Bullet Penetration Demonstration Fact Sheet
Presented by Bill Hutson - City of Boulder, Facilities Coordinator
In Attendance
William Boyes - City of Boulder, Facilities Manager
Eric Harris - City of Boulder, Assistant Personnel Director/Safety Officer
James Tydings - City of Boulder, Assistant City Attorney/Risk Manager
Wendy Testa - City of Boulder, Facilities Coordinator
Gary Mancuso - General Contractor - Lone Wolf, Inc. (Louisville Colorado)
& Energy Concepts, Inc. (Jamestown Colorado)
The purpose of this demonstration is to evaluate only one small aspect of the much more complex "security" issue, and is not meant to be a complete solution to the much broader issue. I intend to provide you with a fair sampling of building alternatives for protection against the use of firearms, in the hope that one will satisfy both sides of the protection versus costs issue, and will help us obtain a level of protection that is acceptable to staff while balancing that within a cost range that is not prohibitive.
This demonstration will provide you with a reasonably accurate representation of what might be expected of various building materials ability to withstand penetrations by a number of commonly used bullets.
For your convenience, I have attached a chart showing the cost per installed square foot of each of the assemblies we will be testing.
The firearms I am using have been selected based on press coverage of incidents around the nation, as weapons/calibers commonly used in attacks on citizens. These range from what are commonly referred to as "plinking" to "big game" calibers.
There are several commercially available products that are designed to resist bullet penetration ranging from polycarbonate to ballistic fiberglass and Kevlar. I have specifically excluded Kevlar as its cost is at least three times that of the next most expensive product we have here today.
We also have the option of using steel plate as we installed in our City Hall lobby, and we will demonstrate on a sample today, however, it is extremely difficult to work with and the necessity for welding inside occupied offices presents its own hazards.
In this demonstration we will include a normal or standard wall, the type that the majority of which all our offices are constructed, as well as several derivations and some commercially available products.
I will fire a single round of a given caliber at each wall, and after I determine the range is safe we will perform a brief evaluation, then we will repeat with each of the calibers I have provided. My hope is that we will be able to come to some consensus of cost versus benefit.
You will each be required to wear eye and hearing protection during the tests or wait in a vehicle until I give the "range clear" command.
| Material Cost | Labor Cost | |
| 5/8" Gypsum on 2"X4" studs (standard wall) | $ 0.30 / sf | $ 1.63 / sf |
| 5/8" Gypsum on 2"X4" studs with 1" OSB both sides with concrete poured in between | $ 1.06 / sf | $ 2.04 / sf |
| 5/8" Gypsum on 2"X4" studs with 1/4" steel plate in between | $ 7.50 / sf | $ 4.41 / sf |
| 5/8" Gypsum on ½" Polycarbonate | $ 3.95 / sf | $ 3.85 / sf |
| 5/8" Gypsum on Level I ballistic fiberglass | $ 19.00 / sf | $ 3.27 / sf |
| 5/8" Gypsum on Level II ballistic fiberglass | $ 33.86 / sf | $ 3.71 / sf |
| 5/8" Gypsum on Level III ballistic fiberglass | $ 48.33 / sf | $ 4.14 / sf |
| 5/8" Gypsum on Level IV ballistic fiberglass | $ 108.14 / sf | $ 5.27 / sf |
OSB - oriented strand board
sf - square foot
Gypsum - drywall
| RESULTS | ||
| Calibers Used | Calibers That Penetrated |
|
| 5/8" Gypsum on 2"X4" studs (standard wall) | .22 12 ga #4 shot |
.22 12 ga #4 shot |
| 5/8" Gypsum on 2"X4" studs with sand filled | .22 9mm 12 ga #4 shot |
.22 9mm 12 ga #4 shot |
