Round Bullets in Whitworth-polygonal bore

[TheDoubleD]

I am getting ready to load ammo for my Westley Richard 1871 Express rifle in 500 No.2 Express. The bore is Whitworth rifled. If I can make this gun shoot I hope to use it on my bear hunt to Manitoba this September.

I am concerned about the shooting round bullets in the polygonal Whitworth bore. I am asking for your opinions on this.

The bullets I have available are as follows.

1. CBE .510 440 mould. This seems the safest option shooting malleable round bullets in a polygonal bore.

2. Woodleigh .510 440 grain RN SN. These bullets have a thinner jacket designed for Black powder express rifles. I would think they should be fine in a Whitworth bore. I have 55 of these bullets.

3. Barnes Original .510 450 grain. An unknown to me.


Would like to hear your opinions on these bullets suitability in a polygonal bore.

FWIW, i will be cross posting this question else where to get additional opinions.

 

[TheDoubleD]

Here is my bore. 8 groove.

 

[Grumpy gumpy]

I would use cast as that’s what it was designed for, and I like cast. You may get blowby with jacketed or damage the throat, it’s a 150 year old gun, treat it gently
Gumpy