I highly recommend fully reading through the following link.
Most of the research on hyper velocity impacts looks at objects traveling at about half your projectile speed because about 15km/s is the most we expect to need to worry about in regards to small debris.
However, Whipple Shielding is highly effective at stopping small impactors at hyper velocities. If you look at figure 4-2 at that page, you will see that the effectiveness of the Whipple shielding on the ISS drops off at higher velocities, but should still be at about half effective at the speeds we are talking about (also, what might be important for story purposes, Whipple shielding is actually shockingly ineffective against projectiles at around 2km/s (though more traditional shielding is usually behind the Whipple shielding).
Impacts against Whipple shielding will produce clouds of plasma as the impact material (and shielding) disintegrate. While this won't cause damage, but it can mess with electronics.
Something important to note about this. Whipple shielding testing is done with Aluminum spheres with a diameter between .5-2 cm. Larger projectiles have more energy (though only linear, unlike the quadratic increase from velocity).
This video shows the impact of a small (4mm) hyper velocity projectile hitting a non-pressurized tank in a vacuum. You can see the blast of plasma and shrapnel that fly out.
The wikipedia page for Hypervelocity has a pic of more traditional shielding. For reference it is 18 cm thick and the projectile is 1.2 cm.
High velocity impacts cause the materials to behave as fluids because materials can behave like fluids under high stress. This page has some useful areas showing you what damage can occur even when not catastrophic.
You can end up with what is called "detatched spalls." Internal fracturing of the material could cause shrapnel even if the material itself was not penetrated.
Here you can read more about the materials used in shielding, and this will let you compare different shielding styles (Whipple is just what is used on the ISS).
This paper includes some useful graphs that you can use to extrapolate penetration depth.
But what will happen with a larger projectile. NASA and the ESA quote "catastrophic failure" for 10cm projectiles. But what happens to the projectile.
Unfortunately your question falls outside of what people typically will test. Spacecraft shielding typically is tested against small impactors. Larger impactors tend to be tested against rock (for cratering of moons).
I am assuming your projectiles are going to be larger than 10cm?
I can say for certain it won't be fully intact. You will get some plasma and some shrapnel. Will your projectile continue in to impact more things? It's hard to say without knowing more.
If you give me an approximate projectile size and armor thickness, I can run a simulation for you and get back to you with "nice" pictures and edit my question, but with the details as given I think my answer is suitable.
If you want to run the simulation yourself, I would recommend gizmo. Actually iSale would be even better / easier. One of their examples is exactly what you need as long as you tweak the projectile size and speed. However, you would need to contact them to get permission to run it.