| 5/8" Gypsum on 2"X4" studs with 1/2" polycarbonate | 9mm .45 auto 12 ga #4 shot |
12 ga #4 shot |
| note: 12 gauge completely destroyed polycarbonate and pushed broken pieces 20 yards downrange | ||
| 5/8" Gypsum on 2"X4" studs with 2 layers of 1 1/8" OSB | 9mm .45 auto .357 12 ga slug |
.357 12 ga slug |
| 5/8" Gypsum on 2"X4" studs with 1/4" steel plate | .22 9mm .45 auto .357 .44 12 ga. Slug .223 .270 Win |
.223 .270 Win |
| 5/8" Gypsum on 2"X4" studs
with 1/2" plywood both sides and cavity filled with concrete |
9mm .45 auto .357 .44 12 ga. Slug .223 .270 Win |
|
| 5/8" Gypsum on 2"X4" studs
with 1 1/8" OSB both sides and cavity filled with concrete |
9mm .45 auto .357 .44 12 ga. Slug .223 .270 Win |
|
| 5/8" Gypsum on Level I ballistic fiberglass | .45 auto .357 |
|
| 5/8" Gypsum on Level II ballistic fiberglass | .44 | |
| 5/8" Gypsum on Level III ballistic fiberglass | .223 * | |
| 5/8" Gypsum on Level IV ballistic fiberglass | .270 Win | |
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* I fired 13 rounds of .223 into the same hole and there was no penetration |
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OSB - oriented strand board
sf - square foot
Gypsum - drywall
| All Targets Set At 7 Yards Downrange |
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| Targets Prior To Firing |
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| Targets After Firing (Steel #4 Shot, Lead 12 gauge Slug & All Others Jacketed Solid Points) |
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| Back of Targets After Firing |
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| Material Cost | Labor Cost | |
| 5/8" Gypsum on 2"X4" studs (standard wall) Typical office wall per lineal foot $ 15.44 Typical 42" front counter wall per lineal foot $ 6.76 |
$ 0.30 / sf |
$ 1.63 / sf |
| 5/8" Gypsum on 2"X4" studs with 1" OSB on both
sides Typical office wall per lineal foot $ 24.80 Typical 42" front counter wall per lineal foot $ 10.85 |
$ 1.06 / sf |
$ 2.04 / sf |
| 5/8" Gypsum on 2"X4" studs with 1-1/8" OSB on both sides and concrete filled Typical office wall per lineal foot Typical 42" counter wall per lineal foot |
$ 3.16 / sf | $ 2.87 / sf |
| 5/8" Gypsum on 2"X4" studs with 1-1/8" plywood on both sides and concrete filled Typical office wall per lineal foot $ 45.04 Typical 42" front counter wall per lineal foot $ 11.43 |
$ 2.76 / sf | $ 2.87 / sf |
| 5/8" Gypsum on 2"X4" studs with ½" steel plate in between Typical office wall per lineal foot $ 95.28 Typical 42" front counter wall per lineal foot $ 41.69 |
$ 7.50 / sf | $ 4.41 / sf |
| 5/8" Gypsum on ½" Polycarbonate Typical office wall per lineal foot $ 62.40 Typical 42" front counter wall per lineal foot $ 27.30 |
$ 3.95 / sf | $ 3.85 / sf |
| 5/8" Gypsum on Level I ballistic fiberglass Typical office wall per lineal foot $178.16 Typical 42" front counter wall per lineal foot $ 77.95 |
$ 19.00 / sf | $ 3.27 / sf |
| 5/8" Gypsum on Level II ballistic fiberglass Typical office wall per lineal foot $300.56 Typical 42" front counter wall per lineal foot $131.50 |
$ 33.86 / sf | $ 3.71 / sf |
| 5/8" Gypsum on Level III ballistic fiberglass Typical office wall per lineal foot $419.76 Typical 42" front counter wall per lineal foot $183.65 |
$ 48.33 / sf | $ 4.14 / sf |
| 5/8" Gypsum on Level IV ballistic fiberglass Typical office wall per lineal foot $907.28 Typical 42" front counter wall per lineal foot $396.94 |
$ 108.14 / sf | $ 5.27 / sf |
| OSB - oriented strand board sf - square foot Gypsum - drywall | ||
| Calibers Used | Calibers That Penetrated |
|
| 5/8" Gypsum on 2"X4" studs (standard wall) | 22 & 12 ga #4 shot |
.22 & 12 ga #4 shot |
| 5/8" Gypsum on 2"X4" studs with sand filled | .22 & 9mm 12 ga #4 shot |
.22 & 9mm 12 ga #4 shot |
| 5/8" Gypsum on 2"X4" studs with 1/2" polycarbonate |
