Mk13 Mod 0 clone build: the SEAL .300 Win Mag, part by part

On 23 November 1993 the Navy cleared a 190 grain .300 Win Mag match load for its snipers. Gunsmiths at Naval Surface Warfare Center Crane, in Indiana, built the rifle to shoot it: a trued Remington 700 long action in a McMillan A2 stock, bedded on an L shaped lug Crane made itself.

The rifle became the Mk13 Mod 0, and the Mod 1 is its left handed twin. You can build a close copy today, but the Crane lug and the McCann MIRS rail turn up only on the used and collector market.

What a Mk13 Mod 0 clone copies

A Mk13 Mod 0 clone copies the McMillan stocked .300 Win Mag that NSWC Crane built for SEAL snipers before the Mod 5's AICS chassis replaced it in the mid 2000s.

Four parts give it away: a Remington 700 long action, a McMillan A2, the Crane L lug with its third action screw, and a McCann MIRS rail. Pick a year before you buy. The scope and rings changed between the 1990s rifles and 2005.

Three answers point you to a build.

Mk13 Mod 0 parts list: the issued part and what to buy

Here's every slot, what Crane issued, what you can buy and how strong the evidence is.

Parts from this guide that we stock, laid out overhead. Product photography is supplied by the listed merchants through their affiliate feeds.

Status is ours as of 27 September, and gone means you'll find the part only used.

Mk13 Mod 0 history: how Crane built the SEAL .300 Win Mag

Crane's armorers built these rifles for the SEAL teams, and we cover the Mk12 Mod 0 from the same Crane shop separately.

Why the Navy wanted a .300 Win Mag in 1993

The Navy's match rifle team and the SEALs wanted more reach than 7.62 NATO. A 1995 Defense Department photo, our cover image, still shows a SEAL Team Five sniper firing an "M-91 .308 caliber sniper rifle."

A 190 grain Sierra MatchKing load, later designated Mk 248 Mod 0 (DODIC A191), was cleared for sniper combat use on 23 November 1993. Crane's 2009 briefing gives it a published effective range of 1,200 yards, a figure for the cartridge rather than any rifle.

The Crane builder's account: about 300 rifles

Alan Brown, a former Crane gunsmith who built the rifles, told a collector that Crane made about 300 for Naval Special Warfare and fitted maybe 50 for suppressors. The collector relayed it on Sniper's Hide in 2017 and 2018, so it's one account, second hand.

By that account, rifles left Crane with a sandblasted stainless barrel, a blued receiver and a fixed 10x Leupold Mark 4 M1. Brown later said some left with 16x scopes.

The rifles went to Afghanistan and Iraq. For the 5.56 half of a SEAL sniper's kit, see the Mk12 Mod 1 carried alongside the .300s.

When the 700/300 became the Mk13 Mod 0

No dated Navy document naming the rifle has turned up. Most dope cards on surplus stocks read ".300wm" and only a few "Mk13," so a collector concludes the name came later.

Collectors cite a 2004 McCann rail order for "the new Mk 13 Mod 0/1" and a 2005 Mk13 Mod 0 repair standard, though neither original has surfaced. One veteran poster thought the name came in the mid to late 1990s.

By the collectors' dating, a Mk13 Mod 0 wears a MIRS rail and a 1990s build is a 700/300. We cover the rest of that era's gear in the Lone Survivor Mk12 build, SEAL sniper kit in 2005.

Chris Kyle's .300 Win Mag: what is documented

PrecisionRifleBlog notes that Chris Kyle's book never names the Mk13. We haven't read the book itself.

Kyle wrote that his early .300 Win Mags had McMillan stocks, customized barrels and Remington 700 actions. That fits a Mod 0 or a 700/300. His Ramadi platoon got new .300s with Accuracy International stocks in 2006.

Three labels you'll see online don't hold up. Wikipedia calls his rifle a Mod 1, but collectors define the Mod 1 as left handed, and nothing we reviewed says Kyle shot left handed.

PrecisionRifleBlog's Mod 4, with an NXS 8-32 and a KAC Mk11, rests on unnamed industry experts, and one collector's Mod 4 is a left handed suppressed rifle. Charlie's Custom Clones says he mostly used the Mod 5 and calls it an Accuracy International AW, yet the Mod 5 is a Remington or Stiller action in an AICS 2.0.

Collectors link Kyle to Mod 0 and Mod 3 rifles, but nothing they've posted settles which he carried.

The action: Remington 700 long action, bolt and trigger

A new Remington 700 long action gives you the receiver, bolt and trigger. It can't give you Crane's trueing or a 1990s serial.

Action: a blued Remington 700 long action, trued

Crane built on blued Remington 700 long actions with a magnum bolt face, trued before assembly. Collectors tie C and E prefix serials to the Mod 0 and G prefixes to the later Mod 2, 3 and 5. Stiller actions came later still, on late Mod 5s and the Mod 7.

