That is why I included the make and model of rifle.
Doesn't matter what make and model of rifle. Each rifle is unique. If you're retired, curious, and have money and time to burn, buy ten rifles of that make and model; then start testing each load combination in each rifle. There will be a variation in grouping results, whether big or small. (I did something like this once: buying 10 rifle lots of Long Branch No.4 Mk1, cleaning them up and then shooting them for group, looking for the one of all the examples that grouped the best with Mk VII ball ammo)
The only relevance is whether that make/model of rifle has developed a reputation for better than average grouping ability or not.
I have a Sako 30/06 Forester I bought somewhere around 1974; first new in the box rifle I ever bought. It groups very well with most, but not all, hunting bullets I have trialed in it. I'm sure your rifle model (that I have no familiarity with) will group very well with most of the premium hunting bullets that are available off the shelf. Meaning your rifle MIGHT group a little bit better if you spend a bunch of money having your reloader friend put together loads using different powders and different weights of those powders with the exact same (or similar) premium hunting bullets.
These days, as far as moose hunting accuracy goes, I suspect it is hard to buy a hunting rifle that doesn't group extremely well. Look at all the entry level plain jane 30/06 rifles being offered by some manufacturers who guarantee 1" accuracy with factory ammunition. That is definitely Minute Of Moose. Would still be Minute of Moose if they "only" managed 1.5 MOA. Differences in velocity between factory and reloads with the same bullet will be meaningless in the real hunting world.
I have happily spent a lot of money and time over the years developing the best load possible with premium hunting bullets for each of my rifles. But I enjoy (less as the decades go by) reloading and developing loads in my hunting rifles. That is a hobby all by itself, apart from hunting. With my standard caliber rifles, I could probably go buy a box of factory ammunition of the bullet model and weight of my choice, and I would lose little to nothing hunting with factory ammunition in the real world versus by hand assembled and tested reloads.
If you're willing to invest the money for the components and your friend has the time to assemble a range of loads for ladder testing, AND you're well enough practiced off the bench to do that testing at 200 - 300 yards so that the different grouping ability is due to the loads, not variations in your shooting off the bench, then go for it. Shoot some exemplar groups with factory premium hunting ammunition to get a baseline for comparison to see if handloads are giving you any benefit.
Otherwise, I'd suggest you use your friends offer to reload for you by having him reload a whole bunch of practice ammunition for you to use practicing and improving your field shooting skills. I would bet a small chunk of change that not even 5% of big game hunters fire even 10 rounds from a variety of field shooting positions each year. They shoot off the bench at 100 yards, maybe a couple offhand while they're standing beside the bench, then they go hunting.
Whatever the actual percentage of hunters who do some meaningful practice is, as far as best return on money spent by you and time by your friend to reload, you're probably far more ahead if he's reloading practice ammo while you're buying premium hunting ammunition off the shelf.