I need tips for status gunning

Well, it's sad that I've only gathered the required resources for the most multiplayer-friendly playstyle now that the servers are going down. But, well, what can I do? I've always wanted to go status gunning because everyone loves status gunners.

But I need tips to become a better gunner. I can't help but feel dread at the thought of encountering haruno one day and having him/her bash me in-game for sucking.

So, these are my specs:

Frame: Light Bowgun
Barrel: Light Bowgun
Stock: Chaos Wing

(That gives me 4 Para Lvl 2, 2 Para Lvl 1, 2 Sleep Lvl 1, 1 Sleep Lvl 2, 3 Poison Lvl 1 and 3 Exhaust S shots.)

And I have the following skills:

• Recoil Down +3
  
• Defense Up (S)
  
• Sneak
  
• Bombardier
  
• Trap Master

The strategy depends on the monster, but it's most effective on flying monsters, because then it consists of Pitfall Trap -> Flash Bomb -> Para -> KO -> repeat.

The problems I've been having with this one strategy are:

• It's extremely hard to KO a monster alone. Most of them require, I don't know, 15 Exhaust shots or more to be KO'd. This is only ensured to work if there is a hammerer around, and even then
  
• A good hammerer will get a KO while the monster is trapped. This is all good, but if one wants the tail cut, there might be not enough momentum.
  
• Sneak is great! It really does work wonders overall. The problem is that if I fail to KO the monster while it's paralyzed, I'll never get the chance again, since it will almost never face me and it's harder to aim like that.

It's even worse with monsters that don't fly. I don't have a strong enough strategy that immobilizes the monster for more than one minute. Deviljho gets hungry often, so it's not much of a problem since I can basically trap -> para it forever and not even move mch around. But it's not very good otherwise.

Is Load Up necessary? What other skills or strategies could I use? And why in the world do I keep running out of ammo even though I can carry any elemental shot?

Okay...for status gunning you rarely need recoil+3 skill as +2 will be sufficiant for most things.
Id use a different gun though, seeing as that combo is pretty weak in itself, sure status is nice but damage is nice to have as insurance. Also seeing as your gun has no shield I highly recommend evade seeing as you cant block and your defence is very low.
I use stuff like these when I support:
http://mhtri.comeze.com/armor.html?0_1v_1S.1R_1h.1S.1R_1h_1R.1R_p.1F.1S
Its not amazing, but fairly easy to make and served me well for many HR's and still use it today.

As for gun I either use:
Rathling+ frame,Chaos Wing and peco/needler barrel (needler gives pierce shots and wyv fire lv 1)
This setup gives (with Load up) 3 exhaust, 3 lv1 paras, 3 Lv2 paras, 2 shots of Lv2 sleep, 3 recov lv2 shots and natural low recoil. It can also hold Dragon S and wyv fire, which is nice to have with its good attk power.

or Bari frame, Chaos wing and needler.
Standard Sleepbombing setup holding (with load up): 5 pierce lv 2's (boosted by +20% natural affinity), 3 Wyv fire Lv1's, 3 sleep lv 1's, 4 sleep lv 2's, 3 recov shot lv 2's, 3 lv 2 paras and 3 exhaust.

Question 1: Load is is not needed but it help alot when you gun, you will be suprised by how useful it is.
Question 2: Carry more than just elemental shots, carry all the things needed to combine into that ammo type (like fire herbs+huskberry) as well as a few pierce shots. You shouldnt run out if you pack properly.