Spike's Tactical 16" 5.56 M4 LE Complete AR-15 Upper - with Front Sight Base

Manufactured by Spike's Tactical
SKU: STU5025-M4S
MPN: STU5025-M4S
Manufactured by Spike's Tactical
24 Reviews

In Stock

Standard orders will ship out in 1 business days or less if ordered by 3:30 pm CST, Monday-Friday. FFL orders will ship within 5 business days or less as long as we have the information for the transfer destination. NFA items will take longer to ship and are dependent upon ATF processing times.

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The Spike's Tactical 16" 5.56 M4 Carbine Complete Upper offers the same level of quality and performance available in all their rifles. Spike’s Tactical maintains a high standard of tolerances and attention to detail in the uppers they use for complete rifle builds. Every complete upper is test fired before leaving their facility and is backed by the Spike's Tactical lifetime warranty.

  • 7075-T6 forged aluminum upper receiver. 
  • Forward assist and ejection port door.
  • 16" 5.56 NATO, chrome lined, M4 profile barrel with carbine length gas system.
  • 41V50 chrome moly vanadium steel with phosphate coating.
  • 1/2x28 thread pitch with a 1:7 twist rate.
  • M4 feed ramps.
  • Pinned A2 front sight base.
  • Double heat shielded M4 handguard.
  • Standard charging handle.
  • Phosphate coated, M16 cut, complete bolt carrier group.
  • BCG high pressure tested and magnetic particle inspected.
  • A2 flash hider.
  • Weight: 4 lbs 2 oz.
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Barrel ContourM4
Barrel Length16
Barrel Material41V50 Chrome Moly Vanadium Steel
BrandSpike's Tactical
Caliber Gauge5.56 NATO
Gas System LengthCarbine
Gas System TypeDirect Impingement
HandguardCarbine Length Drop-In Handguard
Muzzle DeviceA2 Flash Hider
Twist Rate1:7
California Prop 65 warning

 WARNING: This product can expose you to chemicals, which are known to the State of California to cause Cancer and Reproductive Harm. For more information go to www.P65Warnings.ca.gov.

Ratings & Reviews

24 reviews

  • 4 stars
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Great Products - Great Prices - Fast Shipping -


2 orders in a row, 1st order was a spikes upper, in my hands 2 days later, 2nd order was a Primary Arms 4-16x44 scope, in my hands 2 days later, mounted it and zeroed yesterday, good glass, holds zero after 200 rounds of 308 handloads. Very happy with products, prices, and shipping. My order from another vendor is still pending shipping after 2 weeks.

Love it.


First AR I've built and Spikes hasn't let me down. Would look nicer if it had a smaller hand guard on it, but, that was easily remedied.

Very pleased with purchase


I added this complete upper to lower build using a Spikes forged lower. This upper mated perfectly to my lower build - tight with only the smallest hint of wiggle. Fit and finish are superb... Barrel made by FN... Premium Spikes BCG and bolt... What's not to like?Highly recommended if you're looking for a quality M4-style upper at an attractive price.

Great deal,Nice upper !!!


I decided I needed a couple of uppers for my builds.I saw slickguns had a coupon for 15% off spike's.I knew and have ordered from Primary before,good deal then as well.I ordered it on Friday.I received it on Saturday.Came by rocket ship apparently!!!Very nice upper,all spike's and no blemishes that I could find.So guess what ,I just ordered another one before sale ends.I really don't need it,but I feel I cant afford not to order 1 more lol.Thanks Primary and happy MO day everyone !!!!

Spikes upper


I have made smaller purchases with Primary Arms before so my expectations were naturally high. Those expectations were exceeded by the upper receiver arriving ahead of schedule. Better than expected is becoming increasingly expected!

spikes tactical .556 A2 carbine complete upper


I needed this upper to complete a spikes lower receiver I had built. Primary Arms was the only place that had any Spikes uppers in stock period..... The price was great and I received it very quickly and in fine order. I will be buying from you guys in the future, definitely!! Thanks allot , you made my gun exactly what I wanted.

Super deal


I never submit reviews unless I am totally impressed by a product. Well, I am totally impressed! I put this upper on my S&W MP 15 and it fits nice and tight without any play to the lower reciever. The bolt is very rugged, and the double shield handguards are a nice bonus. The keyhole forging mark is present on the upper, and it has the proper 'F' marked mil spec sight. Its an awesome deal. Hope this helps.

A+ upper and service


I put this upper on my spikes punisher edition lower. Excellent quality and smooth operation. Have put 120 rounds through it with no FTF or FTE. Definitely exceeded my expectations. And primary arms was lightning fast on shipping, ordered on a Thursday morning and received on Saturday. Will be getting some primary arms optics soon to go on it.

Spikes complete upper


I'm very happy with this upper. It showed up three days after I placed the order. This weekend i'm going to take it out range. It fits my m&p 15 lower perfectly. Feels solid and looks nice.

Spikes M4 upper - great


Mated w/ a Spikes lower...they fit tight ...as they should...also replaced the M4 handguard w/ a quad rail and added Magpul rear sight...Very happy...Also, Primary's was tip-top!!