I have never worked with any one table that has that many fields, though I have HAVE seen some in the major Airline Cargo industry that have that many - or more. That was in the mainframe world and was a whole different ball-game.
Since you haven't provided much information about your Table itself - or the data, here is a suggestion that you might be able to use.
On each Form, instead of 'Inserting' a record as your Forms are doing, create a button that 'Updates' the record you are working on.
In order to Update, you have to be able to identify the record [in your Table] that needs to be updated with the info on the current Form.
Here's a quick one-field example of what I'm talkng about.
In this example:
I update a Date field in a Table - YourTableName.DateField . . .
With a Date from a text box on my Form - Me.DateFieldOnYourForm . . .
Using an ID value from the Form that matches an ID value in the Table - WHERE YourTableName.PrimaryKeyField = " & Me.IDFieldOnYourForm.
Code:
'Update a Table with values from a field on a Form.
Dim db As Database
Set db = CurrentDb
db.Execute ("UPDATE YourTableName SET YourTableName.DateField = #" & Me.DateFieldOnYourForm & "# WHERE YourTableName.PrimaryKeyField = " & Me.IDFieldOnYourForm)
Hope this helps. Let us knopw if you have questions.