Slow down, most true collectors would not go with this attribution, I have already stated that this box was likely captured, it could have been at 2nd Manassas or Winchester and the original owner's initials are inside the flap. I have well over 100 federal cartridge boxes, the majority have initials or names on the interior, while my CS boxes and accouterments all have names or initials on the exterior. Small sample size, but a good rule of thumb, plus it appears as if the initials were crossed out.
There were times a soldier would also hang onto an accouterment when a reissue occurred, he may have thought he could cram more rounds into the box or why change anything if my luck has held out this long. The box is obviously Federal and the cartridge box plate was on it for a long time as evidenced by the impression, which favors Federal ownership. The Federal soldier may have enlisted under his first and last name (no middle initial) but decided to add the middle initial since there were others in his company with the same initials
As has been stated earlier, if you are happy, that is what counts, but the attribution is extremely loose and not one that would be accepted in serious circles.
Surely you meant regiments and not battalions:
"There were under 20 battalions with .69 issued ammo at Gettysburg in the union army I think perhaps you could shed some research"
The important thing to remember is that no one knows when those initials were carved into that box 1861-1863.