Has anyone considered converting a H&R or Remington Sparten rifle to 9.3x74R, 400 NE, or one of the 450 NE cartriges? The actions would seem to be strong enough. They are both produced chambered for 270 Win. I would expect it to be the lowest cost conversion of that type. Most of the work would be in fitting the extractor. What do you think? Are they too crude of a gun to be worth while?