Radical Firearms 5.56 Pistol RPR M-LOK SBA3 - 7.5"

Manufactured by Radical Firearms
SKU: FP7.5-5.56M4-7RPR-SBA3
MPN: FP7.5-5.56M4-7RPR-SBA3
Manufactured by Radical Firearms
2 Reviews

Out of Stock

NOTE: Limit 20 per household. Quantities exceeding 20 will not allow checkout.

Items that are regulated by the ATF have restrictions and requirements: 
•Your entire order will ship only to a Federal-Firearm License holder.
•Please contact your local FFL prior to placing your order to ensure they are still accepting transfers.
•A copy of your order/invoice as well as the current FFL license for your local dealer must be emailed to ffl@primaryarms.com.



The Radical Firearms 5.56 AR Pistol has been upgraded for 2019 with the popular SB-Tactical SBA3 5 position adjustable arm brace. This stabilizing brace is extremely durable and rigid with plenty of adjustment for different arm lengths and features a QD sling swivel slot for carrying or added stability when shooting off hand. It also allows for a proper cheek weld giving you a variety of ways to shoot your AR pistol. This model comes with a 7.5” barrel machined from 4140 Chrome Moly steel with a Melonite finish and a 1:7 twist rate. A popular twist rate for heavier 62 grain projectiles combined with a pistol length gas system make for an accurate and reliable system. M4 feed ramps help to angle the cartridges into the chamber and help to prevent FTF malfunctions. The Radical Firearms 5.56 pistol paired with the SBA3 stabilizing brace make this gun extremely fun at the range.

  • 7.5” barrel chambered in 5.56 NATO
  • Machined from 4140 steel with Melonite finish
  • M4 barrel profile
  • 1:7 twist rate
  • Pistol length gas system
  • .750” low profile gas block
  • A2 style flash hider
  • Forged 7075-T6 aluminum receivers
  • Type III anodized
  • 7” RPR free float handguard
  • M-LOK compatible
  • Mil-Spec parts kit
  • Ambidextrous safety and billet magazine button
  • Billet extended bolt catch
  • Mission First Tactical Ergo pistol grip
  • SBA3 pistol arm brace

This 5.56 NATO pistol features an upper and lower receiver forged out of 7075-T6 aluminum and a type III anodized finish for added durability and corrosion resistance. It is assembled with mostly Mil-Spec parts; however, it features an ambidextrous safety selector, Mission First Tactical Ergonomic pistol grip, and a billet machined magazine button. Also included is the Radical Firearms 7” RPR M-LOK handguard. This handguard comes with a few features of its own like an extremely durable barrel nut that free floats the barrel for better accuracy and indexes with the upper receiver to prevent it from rotating loose. It features lightening cuts to reduce weight and a continuous picatinny top rail for iron sights and other accessories. The slim and minimal design is extremely comfortable and lightweight to use without sacrificing the ability to set your gun up exactly the way that you want.

Radical Firearms offers law enforcement grade hardware. Crafted with quality materials and covered by their lifetime warranty, Radical Firearms is an outstanding choice for any budget.
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Barrel CoatingMelonite
Barrel ContourM4
Barrel Length7.5
Barrel LiningMelonite
Barrel Material4140 Chrome Moly Steel
BrandRadical Firearms
Caliber Gauge5.56 NATO
Frame SizeAR Pistol
Gas System LengthPistol
Gas System TypeDirect Impingement
Handguard7 in M-LOK Rail
Thread Pattern1/2 X 28
Twist Rate1:7

WARNING: This Product can expose you to chemicals which is known to state of California to cause Cancer and Reproductive Harm. For more information, see www.p65warnings.ca.gov

Ratings & Reviews

2 reviews

  • 3 stars
  • 0 reviews
  • 2 stars
  • 0 reviews
  • 1 star
  • 0 reviews

The Perfect Size for my Needs/Want or Both


I had been told from some buddies that if I went shorter than a 10" barrel I would pay for it with some loss of accuracy. While that is true, for my needs, it wasn't like I was going to be attempting any 700 yard shots at any point. This weapon feels balanced when holding it at the ready position. This sale went as they said it would. It arrived at my FFL on the exact date that had been previously established. That is amazing when still in the middle of a pandemic. I have ran 150 rounds with zero problems, alternating from 25-50-100 yards. I will say that after 60 rounds I upgraded my hearing protection. There is so much rail space I had to put it to good use, first with Magpul Pro iron sights, then a Vortex Red Dot, and last a Vortex Magnifier (which I probably didn't need). I know this is on the economy end of the AR Pistol spectrum, but it is exactly what I was looking for, and it is gold to me. And pricewise, this was and is a good deal.

Nice gun, fun to shoot, get them before they go up in price again.


I picked one of these up in December. Only $648.00 then. Put some flip down sights and a red dot scope on it. Finally found enough ammo to sight both sights and scope in last week. It shot very well. The only complaint I have is the bolt release button. You really have to push on it hard to release the bolt when loading. Accurate and no malfunctions. I was shooting 62 grain, green tip ammo. I would give it a 5 if not for the bolt release issue.