The KC-17's S-tier status in Season 10 is specifically tied to its BS+ ammo. Without that ammo variant unlocked, it drops to the top of A tier instead — still strong, just not quite the same gun.
## AK-12: the biggest faller on this list  Fulcrum's number-one pick in Season 9 was the AK-12, called "hands down the best AR in the game" at the time, built around faster movement and faster ADS for a speed-focused meta. This is the pick that's changed the most: a Season 10 cross-class tier list places the AK-12 in the lower half of B tier, describing it as a mediocre gun that only received a minor limb-damage buff this season, while also becoming an expensive seasonal-quest item with little payoff for the cost. If you're coming to this guide expecting the AK-12 to still be the top AR, it isn't anymore — the KC-17 and several other guns have moved ahead of it. ## MCX LT: still solid, but no longer a top-tier pick  Ranked number two by Fulcrum for near-zero recoil and ease of use across any playstyle, the MCX LT has settled into a different role by Season 10: a Season 10 tier list places it as a solid mid-tier ("B tier") pick specifically because it's cheap and flexible, explicitly recommending the K437 instead if you want something stronger for a similar playstyle. It hasn't gotten worse in absolute terms — it's just been passed by newer and more specialized guns. ## MK4 and AR-57: still relevant, with caveats  Fulcrum's number-four pick is actually an SMG, not an AR — the video itself acknowledges the MK4 doesn't belong on an "assault rifle" list but includes it anyway because it out-performs most ARs at short-to-medium range in a movement-heavy meta. A Season 10 tier list agrees it's still good, placing it at the bottom of A tier: a unique SMG with real variability, best run on burst fire rather than a full-auto barrel.  The AR-57, ranked fifth by Fulcrum and described as a high-fire-rate SMG hybrid that melts short-to-mid-range targets (at the cost of a slow reload), also holds up reasonably well: a Season 10 tier list places it at the top of A tier or the bottom of S tier, with its penetration against top-tier armor as the only real weakness holding it back from a clean S-tier spot. ## What actually changed between these two seasons The pattern across both seasons is consistent even where individual gun rankings moved: low recoil and forgiving handling are still what separates a top pick from a mid-tier one, and Fulcrum's Season 9 framing (fast fights, low TTK, movement-heavy meta) still describes Season 10's meta reasonably well, even though the specific gun rankings built on that framing have partly shifted underneath it. ## How this guide was fact-checked Every Season 9 ranking, description and build detail in this guide is read directly from Fulcrum's top-five AR video (17:48, published 2026-05-01) and the Gunsmith attachment screens captured from its gameplay footage. Every Season 10 comparison point is read from this catalogue's own Season 10 (Meltdown) cross-class gun tier list guide, sourced from a separate, more recent video (published 2026-07-06) — exactly the cross-check this guide's own content planning called for before publishing a pre-Meltdown ranking as current advice. ## What this guide doesn't answer This guide doesn't give a current, from-scratch Season 10 assault-rifle-only ranking — for that, see this catalogue's Season 10 gun tier list guide, which covers the full cross-class picture including the CI-19, M7 and M14 (none of which appeared on this Season 9 AR-specific list at all). It also doesn't cover the RM277, a newer AR that a separate deep-dive video from another creator covers in more detail; this guide sticks to cross-checking the five weapons Fulcrum's original video actually covered rather than adding weapons neither source discussed together. Attachment names and calibration percentages are read from Season 9 footage and may not reflect Season 10's exact numbers if a weapon received attachment-level changes rather than just a tier shift.