Hello there,

As per Wiki:

• Kuva Twin Stubbas: Akimbo variant; higher rate of fire and magazine capacity.
• These weapons have a max rank of 40. To obtain the maximum rank, the player must polarize the weapon five times, with each Forma increasing the maximum possible rank by 2 (similarly as the Paracesis).
• All Kuva weapons deal innate elemental damage in addition to physical damage. The amount of this damage is random, ranging from 25-60%, while the type of element is determined by the Progenitor Warframe, as per the table below:

According to the above, I added exactly 5 forma to this weapon, so we can obtain Mastery Points from it.

In this case, I recommend picking Magnetic as an elemental.

Some info about weapon:

• High fire rate
• High accuracy
• Large magazine
• Large max ammo capacity
• Slow reload speed
• Fairly low ammo economy
• Very noticeable recoil, which can throw off precision aiming (Stady Hands mod can reduce it)

If we consider the above we can create very powerful sidearms, but we need that Steady Hands mod on Exilus to reduce that huge recoil, here's the test results:

Enjoy, THeMooN85