We don't list Remington actions. MidwayUSA had the long magnum action, part number 27557, in stock at $599.99 on 27 September. Brownells lists that number as blued with the X-Mark Pro trigger, so confirm the finish before you order.

Bolt and extractor: factory, Sako style or M16

The extractor is the most argued detail on the rifle, so pick a period. A Scout forum list quoted on Sniper's Hide puts factory extractors on the early 700/300s and Dave Tubb's Sako style on many later Mk13s. The Crane builder advised against the Sako.

The AR15.COM Mod 5 guide calls an M16 style extractor a Crane step, though a shooter who saw Crane rifles in the early 1990s doubted it. We don't stock extractors. Brownells and Ammunition Depot had Badger's magnum M16 style extractor at $37.49 to $39.99.

Trigger: the factory Remington, tuned by Crane

Crane kept the factory Remington 700 trigger and tuned it, the builder said, after aftermarket triggers couldn't cope with dirt. The Walker trigger at 3.5 lb on a Clone Rifles Australia list is that factory design.

We list only aftermarket Remington 700 triggers, none right for a Mod 0, so there's no card here.

The McMillan A2 stock, Crane L lug and bottom metal

These three parts make the rifle a Mod 0, and they're the hardest to find.

Stock: McMillan A2 with adjustable saddle, grey or tan

The issued stock is a fiberglass McMillan A2 with a single knob adjustable saddle and a spacer butt. It's inletted for a right hand Remington 700 long action, the Crane L lug and BDL bottom metal. Early contract stocks were grey, later ones tan, and snipers painted many in the field.

Surplus originals came from a government disposal sale and never went back to McMillan, says the collector who sold about 155. McMillan has made limited reproductions since 26 October 2024, and its preorder page for a tan one was live on 27 September.

One comparison found the reproduction's inlet slightly forward, with no recess for the third screw's escutcheon. An A3 is close but wrong, and we don't list McMillan.

Recoil lug: the Crane L lug and its third action screw

Crane's L shaped lug takes a third action screw just ahead of the magazine well, so a screw there marks an original Crane inlet. A collector says the L lug appears only on the rifles before the Mk13 name and on the Mod 0, 1 and 3.

No store sells it. Collectors say Badger made a Mk 13 lug and that Red Bull Armory's reproduction is the straight Mod 5 and Mod 7 pattern. A surplus lot of 55 sold out in 2019. Some builders fit a standard lug and glue a dummy screw head into the third hole.

Bottom metal: Remington BDL hinged floorplate

The stock takes Remington BDL hinged floorplate bottom metal with an internal box, follower and spring. A 1999 Navy spec, as a collector quotes it, gives 3+1 rounds. The five round figures online come from the Mod 5's AI magazine.

We don't stock bottom metal, and no in stock listing in our feeds says BDL hinged floorplate, so check the pattern before you buy.

The Lilja barrel and muzzle

Your gunsmith does most of the work here.

Barrel: Lilja 26.5 inch, 1 in 10, Tactical taper

Collectors identify the Mod 0 barrel as Lilja's Tactical taper, 1.200 inches at the breech and 0.780 at the muzzle, cut 4 groove and 1:10 and finished at about 26.5 inches. Lilja says a military customer developed the taper but never names the Mk13.

Don't order Lilja's heavier Mk13 Mod7 contour, which belongs to the Mod 7. The material is disputed: a 1999 Navy spec, as quoted, says chrome moly, while the Crane builder described stainless. We don't list Lilja, so our cards are Shilen .30 caliber 1:10 barrels for your gunsmith to chamber and fit.

Neither is the Tactical taper. The second card is Shilen's #4 contour in chrome moly.

Muzzle: a plain crown or a blended thread cap

Collectors say most Mod 0s had a plain crown and no brake, and threaded ones wore a smooth blended cap. Nobody has confirmed a Mod 0 thread pitch. The 5/8-24 you'll see comes from a CMP test rifle and from clones.

Chamber and Mk 248 Mod 0 ammunition

Crane built the rifle around its load, so match your chamber first.

Chamber: an A191 reamer for the original throat

Mod 0s were chambered for the A191 load, and collectors say PTG sells a Navy Mk13 reamer. We don't list reamers.

Skip the 220 grain Mk 248 Mod 1 in this chamber. Crane said in 2009 it could be fired in existing weapons, but its spec, as American Rifleman quotes it, allows a loaded length and chamber pressure beyond SAAMI. One clone owner reports every case flowing into the ejector hole, though he suspects any chamber would. Collectors advise a chamber cut for it.

Ammunition: 190 grain match loads you can buy

Mk 248 Mod 0 isn't sold to civilians, and Crane's spec called for a nominal 3,000 fps. Commercial 190 grain Sierra MatchKing loads are your stand in.

