Lightweight precision rifle suppressor
.338 Lapua Magnum caliber
Brake Attach (BA) and Secondary Retention (SR) versions

UPDATED/EXPANDED FOR 2024 - Added Reduced Recoil / Race Ready "RR" variants available!

L to R: 338 Ultra-BA, 338 Ultra-RR-BA, 338 Ultra-SR, 338 Ultra-RR-SR

The RR variants of the 338 ULTRA almost double the recoil reduction (compared to a bare muzzle) of the normal flat-cap version of the suppresor. On 338LM, the 338 ULTRA-RR has a recoil reduction of 54% --- vs normal version 32%. For more details on the 338 ULTRA RR sound reduction and recoil reduction, please consult the PDF with all the Magnus RR and 338 Ultra RR data.

The second-generation 338 ULTRA ("Gen2") superseded the original model January 2022. The Gen2 is quieter than the original version by about 3 dB. Gen2 338 Ultras can be identified by serial numbers that are higher than E10000.

The new 338 ULTRA is the quietest .338 caliber suppressor on the market today for everything up to .338 Lapua Magnum, including your 6's, 6.5's, 7's, and .30's. It offers class leading suppression levels with extreme light weight.

The 338 ULTRA is available in two versions:

(1) The 338 ULTRA has the original TBAC large Brake Attach (BA) brake attachment, the same mount as the original 338 ULTRA, and older 30BA series. This design is backwards compatible with all 338BA and 30BA brakes. It can be used on our smaller CB brake mounts with the addition of a CB2BA adapter.

(2) The 338 ULTRA SR has the same SR (Secondary Retention) mount as our Dominus-SR, Dominus-K-SR, and Magnus-SR. This model is 0.60-inch longer and 2.8 ounces heavier than the BA version. This version has the same Hard-Use/Full-Auto as the DOMINUS-SR, ie, Lifetime to exceed at least 10 SURGE cycles on a 10.5" M4 / MK18. The BA version of the 338 ULTRA is NOT full-auto rated due to the mount being insufficient. The GEN2 SR weight is 0.2 ounces lighter than the GEN1 version.


We've also fully characterized the sound performance using the same methodology we as the 2023 SILENCER SUMMIT. The data for "most" of our current suppressors is here, with experimental and analysis documentation: Full Sound Test Results of most current TBAC suppressors (with waveforms).

The SR Mount System

This video explains the SR mount system and its applications on a precision rifle suppressor

This mount meets the mil spec represented in the 2017 Advanced Sniper Rifle (ASR) solicitication, and the 338 ULTRA SR is the suppressor that Accuracy International North America chose for their ASR rifle system submission.

The main feature of the SR mount is that it acts as a secondary, fail-safe, locking mechanism to retain the suppressor on the muzzle brake in all circumstances, unless explicitly removed on purpose, by hand. It also reduces the number of turns required to mount the suppressor due to a coarser thread and enables "Quick Mount" and "Quick Detach" functionality of the mount. The mount is mechanically very simple and user-level maintenance is possible.


The SR mount uses a novel paw and cam-path system to ensure that "full lock up" can happen in either of the two adjacent detent slots for any given final shouldering position of the suppressor on the conical brake shoulder. This categorically avoids the "off-by-one" problem that many "clicky" mounts have. The SR mount has the exact same accuracy, repeatability, and return-to-zero characteristics that all our precision suppressors are known for.

This mounting system is covered by US Patent 9,791,234.

Link to the SR mount Operator and Armorer-level instruction manual.


The ULTRA Gen2 series represents a revolutionary improvement in titanium precision rifle suppressors. We took everything we've learned over the last decade building the best precision rifle suppressors in the world and put it into the ULTRA design. The ULTRA series offers unprecedented light weight and class-leading suppression levels.

Like the original, the Gen2 ULTRA is all-titanium and is fully welded. The Gen2 is now a "tubeless" design, with the baffles joined directly with no separate tube. This material and construction provide a great strength to weight ratio. It can take whatever your precision rifle can dish out.

The ULTRA Gen2 baffle stack was completely redesigned, but retains the principles that made the original ULTRA (and 30P-1 stack before that) such a great precision and long-range suppressor. Thunder Beast Arms Corp suppressors have racked up impressive results at long-range field shooting events nationwide, and have been the most popular suppressor used in the Precision Rifle Series (top 50 competitors) for many years running.

