Have you wondered why you got a 50% rating and the other guy got 100% even though you seem to have more problems caused by PTSD? There is NO Answer to that question. You will not believe what some vets do for this rating. Many lie and do crazy things.
Here is how they rate you for PTSD. You have to prove you match their criteria according to 38 CFR 4.130 – Schedule of ratings–Mental disorders.
You have to understand VASRD (Veteran Affairs Schedule for Rating Disabilities). If you have multiple disability ratings, the VA uses them to calculate your combined VA disability rating. 38 CFR Book C, Schedule for Rating Disabilities
Did you prove your condition matches the rating?
CFR > Title 38 > Chapter I > Part 4 > Subpart B > Mental Disorders > § 4.130
Schedule of ratings – Mental disorders
The nomenclature employed in this portion of the rating schedule is based upon the American Psychiatric Association’s Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) (see § 4.125 for availability information). Rating agencies must be thoroughly familiar with this manual to properly implement the directives in § 4.125 through § 4.129 and to apply the general rating formula for mental disorders in § 4.130. The schedule for rating mental disorders is set forth as follows:
General Rating Formula for Mental Disorders tells you what percentage of the compensation you are entitled to.