Does the Stern Defense SD 4in MOD4 M-LOK 4in work with the Stern Defense Nickel Boron 9mm?

Stern Defense SD 4in Mod4 M-Lok 4in Barrel 9mm Black Complete Upper Receiver Black SDINBRLKK

Upper Receiver

Stern Defense SD 4in MOD4 M-LOK 4in Barrel 9mm SDINBRLKK

from $419.27

Stern Defense Nickel Boron 9mm Complete Bolt Carrier Group - SD BU9 NiB ECHO

Bolt Carrier Group

Stern Defense Nickel Boron 9mm

from $169.99

Stern Defense upper and Stern Defense bolt carrier group compatibility

Yes, they fit

The Stern Defense SD 4in MOD4 M-LOK 4in Barrel 9mm works with the Stern Defense Nickel Boron 9mm. Our compatibility rules found no conflict between them.

This exact setup has been built more than once on GunPartPicker.

Counted from real GunPartPicker builds: parts lists people put together while planning to buy.

Checked by the same rules the AR builder runs on every part you add: caliber, frame size, receiver pattern, thread pitch and gas length.

Fit is judged from the specs retailers list, which can be missing or wrong. Confirm with the manufacturer before you buy, and have a qualified gunsmith check any build before you fire it.

How often builders pair the Stern Defense upper and Stern Defense bolt carrier group

Backed by thousands of qualified builds that have both an upper and a bolt carrier group.

Bolt Carrier Groups builders put on the Stern Defense SD 4in MOD4 M-LOK 4in

Share of builds with the Stern Defense SD 4in MOD4 M-LOK 4in and any bolt carrier group

Upper Receivers builders put under the Stern Defense Nickel Boron 9mm

Share of builds with the Stern Defense Nickel Boron 9mm and any upper

  • Stern Defense SD 4in MOD4 M-LOK 4in

    Of upper picks
    0%
    Median paid
    $419

  • Stern Defense Nickel Boron 9mm

    Of bolt carrier group picks
    0.2%
    Median paid
    $170
How we count ⌄

These shares come from GunPartPicker's build data: real parts lists people put together while planning a purchase, not sales or surveys. A build counts a part only when it is the final pick for its slot, so parts that were swapped out never count. Fit never comes from these numbers; it comes from our compatibility rules alone.

Frequently built with the Stern Defense upper and Stern Defense bolt carrier group

The part builders pick most often in each slot alongside these two, checked against both. Parts that conflict are left out.

Charging Handle

Lower Receiver

Trigger

Light

Stock & Brace

Pistol Grip

Optic

Handguard

Stern Defense SD 4in MOD4 vs Stern Defense Nickel Boron 9mm: specs and prices

Stern Defense SD 4in MOD4Stern Defense Nickel Boron
Best price$419.27 at Optics Planet$169.99 at Optics Planet
Stores1 of 1 in stock3 of 4 in stock
AssemblyCompleten/a
PlatformAR-9n/a
Caliber9mmn/a
Length4n/a
Cartridgen/a9mm
Finishn/aNickel Boron

Both for $589.26 at today's best prices.

Today's best prices and 90 day price history

Every store we track for each part, cheapest in stock first. Prices are checked through the day.

Stern Defense SD 4in MOD4 M-LOK 4in Barrel 9mm

Stern Defense Nickel Boron 9mm

Price history, last 90 days

  • Stern Defense SD 4in MOD4 M-LOK 4in: lowest $376.96 on Jul 5, highest $419.27 on Jul 12 over the last 90 days.
  • Stern Defense Nickel Boron 9mm: lowest $144.49 on Jul 5, highest $170.99 on Jul 24 over the last 90 days.

Bolt Carrier Groups most paired with Stern Defense uppers

The Stern Defense SD 4in MOD4 M-LOK 4in is not in enough builds yet, so these are the most picked next to any Stern Defense upper. Only parts our rules say fit the Stern Defense SD 4in MOD4 M-LOK 4in are listed.

Upper Receivers frequently paired with the Stern Defense Nickel Boron 9mm

Most picked next to it in real builds. Only parts our rules say fit the Stern Defense Nickel Boron 9mm are listed.