Call of Duty: Modern Warfare 2 ups the ante when it comes to gun customisation with more attachments than ever and a wealth of weaponry to try out.

One completely new feature in its Gunsmith system, though, is weapon tuning - it's a little complicated, though. We've got all the details you need on weapon tuning, right here.

How does weapon tuning work in MW2?

Weapon tuning lets you further edit the attributes of an attachment that you add to your gun by dialling up a positive addition and accepting a negative one.

So, for example, if you add an underbarrel grip that makes for more stable recoil, but slower aim down sights time, you can tune this for a slightly different effect.

You could reduce how much stability it gives you, while making it quicker to aim down your sights. Or, you could do the reverse, and make it more stable but even slower.

This sort of give-and-take is at the heart of weapon tuning, and in most cases you have two such variables per attachment, edited by moving sliders.

In the images below, you can see one such attachment in its default state on the M4, and with the sliders maxed out to show a different graph for its performance.

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Above is the default readout.

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While the second image above shows it with tuning completed (to an extreme).

How do you unlock weapon tuning in MW2?

In order to unlock weapon tuning on a given gun, you need to complete the levelling process for that gun.

How many levels that requires you to unlock varies from weapon to weapon - for the M4 assault rifle, there are 20 weapon levels to work through, but some guns have almost double this number, with others totting up fewer.

How does weapon tuning work in Call of Duty Modern Warfare 2? How to unlock MW2 attachment tuning photo 2
Pocket-lint

This means that the amount of work it takes to unlock weapon tuning for each gun varies a lot, which can be a little unhelpful.

Once you've unlocked tuning, you can access it for each attachment by finding the "Tuning" button above each attachment as you select it in Gunsmith.

Is weapon tuning worth it in MW2?

We're still only a short while into Modern Warfare 2's lifespan, so for now we don't really know how key weapon tuning is to making the best gun builds in the game, honestly.

When creators have had longer to dive into the stats behind each gun this may become clearer.

It'll also likely have a bigger impact on weapon builds aimed at Warzone 2.0, where the time to kill is a lot slower thanks to armour plating. This means that things like weapon stability and movement speed become a very different question.

For now, we wouldn't say you should concentrate on grinding every weapon to maximum level just for the sake of tuning it. If you don't like using it halfway through that process, tuning attachments is unlikely to completely reverse that situation.