McMillan TAC-300
- Category
- Sniper Rifle
- Barrel
- 660 mm
- Weight, empty
- 5.44 kg
- Introduced
- 2006
About
What it is, and why it matters
The McMillan TAC-300 is a purpose-built tactical precision bolt-action sniper rifle chambered in .300 Winchester Magnum, designed for long-range military and law enforcement engagements. It is built on McMillan's proprietary G31 receiver mated to a 26-inch heavy, match-grade free-floating stainless steel barrel with a 1:10-inch twist and a threaded muzzle for suppressor or muzzle brake attachment. The rifle is bedded in the McMillan A5 tactical fiberglass stock, which incorporates an integral adjustable cheek piece, a length-of-pull spacer system, and flush-mount sling swivel cups. An adjustable trigger set at approximately three pounds and an NP3-coated bolt contribute to consistent sub-MOA accuracy. The .300 Winchester Magnum chambering extends effective reach well beyond that of the .308 Winchester TAC-308, making the TAC-300 a favored choice for extended-range precision work.
McMillan earned its reputation in the sniping world with the TAC-50, which set the record for the longest confirmed combat kill in Afghanistan. The TAC-300 applies that same tactical bloodline to the hard-hitting .300 Winchester Magnum, bridging the gap between the .308-class TAC-308 and the anti-materiel TAC-50.
Uses McMillan's G31 short-magnum action with an NP3-coated bolt. Muzzle threaded 5/8x24. Cerakote finish offered in black, tan, and olive drab. MSRP around $6,000.
Specification
Everything measured
IdentityWhat it is, who built it and when.
- Manufacturer
- McMillan Firearms
- Category
- Sniper Rifle
- Country
- United States
- Status
- In production
- Produced
- 2006
DimensionsAs issued, without a magazine or an optic.
- Barrel
- 660 mm
- Overall length
- 1181 mm
- Weight, empty
- 5.44 kg
- Weight, loaded
- 5.67 kg
ActionHow it cycles, what trips it, and what feeds it.
- Action
- Bolt action
- Firing mechanism
- Striker fired
- Trigger
- Single stage
- Trigger pull
- 13.3 N
- Capacity
- 5
- Magazine
- Detachable box
MaterialsEach swatch is the material itself, not a colour chosen to stand for it.
- Frame
- Steel
- Barrel
- Stainless steel
- Stock
- Fiberglass
- Finish
- Cerakote
BallisticsFrom the service cartridge, not a handload.
- Muzzle velocity
- 900 m/s
- Muzzle energy
- 4720 J
- Effective range
- 1100 m
- Maximum range
- 4300 m
Trajectory
What the round does downrange
Solved from the muzzle figures and the bullet. The dashed rule is the effective range on the record, and the crosses are the steps the solver returned.
No load solved for this record yetThe flight path is computed from a cartridge and a bullet. This record has no ammunition filed against its chambering, so there is nothing to solve.
Features
What it has
What the record lists as fitted, drawn from the catalogue.
Free floating barrel
Threaded barrel
Adjustable cheek piece
Match grade barrel
Adjustable trigger- Flush mount swivel cups
Spacer system length of pull
Standing
How it compares
Each figure against the firearms of the same type and cartridge that record it, or of the same type where that cartridge has too few. Positions are read to the nearest tenth.
| Measurement | This firearm | Median | Position |
|---|---|---|---|
| Empty weightAmong 430 sniper rifles | 5.44 kg | 5.40 kg | Near the median |
| Overall lengthAmong 429 sniper rifles | 1181 mm | 1150 mm | Longer than about 60% |
| Barrel lengthAmong 434 sniper rifles | 660 mm | 620 mm | Longer than about 60% |
| Magazine capacityAmong 434 sniper rifles | 5 | 6 | Holds fewer rounds than about 70% |
Answers
Questions about the McMillan TAC-300
How much does the McMillan TAC-300 weigh?
The McMillan TAC-300 weighs 5.44 kg (12.00 lb) empty and 5.67 kg (12.50 lb) loaded.
What caliber is the McMillan TAC-300?
The McMillan TAC-300 is chambered in .300 Winchester Magnum.
How many rounds does the McMillan TAC-300 hold?
The McMillan TAC-300 holds 5 rounds, fed from a detachable box magazine.
How long is the McMillan TAC-300?
The McMillan TAC-300 is 1181 mm (46.5 in) long overall, with a 660 mm (26.0 in) barrel.
Who makes the McMillan TAC-300?
The McMillan TAC-300 is made by McMillan Firearms (United States).
When was the McMillan TAC-300 introduced?
The McMillan TAC-300 was introduced in 2006.
How does the McMillan TAC-300 operate?
The McMillan TAC-300 uses a bolt action, and its firing mechanism is striker fired.
Compatibility
Which parts fit this firearm
Studio
Every part that mounts on this, resolved
Not a list the maker typed out: the answer comes from the mounts this firearm exposes and the interface each part needs, so it stays right when either one changes.
- Every part that mounts on any firearm in the catalogue
- Interface standards, platforms and fit overrides
- The same answers through the API and the MCP server
Requires a signed-in GunSpec account on the Studio plan. The answer is computed per part, so it is not part of the public record.
Provenance
What the record holds
Every figure above was taken from one of these pages. The confidence reflects how much of the record came from a page a claim can be checked against.
Provenance
Confidence in this record
75%
Stockists
Where to buy
Offers link straight to the shop. GunSpec never takes the order.
No shop has listed this firearm yet
Stock and prices come from the shops themselves. If you sell this firearm, you can list it and it appears here.
List a firearmMCP
Ask an assistant about it
The same record, reached the way a person asks for it rather than the way a program does.
Ask GunSpec
Works with
Point an MCP client at GunSpec and it answers from the catalogue rather than from memory. A free key covers the read tools.
API
The call that returns this record
The same fields, in the same units, from the same endpoint the page reads.
curl --request GET \ --url 'https://api.gunspec.io/v1/firearms/mcmillan-tac-300' \ --header 'X-API-Key: your_key'{ "id": "mcmillan-tac-300", "name": "McMillan TAC-300", "manufacturer": { "id": "mcmillan", "name": "McMillan Firearms", "countryCode": "US", "foundedYear": 2007, "website": "https://www.mcmillanfirearms.com", "logoUrl": null, "description": "US-based tactical rifle manufacturer founded in 2007 by Gale and Ryan McMillan. Known for precision bolt-action rifles and the world-renowned McMillan Tac-50. Has legacy in stock manufacturing dating back to 1973. Purchased by Strategic Armory Corps in 2013.", "status": "active", "defunctYear": null, "stateOwned": null, "makesFirearms": true, "parentId": null, "predecessorId": null, "createdAt": "2026-02-11 23:44:38", "updatedAt": "2026-02-18 03:40:45", "version": "2cc15a49fc15c948861751ba2f5e1320fa33771b0a3e726a11923e32a1335627" }, "category": { "id": "sniper-rifle", "name": "Sniper Rifle", "description": "Precision rifles optimized for long-range accuracy" }, "country_of_origin": "US", "year_introduced": 2006, "barrel_length_mm": 660, "weight_empty_g": 5443, "action_type": "bolt_action"}