As I said in that story referred to in my last post;
I hunt a lot with open-sighted double rifles, and have complete faith in the skill and ability of last century's British gun-makers to properly regulate their arms. If a sight-leaf is marked with a particular distance, you can be sure it was test-fired at that distance and the sights carefully filed-in to place the bullet on the mark. This is more than can be said for the open sights on most modern sporting arms, the vast majority of which will be scoped before leaving the retailer's premises.

The early hunting literature is rich with tales of satisfying shots made with open-sighted doubles and stalking rifles, both in the highlands and the far-flung out-posts of Empire, and they are no less accurate today than during the hey-day of British gun-making a century ago. For some reason, the shallow-vee express sights, and British doubles generally, are often accused of mediocre accuracy at best, when nothing could be further from the truth. Admittedly some specimens have suffered greatly from the ravages of time and ignorance, but the majority of surviving examples have been well cared-for and are capable of delivering 'every satisfaction' as far as hunting accuracy is concerned.

In practice, I rarely deploy the flip-up sight-leaves on sporting rifles, as they are so infrequently required in the hunting field. Nevertheless, it is reassuring to know that when a long shot is called for, these marvelous rifles from a bygone era are still capable of holding their own in any company!