The Federal card is the GM300WM load, and the Fiocchi is a cheaper box with the same 190 grain bullet. Our .300 Win Mag ammo page tracks the price per round.

Scope, McCann MIRS rail and rings

Your year decides this whole group.

Scope base: the McCann MIRS long action rail

The Mk13 Mod 0 wears McCann Industries' Integrated Rail System, the MIRS, a 0 MOA long action rail. The 1990s rifles used M24 type or two piece Leupold bases. A collector says McCann rails entered the supply system in 2004, and later Mod 0s got the 20 MOA MIRS Rev B.

The MIRS is out of production, and a collector priced a used one at about $600 in 2023. BG Defense's clone rail fits short actions only. We don't stock one.

Scope: Leupold Mark 4 10x or Nightforce NXS, by year

The Crane builder said the 1990s rifles left with fixed 10x Leupold Mark 4 M1s, some with 16x. By 2005, collectors report, the Mk13 Mod 0 repair standard listed the Nightforce NXS 5.5-22x56. A forum poster who says he carried a Mk13 in Iraq in 2005 shared his rifle with a Leupold on a McCann rail, so both likely served at once.

No feed we checked sells the fixed Mark 4 M1 new. For a 2005 rifle you can buy the same NXS model.

Issued scopes were Nav-Spec versions with Navy reticles such as mil dots, while these carry MOAR reticles. The 3.5-15x50 is the smaller NXS some rifles wore.

Scope rings: 30 mm, 1.125 inch for a 2005 rifle

One collector says the 2005 repair standard lists rings 1.125 inches tall, a second says the issued rings were 1.125, and surplus sets include Nightforce logo rings. The issued model isn't documented, so ours are stand ins, and the Leupold Mark 4 suits a 1990s rifle.

Some builders run 1.265 inch rings, as the American Sniper film rifles did, one collector says. That height isn't the issued one.

Bipod, sling and suppressor

You can buy two of these new. The third is an NFA item.

Bipod: a Harris on the fore end stud

Mod 0s wore a Harris on the fore end stud. The Scout list names the HBLM, which we read as the 9 to 13 inch notched leg 1A2-LM. Our card is that 1A2-LM.

Sling: M1907 leather or Turner

The Scout list gives an M1907 leather sling, NSN 1005-00-714-1245, or a Turner NMSRS-54, on Uncle Mike's QD swivels. Our sling card is U.S. Spec's Model 1907 pattern leather sling. It's sold as a parade sling, not a contract one, so treat it as a stand in. The issued swivel model isn't documented, so the swivel card is a 1 1/4 inch Uncle Mike's QD model.

Suppressor: none on most, a KAC Mk11 on the Mod 3

A plain Mod 0 carries no can. The suppressed Mod 3 used Knight's Armament's Mk11, the SR-25 suppressor, on a Crane barrel collar. Read more about the Mk11 Mod 0, source of the Mk11 suppressor.

Call your suppressed build Mod 3 style. We don't stock a Mk11, and AAC's MK13-SD shares only the name.

Mk13 Mod 0 variants: Mod 1, Mod 3 and the Mod 5 after it

The Mod 0 had a left handed twin, a suppressed branch and an AICS stocked successor.

Mod 1: the left hand Mod 0, by collector consensus

Collectors now agree the Mod 1 is the left handed Mod 0, with a left hand long action in a left hand A2 cut for the L lug. One such stock surfaced in 2023, and a manual image a collector posted in 2019 shows the Mod 1 as left handed.

A 2014 forum thread called it a McMillan stocked Mod 5 instead, and no official source settles it. For your build, the only factory left hand long magnum action in our feeds was out of stock.

Mod 3 and Mod 4: the suppressed branch

Collectors describe the Mod 3 as a Mod 0 barrel with a pinned journal for the Mk11, under a 20 MOA MIRS Rev B. One calls the left handed version the Mod 4.

CMP's April 2025 Mod 3 had a Remington long action, a bolt marked "MK 13 MOD 3," a McCann rail and, per TFB, a painted McMillan. Collectors say CMP's lots were assembled from parts, so treat none as an issued reference.

Mod 5: the AICS chassis that replaced the McMillan

From the mid 2000s the Mod 5 moved the Remington long action into an Accuracy International AICS 2.0 chassis with a Remington MARS rail. See the AICS stocked Mk13 Mod 5 that replaced it and the Marine Corps Mk13 Mod 7, announced in 2018.

The Mk 13 Mod 5 as pictured in NSWC Crane's 2009 briefing: a Remington 700 long action in an AICS 2.0 chassis with a three sided MARS rail. It replaced the McMillan stocked Mod 0 and Mod 1 from the mid 2000s, so it isn't a Mod 0. U.S. Navy, Naval Surface Warfare Center Crane, public domain, via Wikimedia Commons.

