I should add that I originally meant for hunting when I started the topic.
It was a very clear question but now you muddy the water because it all depends on what type of hunting!
And what's in that .007 inch that makes folks reach for the .257 and not the .25? Available barrels mainly?
Yes barrel and ammo. Normal airgun .25 barrels with 1:23 twist rate are considered fast and .25 slug barrel are around 1:18 shooting shorter and lighter 40 grain and lower slugs. the .257 barrels are designed for heavy slugs only with twist rate of 1:14 range shooting slugs 90-200+ grains with BC of .22 vs .09 of normal .25 slugs and .33 of .25 pellets. Completely different system/design. The .257 boat tail slugs have the highest BC of just about any slugs which means it has the best down range accuracy because it will be slowed down the least or fly fastest down range which means less drop and less affected by the wind.
I’ll try to clarify it even more, let’s say there is a praire dog out in the open at 200 yards, you can pick any gun, any slug. I’m surprised I haven’t heard more people bring up the impact which I thought would be most peoples answer, also surpised I haven’t heard any daystate or RAW answers. I ask this question because I planned on waiting until this spring to buy an impact mk2 or see if a mk3 was announced, not knowing a ton about tuning though I am kind of worried about getting an impact as it seems to be a gun made for people who are extremely into tuning. Not saying tuning is something I don’t want to get into, it’s just something I don’t have much knowledge on as of now and would be worried about my ability to tune a gun like the impact, I feel I would find myself getting frustrated a lot. Because of this, i’ve started looking at other options such as the RAW. I plan on hunting with slugs and reaching out to ranges of 150 and maybe potentially further. My taipan did great out to 100 with pellets but didn’t like slugs so I decided to try something new.