There is way too much information missing from the question to even guess at an answer.

There is far more to ignition reliability than firing pin diameter.

- radius of firing pin nose
- weight of firing pin
- length of firing pin (at both ends)
- firing pin travel distance
- hammer impulse (itself a function of mainspring stored potential energy, hammer weight, pivot location, travel distance - A.K.A. moment of inertia)
- headspace

The reality is that there is likely no answer to your question. Given all of the variables in construction just between primer brands, what works for one may not work for another.
Some of those variables are:

- primer cup hardness
- anvil design
- priming compound sensitivity

Has the rifle always suffered ignition reliability problems?
How far is "slightly off center"?