Stihl MS 291 vs MS 311: When You Need a Little More Saw

Every ladder has a rung where “a little more” is the whole sales pitch, and in Stihl’s lineup that rung is the MS 311. It’s not a professional saw, nobody at the dealership will tell you it is, but if the MS 291 leaves you wanting a longer bar and more pull in big wood, this is where you land before pro prices start. 59.0 cc, 4.2 brake horsepower, and bar options from 16″ all the way to 25″ and for the first time climbing this wall, the chain system, the oiler, and the starting hardware all change at once. Let’s take it from the top.

The Step Up 59 cc, 4.2 bhp, Up to a 25″ Bar

The numbers first: the MS 291 runs 55.5 cc making 3.8 bhp at 12.4 lb. The MS 311 runs 59.0 cc making 4.2 bhp at 13.8 lb. Here’s the perspective that stops people: 4.2 bhp is more raw power than the professional MS 261 makes. The 311 simply carries it in a 13.8 lb farm-saw body instead of a 10.8 lb magnesium one. Power-to-weight barely moves against the 291 (0.31 vs 0.30 bhp/lb), so you’re not buying a livelier saw but you’re buying absolute capability: the grunt to pull a longer bar through bigger wood. And the bar menu is the tell. The 291 tops out at 20″; the 311 sells in 16″, 18″, 20″, and 25″ configurations. If your property has trees that make a 20″ bar look short, this is the first saw on the wall built for them. Your floor observation is the right summary: this is the sweet spot if you need a longer bar and more power than the previous models and you don’t need a pro saw’s price to get it.

Three Firsts on This Ladder Decomp, Adjustable Oiler, Big-Bore Manners

Climbing from the 291, the 311 picks up equipment that until now lived only on the pro side of this series. It gets a decompression valve, press it before pulling and it bleeds cylinder pressure so a 59 cc engine starts without fighting you. (No primer bulb, though, and no Easy2Start — this is still a firm-pull farm saw; the decomp just makes the firm pull civilized.) It gets an adjustable oiler, and on this saw that’s not a luxury: a 16″ bar and a 25″ bar need very different oil flow, and a fixed oiler can’t serve both. Dial it up for the long bar in dry hardwood, back down for the short bar, and stop guessing. The rest of the equipment reads like the 291 you already know: translucent fuel tank, toolless tank caps, three-screw top engine shroud, two bar nuts on the sprocket cover, and a fleece air filter that takes the HD2 upgrade — same cheap pro trick as the 271 and 291.

The Chain System Changes Again Goodbye .325, Hello 3/8

If you’ve followed this series, you’ve watched the chain spec shift at nearly every rung and the 311 makes the biggest jump yet: it leaves .325″ pitch behind entirely for full 3/8″ pitch at .050″ gauge. Bigger cutters, more bite per pass, built for the displacement pulling it. The factory combos off Stihl’s own configurator: 18″ = 33 RS3 66 (66 drive links), 20″ = 33 RS3 72 or 33 RM3 72, 25″ = 33 RS3 84. And note those letters, most 311 combos ship RS3 full-chisel chain, a first in this ladder. Full chisel cuts noticeably faster than the RM3 semi-chisel on the 271/291; it also dulls faster the moment you touch dirt or bark grit. Nothing from your .325″ saws carries over here, not the chains, not the bars, and not even the file: full 3/8″ Stihl chain sharpens with a 13/64″ file, not the 3/16″ you’ve been using.

Side-by-Side Spec Table

Specs per Stihl USA published data; weights are Stihl’s “device weight without refuelling.”

The Verdict From Behind the Counter

Stay with the MS 291 if a 20″ bar covers your biggest regular wood. It’s lighter, cheaper, and gives up nothing in features you’ll actually miss. Step up to the MS 311 if your trees have outgrown 20 inches, if you’re pulling a long bar through hardwood and want the oiler dialed to match, or if you simply want the most absolute power available before the price jumps to the professional tier because that’s precisely what this saw is: pro-level grunt in a farm-saw body at a farm-saw price. The honest asterisk from behind the counter: at 13.8 lb plus a long bar, this is a heavy tool, and if you’re planning daily hours with it, the power-to-weight math says look at the pro saws before you commit — your forearms will cast the deciding vote. For the rancher or firewood cutter who meets a genuinely big tree a few times a month? The 311 is the sweet spot, exactly like the man behind the parts counter told you.

Frequently Asked Questions