First of all, rights should be restricted for felons on a case by case basis, preferably by the judge at sentencing. All those rights should be returned when the felon finishes their "sentence"
Sentencing needs to change a bit, too. I'd expect sentencing should go something like this:
"John Doe, you are sentenced to 25 years for X." Your 2nd amendment rights are suspended for the duration of 25 years no matter your status in prison or parole or on early release.
The problem is that would over time be abused to give everyone charged with most offenses lengthy prohibited status. Relatively petty crimes people are only expected to serve a very short sentence over would have the technical sentences significantly lengthened to allow for long term denial of rights, long after they are expected released.
Rights far in excess of just firearms, including search and siezure, etc
In fact there was just a post about probation I commented on.
Probation in CA can and usualy will have a condition that includes no weapons even for minor offense, as it is the policy of many probation departments to include that provision standard.
That can include even very minor offenses only punishable by less than a month in jail as a maximum sentence. Any criminal probation whatsoever, no matter the crime.
Disturbing the peace for example, which can be for loud music, using profanity etc could result in probation lasting years that has as a condition that no weapons will be possessed.
Does that not undermine the purpose of the Bill of Rights and the 2nd in particular?
Such people found in possession of a firearm are the same as a felon under CA law.
So essentialy any minor offense in the state can be a lengthy prohibition of arms lasting years, and anyone that violates that can be charged with a felony.
Your proposal of denial of rights continuing upon release would have the same effect on what sentences were given over time. Crimes people felt deserved an actual year of confinement time would in fact have a few years given to allow for a lengthy denial of rights period.
Crimes commited people felt deserved 5 years would result in 10-20 year sentences to allow for a lengthy denial of rights period.
Etc
The sentences would over time adjust to compensate for the denial of rights period.
Parole and probation really should not exist. People should recieve reasonable sentences for a crime, and be expected to serve the time. That way realistic sentences are given and things are not clouded.
Sentences are not longer than reasonable because the individual is expected not to serve most, and where rights begin and end is not clouded.
Sure that might make motivating good behavior in jails and prisons more difficult, but it seems better than clouding the rights of society in general for that minor benefit.