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Locksmithing/Mosler Vault in National Guard Armory


QUESTION: I have a Mosler vault door in my armory. I have the combination and I know how to get in and out of the vault.  There is an annual requirement to change the combination.  I have no clue where to start with that process.  There is a small key hanging on the door.  I'm assuming that might have something to do with changing the combination.  There are at least 6 other vault doors that need the combinations changed.  If I can learn, I can help my co workers.  Any asistance would be greatly appreciated.

ANSWER: Gabriel,

I never recommend combination changing as a DIY project for the same reason that I never recommend using locksmiths.   Lack of training, knowledge and tools can result in an expensive lockout.  As a former Army officer (retired), I do understand the way the Army and National Guard require combinations to changed by the person in charge of the safe or vault - unfortunately, as with most items that really count, the military doesn't provide adequate training.   Instead they focus on items that basically waste our time.

I do recommend that you get the necessary training to change combinations so that you are proficient in doing it, and/or can show others who are in responsible positions and may have to change their combination as well.

If you don't have a local safe company that you can use for combination changes, I would be happy to provide you with a set of basic changing instructions, with the caveat that YOU understand that you assume all responsibility for ensuring that the lock works correctly BEFORE closing and locking any safe or vault door.    My basic training class is about 1 week long, so I'm not going to be able to train you in an email.

I'll need you to send an email directly to me so that I have somewhere to send the instructions to (bounce email).    As they will be coming as a PDF file, I will need an email address that won't see the email as "spam".

I will also need to know what lock you are dealing with, so that I can provide you with the correct instructions.   I would suppose that the lock is either a Mosler MR302, or an S&G 8500 series lock, or possibly the new S&G 2937.

I would recommend that you contact the DOD lock program to find about any available training programs at:
this is also a great website to stay in contact with for security updates and any resources.   you may be able to get proper or correct instructions for your lock from them as well.

Currently DOD lock training has been "temporarily" suspended but I would still recommend contacting them for current updates, and/or dates of opportunity training.    They can help facilitate training (or at least point you in the right direction) for ALL of the locks that are currently authorized for use by DOD services.

Hope this helps.   Thanks for your service.

---------- FOLLOW-UP ----------

QUESTION: Mr. Anderson,

I looked up the link you sent me.  I submitted a help ticket.  I recieved a response.  Now I am just waiting on the instructions to be sent to me.  Thanks for the help.


If you are going to be working with the safe locks for your unit, changing combinations or potentially teaching others how to do the work, I would recommend that you either stay in touch with the DOD Lock Program, or request to be added to their email listing.    They send out several informational emails during the year with good info, and updates on security requirements.

Also check out their "Security Facts Newsletter".   They have a lot of the past issues on their site, containing a lot of good info.

This is a great resource if you are working as the security officer or NCO for your BN or Company.

Glad to be of help.


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Terry V. Andreasen (Andy)


Safe and Vault related Questions; Antique Safe Repair and Restoration; With over 42 years in the Safe & Vault industry, if I can't answer your question I know where to get the answer. Current Project: Restoration of an Ely Norris Cannonball Safe from the early 1900's. Will answer Safe & Vault related questions concerning age, value, restoration, moving, opening & repairing, parts, operation and history. Note: It is not my intention to teach you to open safes or to provide information which may aid in the unlawful opening of a safe. I will not give out drill points or information which I deem inappropriate.


44 years in the Safe & Vault Industry. Owner and Service Manager for one of the largest Safe & Vault companies on the West Coast. Graduate of Lockmasters Safe Lock Servicing, Safe lock Manipulation and Safe Deposit Lock Courses. Graduate of Locksmith Institute. Certified Instructor for the California Locksmith Association teaching Basic and Advanced Lock Servicing, Basic Safe opening and Repairing. Factory Trained by AMSEC, LORD Safes, LeFebure, Mosler, KabaMas, LaGard and Sargent & Greenleaf Author of "The Coffee Table Guide to Antique Safes".

SafeCrackers International and the National Antique Safe Association Safe & Vault Technicians Association (SAVTA)

The Coffee Table Guide to Antique Safes

Graduate of Locksmith Institute 1972 Graduate Lockmasters Safe Lock Servicing 1974 Graduate Lockmasters Safe Lock Manipulation 1975 Graduate Lockmasters Safe Deposit Lock Servicing 1985 Instructor Certified - California Locksmith Association - 1985 Factory trained by AMSEC, MAJOR, STAR, Johnson-Pacific, Kaba-MAS, Allied-Gary, ISM, Lord, Brown Safe, EXL, Mosler, Diebold.

Awards and Honors
2009 - 2015 - Listed in AllExperts Top 50 Experts. All Expert Categories - Safes & Security Containers, Locksmithing, Antique Safes. Retired US Army Chief Warrant Officer (CW4), with 39 years of total service. With numerous awards from Vietnam, Desert Storm and Operation Iraqi Freedom. US Navy - 1971-1981 US Army Reserve 1984-2013 US Army Retired

Past/Present Clients
US Secret Service, FBI, BATF, Local Law enforcment agencies, Diebold, Hamilton Pacific, Red Hawk Int., Chubb International, Bank of America, Wells Fargo Bank, Mechanics Bank, El Dorado Savings Bank, many Credit unions and smaller banks. McDonalds, Togos, BurgerKing, TacoBell, Carls Jr. FoodMaxx, SaveMart, Lucky's, Albertson's, Raley's, Safeway, NobHill, Bell Markets, PW Markets. Great America, Century Theatres, Cinemark Theatres, UA Cinemas, and many homeowners and small businesses. Provide warranty service for lock and safe manufactures. Service Area is Northern California (Fresno to Oregon and Western Nevada)

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