There are two types of police armorers: sworn and unsworn. The latter is a civilian who is tasked with servicing his/her department's firearms, the records, supplies, etc. Some agencies even have that person serve as a firearms instructor. The CA Highway Patrol and the Royal Canadian Mounted Police are two agencies that go that route (note: CHP uses sworn personnel for firearms instructors).
The other route of course is that all the work described above is done by sworn personnel. It's not easy to land a job like that since officers vy for "cherry positions." You have to be liked, connected, or, having the skills already, be in the right place at the right time. The job may not even full time (especially if it's a smaller agency) and the armorer may be expected to pull his share of grunt work. Some agencies may not even help with training and the individual must use their own funds to pay tuition/fees.
If you're really interested, shop for agencies which take unsworn personnel. The CHP wanted and seeks gunsmiths who have formal training (college certificate). In your case, if you prove that your MOS (2112?) includes operation of a lathe and milling machine, welding, plus extensive experience (take your photos of completed work and you at your workbench now), they may waive the educational requirements.
bobo's comment that gunsmiths are more qualified than armorers is generally true. However, military armorers (especially the ones for the service branch's shooting team) are as good if not better than many gunsmiths. The same applies for the Brit's Royal Army Mechanical Engineers (Armorers) who serve a four year apprenticeship.
So 45b, don't just dream it. Get all the training and experience you can now while in the service. Then go out and do it! Heck, my agency lets me and it took years.
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