I'm a firm believer that salary potential is capped more by who you are than what qualifications you have. Qualifications may dictate average salary, but not max/potential. For example, most highschool dropouts have a very low salary; however, some are Walt Disney. So, keep in mind as you look at these figures that the best you can find is national averages. We can't really answer “how much can an accounting manager make”, just “how much does an accounting manager usually make”. And, the answer to that would depend on the size of the company and the number of duties in that position. I've seen Accounting Managers in larger companies with way more responsibility than Controllers like me in little companies, and I'm pretty sure their salaries are larger than mine as well. However, to try to share what I can…
In my opinion, having a CPA in private doesn't make you make any more money in a certain position (aka Senior Accountant); what a CPA does for you in private is open the door to a position that may make more. For example, a couple months ago I started a job as a Controller. I don't think that the fact I was a CPA made a big difference in what salary they offered me; however, I think it did make a big difference in determining whether I was ever even called in for an interview. So, I would presume that average salary of Senior Accountants at any given company is similar or the same regardless of CPA status, but I would guess that likelihood of a Senior Accountant being considered for an Accounting Manager role is greater for those with a CPA, so therefore the earning potential is greater for the Senior Accountant with CPA than the one without CPA, even if both their checks are the same size while they are Senior Accountants. Does that make sense?
How far you can go in the corporate world without a public accounting background varies, too. If you are wanting to be CFO or Controller of a large company that is audited by B4, then they may want to see B4 audit experience, but it's not 100% required most places and the further away you get from F500 type companies, the less you see it mandated. If you're looking for a Fortune 500-type career, then yes, B4 audit or large regional audit is going to be pretty helpful. However, if you are interested in working for the slightly smaller companies, then you can go far with less.
Last thought: Private to public is only hard if you want to be something other than entry-level in public. If you're willing to take a huge paycut and title cut, it's not usually too hard to move.