The 338 ULTRA was designed around .338 Lapua Magnum for maximum flexibility and is rated with that cartridge down to 16" barrels. The 338 ULTRA can easily do multiple-rifle duty on 6mm's, 6.5's, .260's, .308, and most .30 caliber magnums.

Special Features

Ionbond DLC coating on 338BA brakes
Conical shoulder surface on mount
100% titanium construction
"Tubeless" construction
360-degree fully-welded baffle stack
Helical Baffle Technology
Magnum rated
Rock-Solid POI Repeatability


"At the muzzle" (M) sound measurements are measured in accordance with MIL-STD-1474D using a B&K PULSE SLM one meter offset from muzzle of the suppressor. These are also referred to a "milspec-left" (ML) and "milspec-right" (MR)

"At Shooter's Ear" (SE) measurements are measured in accordance with MIL-STD-1474D using a B&K PULSE SLM at the position of the shooter's right ear in a normal shooting position. SE measurements are affected by overall rifle length.

To isolate the muzzle suppression from the supersonic crack (the "shockwave"), the shockwave pulse is omitted from peak measurements. Please refer to this video for more information: Thunder Beast education video #1. Sonic Crack. Per the video the supersonic crack presents an extremely short impulse in centerfire rifles that is 130-134 dB measured at the ML/MR and presents approximately 120-124 dB at SE (exact number varies based on caliber). For additional information on shockwave, please excerpts from the NATO document here.

Bolt action rifles will always be quieter than semi-autos due to the "port pop", IE, gas pressure escaping through the action. On AR-10/AR-15 "gas gun" platforms, this port pop will almost always dominate the Shooter's Ear (Se) dB number. The port pop of a gas gun can often be reduced substantially by tuning the gas system.

For centerfire semi-auto pistols, the sound pressure that escapes the breech is considerable and, due to shorter barrel lengths, influences both muzzle dB and shooter's ear dB numbers.


Caliber .338 caliber, up to .338 Lapua Magnum or .338 RUM
Material Titanium
Diameter body 1.8 inches; collar 1.85 inches
Mount 338BA Brake (v1 or v2) (BA version)
SR brake (SR version)
Brake Threads 9/16-24, 9/16-28, 5/8-24, 3/4-20, 3/4-24, 3/4-28, M18x1.0, M18x1.5
Brake Material Heat-treated 17-4 stainless
Brake Finish Ionbond DLC
Finish Black CeraKote; OD Green and FDE available
Use Precision/Long-range on big-bore magnums
Hard-Use/Full-Auto (SR variant)
Suppression PerformanceLink to comprehensive metering results
Warranty TBAC Limited Lifetime Warranty
How to order a suppressor


338BA Brake
Each brake includes one peel washer
* Barrett .338 rifles manufactured prior to 1/2013 use MRAD brake; manufactured after 1/2013 use 3/4-24 brake.
SR Brake

338BA External Thread Protector

Extra Peel Washers
Peel washers have an O.D. of 0.840-0.845"
and an initial thickness of approx 0.048-0.055".
Shipping for web orders is $8.65 for the first item and $4.33 for each subsequent item, for most products. Shipping cost on external thread protectors and extra peel washers is less. Bipods are more.


NOTE: The collar is not intended to stay perfectly parallel/square to the body when locked. The play is there on purpose for clearance so foreign material does not compromise functionality of the locking mechanism.


5.5" .300 Blackout (Full power and Subs), 6.8 SPC, 7.62x39,
8" .308, 6.5 Creedmoor, .260 Rem, 6 Creedmoor, .243 Win, .22 Creedmoor, .223/556 (SEMI AUTO)
10.3" .223/556 (FULL AUTO per Dominus-SR schedule)
12" 26 Nosler, 6.5 SAUM, 6.5 PRC, 7 WSM, 7 SAUM, 7 STW, 7 RM, 300 WSM
14.5" 300 PRC, 300 RUM, 7 RUM, 300 WM, 300 WBY, 6.5-300 WBY
16" 300 NORMA, 28 Nosler, 338 LAPUA, 338 NORMA
For questions about a particular rifle/load combination please contact us.


On the MAGNUS and 338 ULTRA, we recommend weighing them every 500 rounds. At this point, if the weight added due to deposited carbon exceeds 1 ounce, we recommend using our cleaning procedure until the suppressor is back to its orginal weight. Link to TBAC recommended cleaning procedures.

The GEN2 338 ULTRA and MAGNUS suppressors work by trapping and holding gas which means they gain carbon faster than the GEN1.


Follow the Youtube links for the dB data breakout on any of these.