The Model .22 IBS (Inside Barrel Suppressor) from Suppressed Tactical Weapons, Inc. provides a visually stealthy way to silence a Ruger 10/22 by counterboring the front end of a target-weight barrel and simply screwing in a one-piece titanium suppression module. Note that the suppressed barrel is issued with a four-point rather than a two-point spanner for removing and reinstalling the suppression module. Photo by P.H. Walter
By Al Paulson
The Model .22 IBS (Inside Barrel Suppressor) from Suppressed Tactical Weapons, Inc. provides a remarkably innovative, incredibly robust, and visually stealthy way to silence a Ruger 10/22. STW begins with a standard target-weight aftermarket barrel and counterbores the front end for 8.0 inches. The one-piece titanium suppression module simply screws into the counterbored barrel. Since the barrel diameter remains unmodified, the suppressed rifle can be used in any stock designed for a target barrel without any modification whatsoever to the stock. This is a very tidy, superbly engineered, and aesthetically pleasing solution for suppressing the Ruger 10/22.
The .22 rimfire suppression module uses similar technology to the system developed by STW’s design team of Andy Andrews and Carl O’Quinn for 5.56mm and .30 caliber sniper rifles. The suppressor only has two parts: the rifle barrel and the suppression module. Furthermore, the suppression module does not use baffles and spacers in any conventional sense. Machined out of a solid block of G2 titanium, the .22 rimfire suppression module incorporates a thoroughly innovative series of asymmetric surfaces to slow and cool the hot combustion gases, robbing them of energy that would be perceived as sound. It is interesting to note, however, that the actual geometries differ considerably in basic shapes as well as dimensions for every caliber of IBS suppressor.
The patent-pending .22 rimfire suppressor module is 8.0 inches (20.3 cm) long and has a maximum diameter of 0.80 inches (20.3 mm). Suppressed Tactical Weapons installs these modules on any standard diameter, target-weight, stainless steel Ruger 10/22 barrel (with a diameter of 0.92 inch or 23 mm) in any barrel length desired by the end-user. The particular system evaluated in this study used a Butler Creek barrel with a length of 20.0 inches (50.8 cm), which was counterbored for 8 inches, leaving an effective barrel length of 12 inches but a legal barrel length of 20 inches. When combined with a Fajen laminated thumbhole stock and a Tasco World Class Plus 3×9 scope, this makes a handsome, user-friendly system.
One aspect of the system’s user-friendliness is that STW’s suppression module can be removed for cleaning and then reinstalled in the counterbored barrel without changing the zero of the firearm. Reinstalling a muzzle can, on the other hand, necessitates re-zeroing the firearm unless the suppressor is installed to precisely the same number of inch-pounds using a torque wrench. Another user-friendly aspect of STW’s system is that the suppressed barrel is issued with a four-point rather than a two-point spanner for removing and reinstalling the suppression module.
Clearly, the Model .22 IBS system is robust and innovative, but how well does it perform? To answer this question, I tested the performance of suppressed and unsuppressed Ruger 10/22 rifles using the specific equipment and testing protocol advocated at the end of Chapter 5 in the book Silencer History and Performance ($55 postpaid, check or MO, Wideworld, Dept. SAR, P.O. Box 1827, Conway, AR 72033). The microphone was placed 1.00 meter to the left of the gun or suppressor muzzle, and ammunition was kept in an insulated chest in the shade. Velocities were measured in feet per second using a P.A.C.T. MKIV timer/chronograph with MKV skyscreens set 24.0 inches apart and the start screen 8.0 feet from the muzzle (P.A.C.T., Dept. SAR, P.O. Box 531525, Grand Prairie, TX 75053, 214-641-0049). The ambient temperature during the testing was 80°F (27°C) and the speed of sound was 1,139 fps (347 mps).
An unsuppressed Ruger 10/22 with factory barrel produced a sound pressure level (SPL) of 141 decibels with Remington high velocity LR ammunition, 139 dB with Remington standard velocity target LR, and 137 dB with Remington subsonic LR. The Model .22 IBS suppressed barrel produced an SPL of 124 dB with high velocity ammo, 121 dB with standard velocity target, and 115 dB with subsonic ammo. These represent net sound reductions of 17, 18, and 22 dB, respectively. By way of comparison, my pet Baikal Classic muzzle can from Sound Technology produced suppressed sound signatures of 122 dB with high velocity, 118 dB with standard velocity target, and 117 dB with subsonic ammo. Clearly, STW’s Model .22 IBS system delivers solid sound reduction.
In terms of muzzle velocity, all high velocity rounds out of STW’s IBS system were supersonic and the standard velocity rounds were transonic. Specifically, the unsuppressed Ruger factory barrel produced an average muzzle velocity of 1,227 fps with Remington high velocity LR ammunition, 1,119 with standard velocity, and 976 fps with subsonic ammunition. The Model .22 IBS system delivered muzzle velocities of 1,208 fps with high velocity, 1,098 fps with standard velocity, and 991 fps with subsonic ammo. About 40 percent of the standard velocity rounds produced a ballistic crack out of the IBS system on this particular day. The subsonic rounds delivered a very quiet, stealthy, and satisfying sound signature that was just 6 decibels above action noise. The dominant sound using subsonic ammunition was the bullet strike downrange.
STW’s Model .22 IBS system is particularly attractive for hunting and animal control, since it delivers excellent projectile velocity with all rounds. It has superior visual stealth to an integrally suppressed rifle with a 1.0 inch (2.5 cm) suppressor tube, it does not require a modified stock (if designed for a target-weight barrel), and it delivers nearly the same punch as a factory-original barrel. One can use high velocity ammo for maximum penetration or economy, standard velocity fodder for maximum accuracy and good penetration, or subsonic ammo when maximum stealth is required.
STW’s IBS system combines outstanding engineering with museum-grade workmanship and attention to minor details for the serious shooter. This is the sort of system that will endure a great deal of hard use, so I intend to add an IBS system to my outstanding Norrell select-fire Ruger 10/22.
Suppressed Tactical Weapons offers suppressed stainless steel Butler Creek barrels for the Ruger 10/22 with any overall barrel length up to 20 inches (50.8 cm). The retail price is $795. STW will also install a suppression module in a customer-supplied, target-weight, unfluted barrel for $695 retail. Only stainless steel barrels should be used with STW’s IBS system since moisture generated by powder combustion could corrode the counterbored, internally threaded barrels unless they are made from stainless steel. This robust titanium sound suppressor should give several lifetimes of workman-like performance, and its museum-grade craftsmanship should make it a valued family heirloom for generations. STW’s Model .22 IBS sound suppressor is a class act. For more information, contact Suppressed Tactical Weapons, Inc. (Dept. SAR, 6911 Bill Poole Road, Rougemont, NC 27572; phone 919-471-6778; fax 919-471-3314; e-mail raymonda@earthlink.net).
| This article first appeared in Small Arms Review V3N8 (May 2000) |
