Davy, to be honest mate, you have never gave a combo a decent run! the rifles you have had, no doubt have been as accurate as each other. many have had adjustable stocks and good triggers.
You can jump about from one gun to the next, one scope to another, and never see improvement. stick with a gun and get your technique nailed with it.
I have mulled over upgrading this year, but have decided against it. determined to whip some *** with my s400 this year. the rifle is more than capable. Wind estimation and lack of practice was my downfall last year. Gonnae try and rectify that this year. A new expensive rifle wouldn't have made an iota of a difference on my scores, because bar the odd flyer, my misses were my fault. Bottom line, theres a saying regarding workmen and tools