You're really asking about a lot of different things here.


Joining the service might get you training as an armorer on a handful of weapons, but more than likely not as a gunsmith.

To get a career as a small arms designer, you'd probably want to start with a degree in mechanical engineering.

A novice wanting to get started as a hobby gunsmith would be well served by doing some reading on whatever specifics they wanted to start with: http://www.brownells.com/.aspx/cid=10009/Products/Books-Videos

Someone wanting to make a more serious step into becoming a professional gunsmith would probably be best off by researching and attending one of the better gunsmithing schools out there.

Colorado School of Trades
1575 Hoyt Street
Lakewood, CO 80215
Contact: Gary Schlomer
Phone: 303-233-4697 ext. 42
Email: gary@schooloftrades.com

Lassen Community College
478-200 Hwy 139
Susanville, CA 96130
Contact: John Martin or Steve Taylor
Phone: 530-251-8800
Email: staylor@lassencollege.edu

Modern Gun School
80 North Main Street
P.O. Box 846
St. Albans, VT 05478
Contact: Janie Gregory-Hilliker
Phone: 800-493-4114
Email: janieg@dlilearn.com

Montgomery Community College
1011 Page Street
P.O. Box 787
Troy, NC 27371
Contact: Wayne Bernauer
Phone: 910-576-6222 ext. 234
Email: bernauerw@montgomery.edu

Murray State College
One Murray Campus
Tishomingo, OK 73460
Contact: Dean Arnold
Phone: 580-371-2371 ext. 235
Email: darnold@mscok.edu

Pennsylvania Gunsmith School
812 Ohio River Blvd.
Avalon, PA 15202
Contact: Bob Thacker
Phone: 412-766-1812
Email: bob.thacker@pagunsmith.edu

Piedmont Technical College
620 Emerald Rd North
PO Box 1467
Greenwood, SC 29646
Contact: David Berryhill, Gunsmithing Program Coordinator
Phone: 864-941-8753
Email: berryhill.d@ptc.edu

Pine Technical Institute
900 4th St. S.E.
Pine City, MN 55063
Contact: Dave Defenbaugh
Phone: 320-629-5157
Email: Defenbaughd@pinetech.edu

Sonoran Desert Institute
10245 East Via Linda, Suite 110
Scottsdale, AZ 85258
Contact: Toni Pino
Phone: 480-314-2102 Ext. 201
Email: info@sonoranlearning.com

Trinidad State Jr. College
600 Prospect
Trinidad, CO 81082
Contact: Keith Gipson or Dave Nolan
Phone: 719-846- 5577
Email: keith.gipson@trinidadstate.edu

Yavapai College
1100 East Sheldon Street
Prescott, AZ 86301
Contact: Alan Lohr
Phone: 928-776-2348
Email: alan_lohr@yc.edu 

Thanks for the info Jesse. I've been considering gunsmithing after I retire. Troy, NC, and Greenwood, SC, are close enough to buzz back home on the weekends.

I've been very slowly teaching myself and learning from people I know.

You start with basic tools, like those used for building AR-15's. Then you find a job that requires removal of metal. So you grab the dremel. Shortly afterwards, you log onto Brownell's and order a replacement part or two and a set of stones. A few weeks later, you repeat, and work a little slower, and get much more positive work done before once again logging onto Brownell's and, this time, ordering three of the part.

After a few months of this, you have successfully done what you wanted to do, and have a huge pile of worthless parts, but realize that in order to get that trigger juuussst right you need to replace a different part. This time you work slowly from the beginning, but after an hour trying to fit a trigger with very fine stones, you get bored and break out the Dremel.... Repeat the first paragraph.

I was incredibly fortunate to have a grandfather who was a professional gunsmith. I spent many hours in his shop as a kid picking up what I could. He later sold the business but he kept the equipment and tooling, which I've inherited since he passed away.

I didn't learn near enough as a kid to be a competent gunsmith, but having all the tooling and library of gunsmithing books along with a number of unfinished projects has given me a bit of a leg up in edjamacating myself.

I've been doing much, MUCH better work since my dremel broke...
 

The guy teaching my AR armorer class said Dremels ought to require a background check, fingerprinting, a Class 3 tax stamp and a 1 year waiting period and that if any of us were carrying Dremels concealed in ankle holsters, we needed to take them back out to the car or get kicked out of class. 

I don't understand anti-Dremel elitists and Fudds who think abrasives should only be applied slowly, by hand.

I do. It doesnt take much of a slip to mark up a receiver really bad, and even less of one to make a sear unusable. I think that after the 10th or 20th time someone brings you something to fix after they "tried to do it themselves" that the attitude can develop.

Dremels have their place and are an indespencible tool, but when used in the wrong hands they create more problems than they fix.

I do. It doesnt take much of a slip to mark up a receiver really bad, and even less of one to make a sear unusable. I think that after the 10th or 20th time someone brings you something to fix after they "tried to do it themselves" that the attitude can develop.

Dremels have their place and are an indespencible tool, but when used in the wrong hands they create more problems than they fix.

I was joking around...

Dunno if it constitutes gunsmithing, but I'm in the middle of my first AR project and successfully installed the trigger guard without breaking the ears off the receiver. Can't wait to assemble the upper.

 
That's how a lot of folks start out. That's where I started meddling with the innerds of guns. It's a fairly plug-n-play way of learning how the hidden mechanics of a firearm work. Many of the same principles translate to other firearms. At least to me, they do.

Revolvers, however, operate on PFM as far as I can tell.