Red dots and scopes on a used gel blaster: what the optic is actually worth
Quick Answer: Treat a sight on a used blaster as a separate item with its own price. RedSpearโs sales give the real numbers: an EoTech-style holo sold for $70, and a branded holo listed at $89 sold for $75 after 115 days. So a bundled sight is worth tens of dollars, not hundreds, unless itโs a named, working brand. Test it in person: switch it on, check the adjustments move, and nudge it to see if it shifts on the rail. And look at the rail slots. Square-bottomed slots at even spacing are Picatinny, and a mount off that rail fits almost anything.
I run a holo sight on both my main blasters, the MK18 and the N4. For indoor CQB, a holo or red dot suits the job: both eyes open, dot on target fast, shapes moving three metres away. So Iโm not going to tell you optics are a waste.
What I will tell you is that โcomes with red dotโ in a listing is usually priced as if the sight is worth far more than anyone will actually pay for it.
What sights actually sell for
RedSpearโs own sales of sights and lights sold on their own:
EoTech-style holo red dot: $70, sold in 28 days.
MG UH1 Gen2 holo sight: listed at $89, sold for $75 after 115 days.
DBAL-style laser and light unit: $59, after 104 days.
Thatโs the honest range for most gel blaster optics on the used market: tens of dollars, and slow. So when a listing is $50 dearer because of the sight on top, that sight has to be a named brand in good working order to justify it.
Price the optic separately
A barrel or hop-up is part of the blaster. A sight comes off in thirty seconds and has its own market, just like a battery or a mag. One message sorts it out: โHappy with your price on the blaster. What would you want for it without the sight?โ It isnโt a lowball. It puts the sightโs value in the open (making a fair offer).
Named brand and model: you can look up what it costs new and work back. Worth real money if it works.
Replica markings, no brand: a cheap optic, because thatโs what the next buyer will treat it as.
Unmarked, no caps: fine for your first game. Donโt add it to the price.
Two checks in person
Switch it on and look through it, in daylight, and turn the brightness and both adjustment turrets. They should click and hold.
Nudge it sideways with your thumb. If it moves on the rail, the mount or screws are done. A sight that wonโt hold zero is one youโll ignore all game. Same pass as the 10-minute inspection.
๐ฃ The rail decides whether the sight is yours or stuck on that blaster
โ20mm railโ is only half the story.
People say โ20mm railโ as if that settles it. Thatโs the outside width. What decides whether a mount locks up is the slots cut across the top, and there are two standards.
Picatinny (MIL-STD-1913) cuts square-bottomed slots 5.23mm wide, spaced 10.01mm apart. The older Weaver pattern uses narrower, rounded slots without a fixed spacing. The fit only runs one way: a Weaver mount fits a Picatinny rail, but a Picatinny mount may not fit a Weaver rail, because its locking bar is too wide for the slot.
The check takes ten seconds, from a photo: square-bottomed slots at even spacing mean Picatinny, and the sight will go almost anywhere. Rounded or uneven slots mean Weaver, so assume the sight stays with that blaster and price it that way.
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What a sight actually does for you
Indoors, a red dot or holo earns its place. At CQB distances, fast target pick-up with both eyes open is most of the game.
Magnified scopes mostly donโt. Gel is slow and drops quickly, so at the ranges a gel blaster actually reaches, magnification mostly gives you a narrower view of the same target (sniper and DMR guide).
A sight canโt fix grouping. Gels landing all over the place is the barrel, hop-up and gel (fixing flyers).
Eye protection comes first. On a first blaster, full-seal eye protection is the purchase that matters (first game loadout).
Frequently asked questions
How much is a used red dot worth?
On RedSpear, sights sold on their own went for $70โ$75, and slowly: one took 115 days. A named, working brand is worth more. An unbranded dot adds little to a blasterโs price.
Picatinny or Weaver: how do I tell?
Picatinny slots are square-bottomed, 5.23mm wide and evenly spaced at 10.01mm. Weaver slots are narrower, rounded and not evenly spaced. Weaver mounts fit Picatinny rails, but not always the other way round.
Is a scope worth it on a gel blaster?
Usually not. Gel is slow and drops quickly, so magnification adds little at gel blaster ranges. A red dot or holo is the better choice for most games.
Should I sell my sight with the blaster or separately?
If itโs worth more than an unbranded dot, name the brand and model in the listing. If itโs better than the blaster, list it separately: a good sight sells to someone who already has a blaster.
Sources
- Wikipedia - Picatinny rail (MIL-STD-1913 dimensions, Weaver compatibility)
- RedSpear Armory Shopify sales data, MayโOctober 2026 (used items, with days from listing to sale)
Last checked: 31 October 2026.
Looking for a sight, or selling one?
Optics and mounts turn up in used parts and accessories. Selling? List free and name the brand, model and mount.
Read next: Rails, stocks and grips ยท Valuing a whole kit ยท A night at Blacksite
Written by Patrick Amadeu
Founder of RedSpear Armory and a critical care paramedic since 1989. Iโve played indoor at Blacksite and the former GelSoft Yatala, and outdoor at Donnybrook, Kooralbyn and Bundaberg. RedSpear exists because my first rifleโs gearbox died four days after the shopโs warranty ran out. More about me
RedSpear Armory โ Queensland's dedicated marketplace for used gel blasters. Browse listings, sell your gear, and connect with the local QLD community at redspeararmory.com.au.