What do you guys think? What would be the best twist considering that I want to be able to shoot long/heavy bullets, but also want to be able to use lighter bullets for PG and such.

Are there any deleterious effects from going to a faster twist?

Any comments appreciated.

I have tested three .416 Rigby rifles and one .416 Taylor rifle, all with 14" twist barrels, the customary twist for a .416. All have been fine with 350 grain to 400 grain monometals, and all the lead and tungsten core bullets I have tried. I have not tried 450 grainers but I think the lead cored .416/450gr bullets are shorter than the 400gr monometals, and length of the bullet is what matters.

The last .416 I had built was a .416 Dakota on a Winchester M70 using a Douglas stainless barrel of No.4 sporter contour with 12" twist. Ditto on the bullet testing.

You can't go wrong with either of those twists.

I also have three rifles of .423 caliber that all have 10" twist and they are fantastic.
It makes sense that a 10" twist in a .416 would also be fantastic.

Whatever turns your crank: 10", 12", or 14" twist.

At hunting ranges (well under 1000 yards), "too much twist" just won't happen, but better penetration with the long and tough bullets might, with the faster twists.

But my 14" twist with the .416/380gr GSC FN @ 2500fps sails right through cape buffalo shoulder to shoulder and out the other side, as well as two large umbrella thorn tree trunks when you line them up.

14" is fine.

What would be the downside from going with a twist as fast as 10"? Why is the standard twist 14" when having a faster twist has some advantages?

Anyone out there with a 1:10 twist on a 416?

bulldog,

I believe the standard twist used by the Brits for the .416 Rigby was
a 1 in 16 with 410 gr bullets at around 2350 fps...

I am having a .416 Rigby barrel made up and 1 in 16 is the twist rate
I went with.

Not sure what you would/gain loose with this combo using 450 gr bullets....

Regards,
Dave

I think David is right, the standard twist was between 1:16 and 1:17. I am having a 416 Taylor built for my stepfather with a 1:16. I would think that the 1:14 would be fine, and RIP always does thorough testing so I'd think you could safely depend on his findings.

Red