Help with new to me Hammerli 215 - Is this a firing pin problem?

Recently purchased a Hammerli 215 on Gunbroker.  Really loving the gun, but once every 20 rounds or so I think I'm getting light strikes on the round because it chambers but does not ignite when I pull the trigger.  If I extract and then re-chamber the round it does go off.

So far it's happened with 2 different brands of ammo, so I don't think it's ammo related.  When I extract the unfired casing, it does a have an indentation on the side of the round, so the firing pin is hitting it, but maybe with not enough force/light strike.  

Do I need to replace the firing pin, or is this something else?  Maybe the gun isn't fully in battery?

pull off the slide. look at breech face and see if you can pick any build-up off the edges/corners. push firing pin from rear/out so you can see the tip. see if tip is firm or floppy. floppy indicates it could be broken. clean chamber really good.
shoot it again and hopefully all is well.
jon

Also look at a new recoil spring. Seen it be a  issue on the trailside which is the cheap cousin to the 208/215 series

With the slide off, look really closely at the rear of the pin where the hammer hits it.  If it is mushroomed or enlarged looking, it could be a soft pin.  A bunch of years ago some mis-tempered pins made it to the market.  While you're looking there press the firing pin in and let it return.  If the pin returns, but the tip stays sticking out, it is broken.

Also, do a "plunk" test: With the slide off the gun, you should be able to drop a round into the chamber and have it fully seat.  Then it should fall out when inverted.  The seating is more important and different bullet/lubes will also affect this test.

The mainspring may also be an issue.

1st and easiest thing to look at is recoil spring. Check if slide is fully closing each time. Once in 20 means you need to check 20 times to spot this. If it is not fully closing the inertia from the hammer will drop a pin on the primer but not hard enough to ignite as half of the inertia will be used to close the slide all the way forward at the same time. Seen this on 215 and SW 41.

Gunk and buildup will act same way.

What everyone else said.  You could have multiple issues going on.  I had a 208S with a soft firing pin, Ed Hall helped with identifying this issue.  The recoil spring was a little weak.  Lastly, my gun was a laser with Eley ammo.  But the chamber had to be cleaned every 20-30 rounds to keep it from doing what you described above.

Thanks, very helpful comments.  Really hoping I'm not going to have to clean the chamber every 20 rounds.

the manual states, remove the wax from the bullet before loading magazine.