Does the Fortis Billet M4 Upper Stripped work with the Spike's Tactical 5.56 NATO Cut?

Upper Receiver
Fortis Billet M4 Upper Stripped
from $189.95

Bolt Carrier Group
Spike's Tactical 5.56 NATO Cut Lightweight
from $201.75
Fortis Manufacturing upper and Spike's Tactical bolt carrier group compatibility
Yes, they fit
The Fortis Billet M4 Upper Stripped works with the Spike's Tactical 5.56 NATO Cut Lightweight. 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 Fortis Manufacturing upper and Spike's Tactical bolt carrier group
Backed by thousands of qualified builds that have both an upper and a bolt carrier group.
Share of builds with the Fortis Billet M4 Upper Stripped and any bolt carrier group
- This pairSpike's Tactical 5.56 NATO Cut Lightweight14%
Share of builds with the Spike's Tactical 5.56 NATO Cut and any upper
- This pairFortis Billet M4 Upper Stripped0.9%
Fortis Billet M4 Upper Stripped
- Of upper picks
- 0.1%
- Median paid
- $167
Spike's Tactical 5.56 NATO Cut
- Of bolt carrier group picks
- 2.2%
- Median paid
- $202
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 Fortis Manufacturing upper and Spike's Tactical 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

Radian Raptor & Talon Safety Selector Combo
Unconfirmed
Stock & Brace
Pistol Grip
Gas Block
Suppressor
Barrel
Fortis Billet M4 Upper vs Spike's Tactical 5.56 NATO Cut: specs and prices
| Fortis Billet M4 Upper | Spike's Tactical 5.56 NATO | |
|---|---|---|
| Best price | $189.95 at Optics Planet | $225.00 at Primary Arms |
| Stores | 4 of 5 in stock | 4 of 5 in stock |
| Assembly | Stripped | n/a |
| Platform | AR-15 | n/a |
| Caliber | .223 Wylde | n/a |
| Receiver Type | Billet | n/a |
| Cartridge | n/a | 5.56 NATO |
| Style | n/a | Low Mass Bolt Carrier |
| Finish | n/a | Nickel Boron |
| Weight | n/a | 10.5 |
Both for $414.95 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.
Fortis Billet M4 Upper Stripped
Price history, last 90 days
- Fortis Billet M4 Upper Stripped: lowest $167.16 on Jul 5, highest $210.99 on Sep 27 over the last 90 days.
- Spike's Tactical 5.56 NATO Cut: lowest $201.75 on Sep 4, highest $225.00 on Jul 5 over the last 90 days.
Bolt Carrier Groups frequently paired with the Fortis Billet M4 Upper Stripped
Most picked next to it in real builds. Only parts our rules say fit the Fortis Billet M4 Upper Stripped are listed.
Upper Receivers frequently paired with the Spike's Tactical 5.56 NATO Cut
Most picked next to it in real builds. Only parts our rules say fit the Spike's Tactical 5.56 NATO Cut are listed.




