9mm & .45 auto 12 ga #4 shot |
12 ga #4 shot |
| note: 12 gauge completely destroyed polycarbonate and pushed broken pieces 20 yards downrange | ||
| 5/8" Gypsum on 2"X4" studs with 2 layers of 1 1/8" OSB |
9mm & .45 auto .357 & 12 ga slug |
.357 & 12ga slug |
| 5/8" Gypsum on 2"X4" studs with 1/4" steel plate |
.22 9mm .45 auto .357 .44 12 ga. Slug .223 .270 Win |
.223 & .270 Win Mag |
| 5/8" Gypsum on 2"X4" studs with 1/2" plywood both sides and cavity filled with concrete |
9mm .45 auto .357 .44 12 ga. Slug .223 .270 Win |
None |
| 5/8" Gypsum on 2"X4" studs with 1 1/8" OSB both sides and cavity filled with concrete |
9mm .45 auto .357 .44 12 ga. Slug .223 .270 Win |
None |
| 5/8" Gypsum on Level I ballistic fiberglass | .45 auto & .357 | None |
| 5/8" Gypsum on Level II ballistic fiberglass | .44 | None |
| 5/8" Gypsum on Level III ballistic fiberglass | .223 | None |
| 5/8" Gypsum on Level IV ballistic fiberglass | .270 Winchester | None |
| note: After the test I fired 13 rounds of
.223 into the same hole on Level IV ballistic fiberglass and there were no penetrations |
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| OSB - oriented strand board sf - square foot Gypsum - drywall | ||
| Level | Typical Applications | Description |
| I | Most homes, small businesses As well as the majority of City of Boulder buildings |
Average/standard operations Complete access to buildings No special attention to security |
| II | A few City buildings and most public schools and universities |
Registered key systems Security lighting Employee training Safe areas plus Level I |
| III | Our City Police Dept | Restricted entries, computerized and monitored door entry systems plus Levels I and II |
| IV | Large Stores | Video systems, restricted entries plus Levels I-III |
| V | Courts, banks and large corporations | Metal detectors, armed guards plus Levels I-IV |
| VI | Rocky Flats, nuclear reactor plants and some large corporations, Las Vegas Casinos |
Psychological evaluation of Employees, background checks access granted to limited areas plus Levels I-V |
| VII | Cheyenne Mountain and Missile silos | Biological and bomb screening equipment including bomb and bullet proofing measures plus Levels I-VI |
| VIII | President of the United States | Employee armed or provided with armed security guards and bullet proof vehicles plus Levels I-VII |
| IX | Nuclear attack submarines and Russian Underground Plutonium Mines |
Employees, eat, sleep, work, live without ever leaving facility plus all previous levels |
Conclusion:
Based on these tests, it is my professional recommendation, when practical, that we utilize the combination of Oriented Strand Board (OSB) and concrete. For new construction this combination appears to offer the best results at a cost far less than the commercially available ballistic fiberglass. I would also recommend the use of the level I ballistic fiberglass underneath countertops as it is impractical to use concrete in these applications and the ballistic fiberglass is certainly the most appropriate when an existing area needs to be retrofitted with protection.
Personal Profile/Qualifications
40 year member of the National Rifle Association (NRA)
20 year member of the United States Practical Shooting Association (USPSA)
20 year member of the International Practical Shooting Confederation (IPSC)
Past president of the Boulder Practical Shooting Association
Certified Range Officer
Certified Course Designer
Reloader
Over 350,000 assorted rounds of ammunition fired
Performed various ballistic tests for Mike Walters (City of Boulder Police Armorer)
Performed various ballistic tests on glass assemblies for City of Boulder Housing Department)
Class A Licensed General Contactor
20 years as Facilities (Building) Coordinator for City of Boulder
