As RM stated above, most of these were bespoke guns so it was whatever the customer desired. With that said, most, if not all magazine rifles I've seen of that period had horn forend caps if they had one at all. Its not uncommon to see a Holland of that period with no forend cap. H&H rifles, both magazine and double, seem to predominately have 25 inch barrels. There are exceptions but that appears to have been the Holland standard. HTH!