Low Back Pressure Gas Gun SuppressorExtreme Duty/Full-Auto, 5.56mm
The SPIRO is a low back-pressure gas-gun suppressor that has excellent sound suppression levels at both the muzzle and at the shooter's ear.
You no longer must compromise and have your gas gun suppressor be "Low back pressure but loud at the muzzle."
The SPIRO increases back-pressure gas flow by only approximately 50% compared to a bare muzzle (most LBP are 35-85%), which is 3X less gas than a Dominus-SR. The SPIRO only increases the cyclic rate of an Mk18 by about 5% (compared to 43% for a Dominus-SR; most LBP 3%-10%). This is while keeping Shooter's Ear peak dBA at 136.8 (LEq dBA 124.2), and milspec-left muzzle position 135.4 dBA (LEq dBA 122.5). For reference, the Dominus is a few dB louder at the milspec position and at the shooter's ear.
Spiro Comparative Perfomance Data Table
Suppressor
Bare Muzzle
TBAC Spiro DT
TBAC Dominus CB
Competitor 1
Competitor 2
Competitor 3
Competitor 4
Length (in) **
5.9"
6.95"
5.5"
6.5"
6.8"
7.0"
Weight (oz) **
15.5
13.58
15.57
19.26
22.73
21.87
Shooter's Ear Peak dBA
159.8
136.8
137.8
140.1
137.6
138.2
138.9
Shooter's Ear LEQ dBA
144.7
124.2
126.1
128.0
127.0
125.6
126.6
Mil Spec Peak dBA
167.2
135.4
137.9
149.5
138.8
143.8
137.1
Mil Spec LEQ dBA
149.1
122.5
125.8
132.8
125.5
127.4
124.0
Backpressure psi*ms (% increase)
511
765 (50%)
2361 (362%)
754 (48%)
1801 (252%)
710 (39%)
839 (64%)
Cyclic Rate (% increase)
601
632 (5%)
857 (43%)
619 (3%)
787 (31%)
650 (8%)
623 (4%)
*Data obtained from a 10.5" AR-15 with fixed gas block and M193 ammunition
*Backpressure data obtained via TBAC backpressure standard
**As tested including any adapters i.e. HUB to 1/2-28
From the table, the SPIRO eclipses popular "low back pressure" suppressors in terms of muzzle and shooter's ear suppression levels, when considered together. It does this while only adding approximately 5.3" to the overall weapon length.
It is a "Go To War" suppressor designed for 10.5", 5.56mm caliber assault rifles. It works great on .223 / 5.56mm caliber gas guns from 8" up to 16" or longer. The SPIRO is designed to be put on your 5.56mm carbine and shot a lot, only being removed for firearm maintenance and suppressor cleaning.
The SPIRO is made from Haynes 282, a nickel-chromium-cobalt-molybdenum "Super Alloy." It is stronger than Inconel 718 and exceeds Inconel's operating temperatures by about 500 degrees F. This makes the SPIRO almost indestructible. While our other "full auto rated" suppressors are guaranteed to last 10 cycles of the 8-mag SOCOM SURG test on a 10.5" barrel, the SPIRO is rated for over 20 of the same cycles using an 8" barrel instead of a 10.5".
People have been talking about "low back pressure" for a while, but there hasn't been an objective method to actually quantify it. Thunder Beast Arms Corporation wasn't satisfied with that, so they invented the TBAC Method of Measuring Back Pressure, and then we used the same sound-test setup we use at the SILENCER SUMMIT to make a very low-back-pressure suppressor that is also unbelievably quiet at both the muzzle and at the shooter's ear, for a suppressor under 6".
SUPPRESSOR DURABILITY RATINGSThere is general confusion about which firing schedules different suppressors on the market can withstand. Thunder Beast has seen "full auto"-rated suppressors that will fall apart after a few mags of full auto, and on the other hand, there are some "precision rifle suppressors" that will actually withstand a lot of abuse.
TBAC rates their suppressors conservatively and tries to be as accurate as possible in their descriptions of the uses they can withstand "forever" or for their defined service life. To this end, they have defined the following firing-schedule categories for Thunder Beast centerfire rifle suppressors.