What the internet gets wrong about the Mk13 Mod 0

Encyclopedias, clone sellers and auction write ups repeat the same errors.

A grenade launcher shares the Mk 13 Mod 0 name

FN's 40 mm grenade launcher for the SCAR, the FN40GL, is also designated Mk 13 Mod 0, and Wikipedia cites a 2011 Crane notice using that name. Search GunPartPicker for "mk13" and you'll get AAC suppressors and an upper with a Geissele MK13 rail.

Wikipedia's Mk13 specs are mostly Mod 5 specs

Wikipedia's Mk 13 article leads with an AICS 2.0 chassis, and its infobox lists a 5 round magazine, a Nightforce ATACR and 11.4 lb. All four belong to the Mod 5 and Mod 7. Its 26.5 inch barrel and 47.5 inch length do match the 1999 spec quote for the McMillan rifle.

Grokipedia adds a 1988 fielding, iron sights and 12.5 lb. No builder, collector or maker source backs any of it, and the load wasn't cleared until November 1993.

Wasdin and O'Neill as users: no citation

Wikipedia lists Chris Kyle, Robert O'Neill and Howard Wasdin as Mod 0 users without a citation. Wasdin's SEAL service ran from 1987 to 1995, before the Mk13 name, and we couldn't confirm what O'Neill used.

The 2023 CMP Mod 3 was a test rifle

CMP's 2023 Mod 3 had a 26.5 inch 416R barrel threaded 5/8-24 with a four prong brake, per TFB. Chris Higgins, in an account a collector relayed, said it was a silencer test rifle for the Mod 7 contract, built on a Mod 5 chassis.

A 2025 blog post called the next CMP rifle an AICS platform. TFB describes its painted McMillan and standard floorplate.

What you can buy today and what is unobtainable

We list six of the 13 slots that need a part. Five are sold new elsewhere, and two turn up only used.

Mk13 Mod 0 parts in stock on GPP today

Here's what we list for a 2005 era Mod 0, at the lowest in stock prices on 27 September 2026.

Our builder handles AR and Glock builds only, so you can't open a Mk13 build.

Sold elsewhere: the action and extractor

These were in stock in our merchant feeds on 27 September, but we don't list them yet.

McMillan sells its reproduction A2s direct, and Lilja lists the Tactical taper on its own chart.

Gone: the MIRS rail, Crane lug and Leupold 10x

No feed we checked sold these new: the MIRS, the Crane L lug, the fixed Leupold Mark 4 M1, the Leupold Ultra, Mk 248 Mod 0 and the Kalispel case. Honest stand ins, marked not issued, are a standard lug with a dummy screw, an A3 and a plain 0 MOA long action base.

Turnkey look alikes, and why most are not a Mod 0

No merchant we carry sells a finished Mod 0 clone. BG Defense's trainer looks close but runs a short action in .308 Win or .300 WSM, in an A3. Private sellers list "Mk13 Mod 0 spec" rifles in classifieds, so check any listing for the four tells: long action, A2, L lug and MIRS.

What a Mk13 Mod 0 clone costs today

On 27 September 2026 the six parts we list came to $2,553.64, and the action sold elsewhere added $599.99. We don't estimate what we can't price: the A2, the MIRS, the L lug, BDL bottom metal and your gunsmith's time.

The civilian legal path to a Mk13 Mod 0 clone

A plain Mod 0 involves no NFA item. Only a Mod 3 style suppressor does.

A plain Mod 0 or Mod 1 needs no NFA paperwork

The Mod 0 is a bolt action, so there's no select fire part to swap for a semi auto one. Its 26.5 inch barrel is far past 16, so you don't need a pinned and welded muzzle device or SBR paperwork. The action ships to your FFL like any receiver.

A Mod 3 style suppressor is the only NFA item

A Mk11, like any suppressor, is an NFA item. ATF announced on October 9, 2026 that it would stop enforcing Form 4 and Form 1 approval for suppressors, though it still accepts both at $0, so check your state's suppressor law before you buy. See our guides to the ATF paperwork rule and suppressor paperwork in 2026. Before that change, builders bought the can first and built the rifle during the wait.

Mark reproduction parts so it cannot pass as issued

Clone builders mark reproduction bolts, barrels and lugs so nobody can sell the rifle as issued later. Sellers of surplus Mk13 stock kits also say ITAR rules bar shipping them abroad.

Sources and photo credits

Where each fact in this guide comes from

Where to see photos of original rifles and clones

No public domain photo of a Mod 0 or Mod 1 turned up on Wikimedia Commons or DVIDS, and the photos collectors cite have unknown licenses. So we link you to rifles instead. The Sniper's Hide stock thread shows surplus stocks, lugs and rails, and the build thread shows clones on original stocks.