Burris FastFire® 4 — Red Dot Reflex Sight

Item #: 300259 | Battery: 1× CR1632 (top load)

Tech Note — Astigmatism & “blurry” dots: Many shooters with uncorrected astigmatism or dry eyes see a starburst/comet-shaped dot. That’s an eye effect, not a defective optic. Quick checks: (1) view the dot through a phone camera (should look crisp); (2) lower brightness; (3) smaller dot reticle can help.
Training tip to “find the dot” (handguns): bring the sight close to your eye to acquire the dot, then press out slowly while keeping it centered; repeat until presentation is automatic.
Mounting gotcha: if you see a tiny glow from the emitter low in the field of view but no dot on the window, the sight is likely mounted backward—flip it.
Emitter cleanliness: a smudge/oil/dust on the small emitter lens can blur the dot. Blow off dust, use a soft brush, then (only if needed) a single drop of lens cleaner on microfiber. Avoid harsh solvents and don’t touch the LED.
Battery cap tool: FastFire 4 includes a small combination screwdriver for the battery cap. If it’s not available, use a properly fitting flat-head from a hardware store. Snug only—don’t overtighten.

1) Itemized Components (Product Map)

Item #	Component	What it does
1	Reticle Brightness Button	Powers on/off; cycles Auto → Low → Medium → High (hold 2s to power off).
2	Reticle Select Button	Toggles the four reticle patterns.
3	Elevation Screw (top)	Zeroing adjustment; reference tick marks.
4	Windage Screw (right)	Zeroing adjustment; has limit stops.
5	Sight Window / Lens	Projects the aiming dot; parallax-free, true 1×.
6	Brightness Sensor (front)	Drives auto-brightness; keep unobstructed/clean.
7	Top Battery Cap	Holds 1× CR1632 (positive up).

2) Package Contents & Specs

Included	Specifications
2× #6-48 Torx® screws, Torx wrench, protective cover, 1× CR1632 battery, Weaver/Picatinny-style mount, hex wrench, adjustment/battery-cover screwdriver, user guide.	Magnification 1.07×; window 29×18.75 mm (1.14″×0.73″); Elevation range 90 MOA; Windage 90 MOA; recoil resistance 1000 G; Operating temp −10 °F to +130 °F; weight ~1.06 oz (sight only).

3) Mounting (Plates, Orientation, Torque)

Topic	Guidance
Plates / Bases	Most rifles/carbines & some handguns use the included Picatinny/Weaver plate; other firearms use model-specific plates (see Burris mount finder).
Picatinny / Weaver	Place cross-screw in a rail slot; verify clamp edges fully engage. Maintain light forward pressure toward the muzzle and tighten the clamp nut to ≈20 in-lb.
Orientation Check	Window faces the target. A tiny glow low in the view with no dot on the glass usually means the sight is mounted backward.

4) Power, Brightness & Reticles

Power/brightness: On with either control button. Modes: Auto (sensor-controlled), then Low → Medium → High with each press. Hold 2 s to power Off. Low-battery warning: dot blinks twice every ~5 s (≈4 hours remaining).
Reticle options (toggle): 3 MOA dot; 11 MOA dot; 11 MOA dot with circle; 3 MOA dot + circle & “wings”.
Battery install: Top-load CR1632, positive up; keep contacts clean and don’t overtighten the cap.

5) Zeroing

Adjusters: Elevation on top; windage on right. Use the included combo tool. Tick marks are references (not calibrated clicks).
End-stop behavior: Windage has hard stops; if you drive into a stop it can momentarily lock the other axis—back off a few ticks and re-center.

6) Weather Shield (Enclosed Mode)

Slide the shield over the top and secure the two rear screws with the provided hex wrench. Do not overtighten. The shield improves clarity in rain/snow and stays attached even on pistol slides.

7) Environmental & Care

Water-proof; survives rain/snow and accidental submersion. After salt/dirty water exposure, rinse with distilled water and dry.
Clean optics with blower/soft brush first; then lens tissue/solution if needed.

8) Quick Specs (Reference)

Spec	Value
Magnification	1.07× (true 1× use)
Window	29 × 18.75 mm (1.14″ × 0.73″)
Adjustment Range	Elevation 90 MOA / Windage 90 MOA
Reticles	Four selectable (3 MOA, 11 MOA, 11 MOA+Circle, 3 MOA+Circle+Wings)
Battery	1× CR1632 (top load)
Operating Temp	−10 °F to +130 °F (−25 °C to +55 °C)
Weight	≈1.06 oz (sight only)

User Guide (PDF): FastFire 4 User Guide
Product Page: FastFire 4 — Item # 300259

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