Ron K has several choices for his Frontier.
All of these will be in the Standard Pressure. I certainly refuse to try and make my Colt SAA into something that it is NOT.
Garrett makes his 260 or 265 gr stuff for 2nd and third Gen Colt. around 1000fps.
Barnes makes some good ammo with a 200gr XPB they rate 1025fps
Remington uses the same bullet and it is a little slower and about $4.00 less per box.
Buffalo Bore uses same bullet and velocity is similar.
For Deer or Hogs that Barnes works.
Winchester makes a Bonded Bullet in their Defender ammo, (again this is loaded ammo to Standard Pressures).
For those who remember it looks like the Black talon bullet only in a copper version. Unfortunately, this ammo shot 4" high in my SAA. I would someday like to try it in my Trapper.
Rimrock and GT bullets are 2 bullets that I have not got to try yet, but I think (In a cast) they would hopefully work, at the slower velocities needed for the COLTs.
I did try the Hawk Bullet last year on a Deer and it did the job. I did not like that soft of a bullet out of my SAA.
Recently I used the same load and Bullet (260gr) out of my Rossi Trapper (16" barrel) and it proved that a soft bullet can work well with correct bullet placement.
Bullets and loads have to be tested in each individual gun for accuracy, then if it does not have a proven track record, I would like to see or hear of a Range report.
200gr - 265gr should work fine with 900 to 1000fps
I do not always roll my own,,, When I can get Federal or Barnes loaded ammo, I grab them. My time is very valuable. I see no need to reinvent the wheel.