.

And yes, I would be more likely to cast conjure animals than lightning arrow most of the time. So much fun. 

Pretty sure I figured out what we did differently. I didn't factor in sharpshooter. oops. Should have since that's a given on an archer. Yeah that's definitely good damage. I would probably save this tactic for when you can ambush your enemies and cast the first lightning arrow in hiding. Otherwise it's barely different than spreading out the lightning arrows between two rounds, at which point I'd rather use a single action to conjure animals the first turn and then start attacking afterwards. You'll generally get far more out of that sequence over 3+ turns of combat IMO (and only spend on 3rd level slot)

I didn’t use sharp shooter, but I did use only average damage. Let’s see...with 3 targets within the different ranges, of the spell and ability.  The 2d8 damages can save for half, 40% of the time as per the video below, but the rest is based on a to-hit chance, normally of 60% but we’ll make it 70% for the archery fighting style. The number I posted above was just average assuming all hit with half save 50% of the time for the saving throw damage.

Lightning Arrow 1: (3d8 + 2d8 + 2d8)

Lightning Arrow 2: (3d8 + 2d8 + 2d8)

Volley Attack: ((1d8 + 5)*3 + 1d8)

So just straight assumes hit average damage with 50% save for half would be 87 average damage, while factoring in to-hit chance it would be 63.6 damage.

Ill use this fella’s video: https://youtu.be/zg0bAl1WPGQ

A paladin using a great sword and 2 level 3 spell slot smites would do 42.6 with the to-hit calculations. 

I didn’t factor in chance for critical damage, either time.

I would love to know if war magic feature would trigger hunter ranger’s volley action  as a bonus action since it is making a weapon attack? If so 7 lvls eldritch knight fighter / 11 lvls hunter ranger/ 2 lvls fiend or genie warlock could be a very strong multiclass. 

Warlock to get invocations agonizing blast and repelling blast.     

then make attack action with eldritch blast which triggers war magic to cast volley action