Radian Ramjet Review: 300 Rounds Through the Glock 43X MOS Barrel + Comp System

The Glock 43X MOS is an excellent concealed carry platform on paper: slim, optics-ready, 10+1 capacity with Shield Arms magazines pushing that to 15+1. In practice, it recoils harder than you would expect from a 9mm. The slim frame, light weight, and high bore axis combine to produce a snappy, uncomfortable shooting experience that erodes confidence over extended range sessions.

My 43X MOS had an additional problem: a defective RSA (recoil spring assembly) from the factory, labeled "101." If yours has the same marking, contact Glock warranty for a replacement. So much for Glock Perfection. Between the factory spring issue and the baseline recoil characteristics, the gun was genuinely unpleasant to shoot.

The fix involved two changes: a new recoil spring from Glock warranty and the Radian Ramjet + Afterburner compensated barrel system. The combination transformed the gun.

The Radian Ramjet is a match-grade barrel, and the Afterburner is the compensator that attaches to it. They are sold as a matched package for $389. The system is designed specifically for the Glock 43X/48 slimline frame, maintaining the slim profile that makes the platform attractive for carry in the first place.

What separates this from most compensator setups is the attachment method. The Afterburner uses a tapered interface rather than standard barrel threading. It locks onto the Ramjet barrel mechanically, with no thread locker required. This eliminates the two biggest reliability concerns with pistol compensators: the comp loosening and walking off the barrel during firing, and the need to retune the recoil spring to compensate for gas bleed. There is also a legal advantage: because the Ramjet barrel has no threads, the entire system is 50-state legal. States like California that restrict threaded barrels on pistols are not an issue here.

The Ramjet works with the stock Glock recoil spring. That is a significant advantage. Most standalone compensators bleed enough gas to short-stroke the slide unless you swap to a lighter spring, which introduces its own reliability questions. The Ramjet skips that entire headache. For a deeper comparison of compensator types and attachment systems, see our Glock compensator guide.

After installing the Ramjet and the replacement recoil spring, the Glock 43X genuinely feels like a new gun. The muzzle rise is visibly reduced, the recoil impulse is softer, and follow-up shots come faster with less effort. The difference is not subtle.

Across 300 rounds of mixed 115gr and 124gr FMJ, the system produced zero malfunctions. No failures to feed, no failures to eject, no short-stroking. The stock Glock spring handled both loads without issue, confirming Radian's claim that no spring swap is needed.

Practical accuracy improved noticeably, though I would attribute this to shootability rather than inherent barrel accuracy. The stock Glock barrel is accurate enough for defensive distances. What changed is how easy it is to keep the sights on target through a string of fire. The reduced muzzle flip translates directly to tighter groups at speed, which is what actually matters in a concealed carry pistol.

Here is where the trade-offs get real. Every compensator redirects gas upward to push the muzzle down, and that gas has to go somewhere. With 115 grain ammunition, the Ramjet produces a massive flash signature. It is genuinely startling, even outdoors in daylight. At an indoor range or in a defensive scenario, that flash would be blinding.

The 124 grain loads are better but still produce more flash than a standard barrel. The noise and concussion are also increased across both loads. If you have ever stood next to someone shooting a compensated pistol at an indoor range, you know the pressure wave is unpleasant for everyone in the bay. Now imagine that in a hallway in your house at 2 AM.

This is the honest trade-off of running a comp on a carry gun: you get better shootability at the range, but the blast characteristics in a confined defensive scenario would be disorienting. If you carry quality defensive ammunition (124gr or 147gr hollow points), the flash issue is reduced but not eliminated. It is a calculation each carrier has to make for themselves.

The bronze Ramjet barrel paired with the black Afterburner compensator looks exceptional. This is a subjective point, but the two-tone finish gives the 43X a distinctive, premium appearance that the stock barrel does not.

More practically, the Ramjet + Afterburner adds roughly half an inch of overall barrel length. This was a concern for holster fit, but the T.REX Arms Raptor for the standard Glock 43X accommodates the compensated barrel without any issues. The fit is clean enough that it looks purpose-built, even though the holster was not ordered with the Glock 48 or threaded barrel option. Most quality Kydex holsters with an open bottom will handle the extra length, but verify with your specific holster before committing.

The Radian Ramjet + Afterburner made me love my Glock 43X. That is not hyperbole. A gun I found unpleasant to shoot is now one I look forward to taking to the range. The recoil reduction is substantial, the reliability has been perfect, and the tapered barrel design solves the two worst problems with pistol compensators (loosening and spring retuning) in a single package.

The only reason this is not a 5/5 is the defensive shooting question. If you carry the 43X for self-defense, you are adding a compensator to a gun you might need to fire indoors, potentially without ear protection. The increased concussion, noise, and flash are real concerns that deserve honest consideration. Running 124gr or 147gr defensive loads helps with flash, but the concussion is inherent to the design.

If you are looking for more ways to improve your 43X, check our complete Glock 43X upgrades guide for ranked optics, triggers, lights, and magazine options. G19 owners can find their equivalent in our Glock 19 upgrades guide. You can also use our pistol barrel catalog to compare the Ramjet against other compensated barrel systems.

Recommended for anyone who wants a more shootable Glock 43X and accepts the compensator trade-offs. At $389, it is not cheap, but the engineering quality and the fact that it just works with no tuning justifies the price.