Here’s what most buyers never consider: a shooting bag gets mated to two objects at once. The first — and the one that decides stability — is the surface under it. Round, square, thin, or thick, the shape doesn’t matter. What matters is whether the bag carries enough weight to stabilize itself on that surface — a bag too light to plant sacrifices stability on the prop. The second is the rifle. A competition rifle at 20-plus pounds has no trouble pressing a shooting channel into the top of a Fortune Cookie — a stable place for the rifle to rest, and to move in under recoil. Every fill below is really one question: how much weight are you giving the bag to plant itself with — and what makes up the difference when you give some back. We fill every bag before it ships, so this is the menu exactly as it runs through our own scales.
Sand Fill — the pro default
Maximum stability, because stability starts with weight — the bag plants itself on the prop before the rifle ever touches it. The larger grain rolls out of the channel with less effort, so building a fore-end channel is fast and forgiving. If the bag lives in a truck or on a match cart and weight is free, run sand. (MiniX: 10.8 lb.)
Glass Fill — same weight, different feel
Identical weight to sand. The finer media settles faster and packs denser, so you’re more deliberate about how much force builds the channel — sand rolls and evacuates faster with less effort. Neither is “better.” It’s feel, and shooters split on it. (MiniX: 10.8 lb.)
Hybrid Fill — the 20% solution
A blended fill that sheds 20% of the weight of the heavy fills without giving up stability. The trick is maximum conformity: the blend molds harder to both objects the bag mates with — the surface under it and the shooting channel the rifle presses into the top — so conformity holds what weight used to. Engineered to stay blended; the two media never separate no matter how the bag rides. The pick when the bag has to travel and the stability can’t. (MiniX: 8.6 lb.)
Poly Fill — the do-most middle
For when a fraction of the weight is necessary. In the two-object frame: the bag-to-prop marriage isn’t as stable — a lighter bag doesn’t plant as hard — but the rifle channel stays solid. And because poly holds its shape when squeezed, it’s the rear-bag pick: squeeze to elevation, it stays put. (MiniX: 4.25 lb.)
SpexLite 5125 Light Weight Fill — ounces, on purpose
The lightest fill of all — for when extreme mobility is the mission: hunting, land navigation, miles between positions. In the two-object frame it gives up the most plant on the prop, and it matters least here: the accuracy standard changes when the target is a vital zone, not a match plate measured in inches. A MiniX drops to 1.5 lb; a Micro runs half a pound — a bag you forget you’re carrying until you need it.
Weights across the line: Micro 0.5–3.2 lb · MicroX 0.7–4.8 · Mini 1.0–7.8 · MiniX 1.5–10.8 · Max 2.2–16 · MaxX 2.9–20.
Change your mind later
Every Fortune Cookie can be ordered with the SwapSpout (+$15) — swap between fills in minutes instead of committing to one. Match sand in September, SpexLite in November: swap fills, not bags. Spare fills sold separately, measured to your bag. Older bag? Our repair bench retrofits the spout for $25 plus shipping both ways.
Not sure which bag the fill goes in?
Shooters' notes from College Station
Fill science, match-prep checklists — and limited runs sell to the list first.