HM Defense Stealth 556

	A	B	C	D	E	F	G
1	Location:	Middle GA			Weather:
2	Date:	09/08/2022			Temp (°F)	76.2
3	Time:	12:03 PM			Humidity	76%
4	Elevation:	736 ft			Pressure (Hg)	29.15
5					Wind:	1.2mph @ 189°
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8	HM Defense STEALTH 556 Integral Upper				Unsuppressed	Muzzle	Right Ear
9	Federal M855 Ball					N/A	N/A
10	Silencer	Muzzle	NSR	FRP	Right Ear	NSR	FRP
11	HM Stealth 556	141.9	N/A	0.5	143.1	N/A	-2.3
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14	NSR = Net Sound Reduction
15	FRP = First Round Pop
16	SPL = Sound Pressure Level
17	OBA = Octave Band Analyzer
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19	All official testing conducted per MIL-STD 1474 D specifications using a Bruel & Kjaer 2209, A-weighted
20	Open field with no sound reflective surface within 10m of 4136 pressure mic
21	Muzzle measurements 1.6m high, 1m left of exit aperture
22	Right ear measurements taken 30cm from front of ejection port, 8cm high and 15cm right of bore centerline
23	Frequency Analysis Data (if applicable) collected using Larson Davis LxT Octave Band Analyzer, Normal Range, A-Weighted, single shot with two second total meter runtime
24	OBA curve charted to match average SPL from 2209 at each metering postition, provides visual representation of the tonal signature of silencers/moderators tested
25	Meters calibrated prior to and after testing using a Larson Davis CAL-200 at 94dB & 114dB with <.05dB variance
26	Weather data collected using Kestrel 5700 Elite Onsite
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