Great looking bow! I have a very similar Robertson Vision longbow, 61#, 64". It looks like your longbow grip sleeve is set up to facilitate takedown. Most of them require a certain amount of fiddling before you can take the bow down, which is fine if you rarely need to take it down. Interesting, I have two Robertson takedown longbows, and have seen others, and every one I've seen has a different grip sleeve.
I shoot a Gold Tip 5575 arrow in mine, cut to 29", with a 20 grain brass weight in front and another 20 grain brass weight in back. I use 145 grain points or 150 grain broadheads.