Ya most ammo will have a diff zero, for long range rabbits ur better of with light flat ammo like 40gr vmax, although my old rifle loved cheap 50gr hp american eagle and worked well on rabbits and corvids out past 300 when i did my part, heavier ammo is usually for target shooting so wont expand enough to be used humanly for hunting although it can work on bigger animal, but on rabbits it will prob just zip through them like fmj's

your not going to shooting much from the Hornady range under 55gr due to the 1 in 8 twist.

You'll spin 40gr @ 340,000 rpm, 53gr superperformance @ 311,000 and even the 55gr Vmax @ 291,000
Hornady have a suggested Max rpm of 290,000! before the bullet rips itself apart.

Fedral premium using sierra bullets have a 340,000 max rpm
try to get some 55gr nostler balistic tips - 291,000
69gr sako are also a great round for that twist.

If its a 1 in 9 twist the 55gr vmax will be perfect @ 259,000 rpm and easy to get

johnfaul wrote: »

Im shooting norma 50 grain v max through a 1-8 its giving well below 1/2 inch. Shot a pigeon over 250 yards yesterday and blew him apart.
Ive also read on the english forums that some are shooting 40 grain with very good accuracy through 1-8 twists, try a few different brands and find what the rifle likes, you may be surprised good luck

Ballistic coeficient matters. We typically go by weight because heavier bullets are normally longer, but not always. Generally the faster twist is for longer bullets relatively speaking (& longer are usually heavier).

1:8 is somewhat of a compromise twist rate and should be able to give you good performance for a decent range of bullets. A quote from an internet post that I refer to from time to time that is illustrative and I think backs what johnfaul is saying:

"a recent Handloader magazine test found that 40-gr plastic-tipped bullets (these are a bit longer BTW) shot the best of all lighter loads tested in a 1-8" Rock River Varmint AR15 and a 1-9" Savage bolt, with the accuracy edge going to the RR AR15. These were 1/2 MOA groups. However we need to remember that it was a smooth match-grade barrel with a long concentric high quality 40 grain bullet. Shorter 40 and 45 grain SP bullets intended for the Hornet shot very poorly but were plenty stable!"

My T3 lite stainless 1/8 is quite fussy.
Best result was with 55gr Fiocchi sp.
second best was Sako 55gr sp.
edi

Mike87 wrote: »

Please let me assure you, any rabbit I ever shot with the 64/75 grain was left looking like he was sitting on a grenade. I have never once had to a put a second bullet into a rabbit while using 64/75 grains.

Well i've had 75gr bthp zip through, i had a 1:8 sako and it shot 50-80gr well, only thing it wouldn't shoot was 55 gr federal sp but loved hornady and fiocchi sp