SPIRO CATEGORY: "HARD-USE/FULL-AUTO MOD 1" [HU/FA/1]Lifetime to exceed at least 20 SURG cycles on a 8.0" "Mk18 Style AR".Note that the upper and muzzle devices will likely not survive this entire trial.
One SOCOM/SURG CYCLE comprises:
Mag 1: 1 round/second
Mag 2: 2 rounds/second
Mag 3: 1 round/second
Mag 4: 3-5 round burst
Mag 5: 1 round/second
Mag 6: 2 rounds/second
Mag 7: 1 round/second
Mag 8: 1 continuous burst
Outlined in Section 3.6.1.i. in Solicitation H92222-17-R-0011
The basis for this is the SOCOM/SURG specification, which is a common heavy firing schedule specified in many military solicitations. TBAC's SURG cycle consists of 8 magazines (30-round magazines) fired in this pattern, with magazine changes as quick as possible. After a full 8-magazine cycle, the suppressor and firearm is allowed to cool to ambient. This firing schedule significantly exceeds the worst-case application of assault rifles and battle rifles. A milspec M4 needs service and inspection after each cycle to keep operating.
Suppressors in this category will still have minimum barrel length ratings for most cartridges.
Specifications:
Maximum rated caliber: .223/5.56mm caliber, .22 Creedmoor
Material: Haynes 282
Length: 5.9 inches
Length added: 5.3 inches (DT)
Diameter: 1.8-inch OD
Mounts: HUB (1.6" from TE to first baffle)
no mount included with HUB version
Weight: 15.5 ounces
Finish: Black CeraKote
Brake Material: Haynes 282
Use: Gas Guns / Hard-Use/Full-Auto
Warranty TBAC Limited Lifetime Warranty
Minimum barrel lengths:
"any" 4.6x30 HK, 5.7 FN
8" .223, 5.56mm, 5.45 Russian
12.5" 22 ARC, 224 Valkyrie
18.0" .22-250, 22 Creedmoor
Once your suppressor purchase is finalized with Mile High Shooting, a Form 3 will be filed with the ATF requesting approval to transfer your suppressor to your chosen FFL. Initial processing can take 3-7 business days. Customers may help expedite this time frame by requesting the chosen FFL to send a copy of their FFL & SOT to ffl@milehighshooting.com. Please note, initial processing time may be delayed further if your chosen FFL fails to provide required documentation in a timely manner. Once submitted, it takes 7-21 days for Mile High Shooting to receive the Form 3 approval. As soon as the approval is received, your suppressor and any accessories will be shipped to your chosen FFL within 24-48 business hours by 2 Day Air. Your chosen FFL will then contact you once it is received and you may complete your Form 4 processing at their facility.
___LEGAL INFO______
Mile High Shooting Accessories (MHSA) will only ship suppressors to Class III FFL holders. BATF regulation information for Suppressor ownership are as follows:
Be at least 21 years of age. Be a U.S. citizen. Have no felony convictions or domestic violence convictions. Have no dishonorable discharge. Not deemed mentally unstable by a competent authority. The NFA rules/laws are posted through the BATF website. At this time, the following states DO NOT ALLOW private ownership of suppressors: CA, MA, DE, HI, NJ, NY, RI, IL, District of Columbia. CA allows class 3 dealers and class two manufacturers to possess suppressors.
U.S. Government Export Restriction
This item is restricted for export by the State Department and Department of Commerce. Make sure that you are familiar with all applicable laws. ITAR Information.
FFL Requirements & Magazine Restrictions
This item has to ship to an FFL. Please read the attached information. Shipping Rules & Magazine Restrictions.
About Mile High Shooting:
Mile High Shooting Accessories has over 40 years of experience in the retail and sports shooting industries. Mile High is the world's largest stocking distributor of Accuracy International and Spuhr, also stocking lines such as Thunder Beast, Nightforce, Swarovski, Vortex, Zero Compromise Optic (ZCO), Zeiss, Hornady and many more! We pride ourselves on stocking the best brands in the industry. We are proud to be veteran-owned, Woman-founded, offer industry-leading service, and run our business with integrity!
Visit Product PagePhone:
3032559999
Location:
5831 Ideal Drive,
Frederick
Colorado
80516
