I picked up a police trade in gen 3 Glock 27 a while back.  There was enough rust on the recoil spring that I replaced it with a new stock recoil spring assembly.  

Today is the first time I have fired it.  100 rounds 165 gr american eagle and 50 rounds 165 gr HST.

There were three failures to fire (1 american eagle, 2 HST) which I though were light primer strikes, but now it looks like the firing pin hit toward the edge of the striker.

Is the firing pin striking the primer normally?  If not, why would it be off center?

Is the firing pin not hitting the primer hard enough?  I so, would I just need a new firing pin spring?

Pic of primers

Doesn't look like other Glock primer strikes I have seen.

Since its a trade in, hard to know ANYTHING about the gun.  I would replace every spring in the gun.  Also, post a picture of the tip of the striker.

Good point, I have no idea what was done to it in the past.

Pic of striker tip

Contact Glock they will probably have you send it in and upgrade the internals.  

Off center strikes usually mean the slide is just a hair out of battery when the striker releases, which most times is a bad rsa but you already addressed that. A trip to glock for rebuild may be in order. Another option is to go to a gssf match in your area where the armorer on hand will inspect and repair your gun for free while you wait

I agree but you need to inspect and clean the striker channel in the slide.  If the channel is dirty it can inhibit the pistol from firing.  Glock teaches to clean the slide with the breach face down to limit fluid and gunk from getting into the firing pin channel. While I had the striker out I'd replace the striker spring and inspect the firing pin block.   It was a good recommendation to replace all the springs.

Thank you all for the replies.  I think I'll talk with Glock customer service and have them take a look at it.