Does the Harrington & Richardson Retro M16A1 work with the Expo Arms 5.56 NATO Barreled Upper?

Lower Receiver
Harrington & Richardson Retro M16A1 Lowers Receiver
from $159.99

Upper Receiver
Expo Arms 5.56 NATO Barreled Upper
from $279.99
Harrington & Richardson lower and Expo Arms upper compatibility
Yes, they fit
The Harrington & Richardson Retro M16A1 Lowers works with the Expo Arms 5.56 NATO Barreled Upper. Our compatibility rules found no conflict between them.
This exact setup is in a real GunPartPicker build.
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 Harrington & Richardson lower and Expo Arms upper
Backed by tens of thousands of qualified builds that have both a lower and an upper.
Share of builds with the Harrington & Richardson Retro M16A1 and any upper
- This pairExpo Arms 5.56 NATO Barreled Upper7%
Share of builds with the Expo Arms 5.56 NATO Barreled Upper and any lower
- This pairHarrington & Richardson Retro M16A1 Lowers11%
Harrington & Richardson Retro M16A1
- Of lower picks
- 0.1%
- Median paid
- $160
Expo Arms 5.56 NATO Barreled Upper
- Of upper picks
- 0.1%
- Median paid
- $280
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 Harrington & Richardson lower and Expo Arms upper
The part builders pick most often in each slot alongside these two, checked against both. Parts that conflict are left out.
Rifle Scope
Bolt Carrier Group

PSA 5.56 Full-Auto Nitride MPI
Fits both
Pistol Grip
Stock & Brace
Barrel

FN America FN 16 Mid-Length 5.56mm
Fits both
Muzzle Device
Harrington & Richardson Retro vs Expo Arms 5.56 NATO Barreled: specs and prices
| Harrington & Richardson | Expo Arms 5.56 NATO Barreled | |
|---|---|---|
| Best price | $159.99 at Palmetto State Armory | $279.99 at Primary Arms |
| Stores | 0 of 1 in stock | 0 of 1 in stock |
| Assembly | Stripped | Complete |
| Platform | AR-15 | AR-15 |
| Caliber | 5.56 NATO | 5.56 NATO |
| Color | Gray | n/a |
| Gas System Length | n/a | Mid-Length |
| Receiver Type | n/a | A4 |
| Length | n/a | 16 |
Both for $439.98 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.
Price history, last 90 days
- Harrington & Richardson Retro M16A1: lowest $159.99 on Sep 4, highest $159.99 on Sep 4 over the last 90 days.
- Expo Arms 5.56 NATO Barreled Upper: lowest $279.99 on Jul 7, highest $279.99 on Jul 7 over the last 90 days.
Upper Receivers frequently paired with the Harrington & Richardson Retro M16A1
Most picked next to it in real builds. Only parts our rules say fit the Harrington & Richardson Retro M16A1 are listed.
Lower Receivers frequently paired with the Expo Arms 5.56 NATO Barreled Upper
Most picked next to it in real builds. Only parts our rules say fit the Expo Arms 5.56 NATO Barreled Upper are listed.


















