I recently purchased one of the dubious quality Sabatti Double Rifles in 9.3x74r. I looked over the rifle closely and it does not appear to have the issues of the crown and bore that some of them did.

The regulation target shows the right barrel 2" diagonal up and right of the left barrel at 50 yards point of impact. I believe it was regulated initially with Hornady 286gr SP ammo.

Questions:

Will following any sort of break in and cleaning regimen result in further accuracy on such a gun?

If I don't wish to handload, should I buy 4-5 different types of 285gr/286gr ammunition to see if any ammo provides better results or am I still likely to have similar performance with factory ammunition in a DR?

The dealer that sold it to me gave me a 100% return or exchange policy on this if the trajectory's cross or if it doesn't shoot well. In short, at what point should I say "I don't like it, give me another one" and rinse/repeat the process?

Thanks!