Today I got a chance to get to the range.  I only had about an hour so I only took my two newly acquired rifles.  A SA M1 Garand and a CETME (CAI on SW receiver).

I loaded a clip into the M1, closed the bolt, took aim, squeezed the trigger............and click.  I cycled the round out and examined it. It had a light primer strike. I then let the bolt come forward, chambering an other round, squeezed the trigger and then........click.  This round had no primer strike.  I then took out the bolt and found that the firing pin had broken where hammer strikes it.  I have a complete Beretta parts kit, so I will steal a firing pin from it and get a replacement on order.

I also found out today, I do not like the CETME.  sights suck (my glasses hit the top of the receiver when sighting), the charging handle is to far forward, and it shoots a foot high.  I can correct the elevation problem, but not the other two problems.  IMHO I can not see all the rage over the HK type rifle????  Maybe a real HK is better, my CETME is a typical CAI product.  I guess I will put the CETME in the back of my safe or maybe trade it off.  It doesn't hold a candle to my FAL.

I feel the CETME is a total loss.  The M1 just needs the bugs worked out of it.

OSA

Sorry about your luck with the garand.

I will say that I hate the sights on the HK rifles.IMO

It seem that a tool is needed to change the firing pin??  I do have a spare complete SA bolt from my parts kit.  How critical is head space in this rifle?  

OSA

Disassembly of a Garand bolt can be so rewarding!  Seriously, it is difficult if not done properly, as the result can be small spring loaded parts rocketing off into the sunset.  The easiest way is to use a proper bolt disassembly tool.  I have done it with a small piece of brass, a vice, and a small flat head screw driver.  First attempt resulted in ordering some replacement parts.  I would not recommend trying it yourself without the proper tool.

An easy way to check head space is to install the new bolt, insert a cartridge, and chamber the round.  The bolt should close properly and be all the way down.  I have done this and it has worked in the past.  Here is the warning though, THIS MAY NOT BE GOOD ENOUGH to prevent problems, the best way is to use a proper gauge.

Hey, my worst day at the range was still way better than my best day at work.

Wow, I have never had the pleasure of breaking a Garand firing pin.  I just break extractors.

At least you got to go.
I cut firewood.
Good luck. I hope that you can get the problem taken care of.