I build for myself mostly. I am tall and like a 15" pull when possible. My first full rifle build was a .36 long rifle. I made all the mistakes you could possibly make on it but it still turned out to be a good rifle. It was my only flinter for a few years and brought home plenty or rabbits and plunder from many shoots. It is the top one in the picture.
The second one is a little .32 I built about four years ago. I wanted a light weight rifle to chase bunnies with and shoot squirrel gun competition. It has a 3/4" x 36" GM barrel and is just like shooting a .22.
The bottom one is a .58 flinter I built just before the .32. I bought the barrel and lock about 20 years ago but changed careers about that time. I hauled the parts around for about 15 years and finally got around to building it when I retired. It is a full stock flint Hawken. It does great in big bore competition.
My first percussion was a CVA Mountain Rifle I built from a kit in the seventies. It was a good shooting rifle but didn't fit me very well. With 100 yard and hunting loads, it would smack me in the cheek. I restocked it with a Leman stock to give me enough drop and enough pull to shoot comfortably.
This rifle was built from parts I had packed around also. It was the first rifle I built after I retired. I was definitely rusty in my skills. I named the rifle Murphy because everything that could go wrong went wrong when I built it. The rifle came out nice though and it is a great shooter. It has a .50 42" barrel tapered from 15/16" to 13/16".
There are others I have built that were destroyed in a fire. The one I have that I don't have a picture of is a .50 Tennessee. It has a 42" 7/8" barrel with an L&R Manton lock. This particular rifle is a tack driver. Works way better than the operator.