Andy Mass2,
Richard Graves has a custom in Canada using a 1-9 Krieger chambered in 7mm WSM that is getting 1/2 moa in 1000 yard BR comp with the 200 gr ULD RBBT.
I will be testing a Lilja 1-9 twist barrel here very soon with this bullet for my personal lightweight big game rifle to see if the button pulled barrel will stabilize it. I have one customer that tested them in a Lilja 1-9 four groove and got pretty good results out to 300 yards so it looks like it may well work.
My only concern is that Button pulled rifled barrels tend to be a bit slower in actual twist rate then advertised. It is only a small amount but it may make a difference compared to a cut rifled barrel which are generally pretty close to right on advertised twist rates.
I would say go with the 1-9 and try the 200 gr pills. If they work, great, if not, Richard also makes a fine 169.5 and 175 gr ULD RBBT and there are many others to use such as the 175 gr SMK and 180 Bergers so you will not be risking much and the 200 gr ULD RBBT may well work.
Good Shooting
Kirby Allen(50)