I looked it up–the only Arisaka ammo I can find is expensive or backordered. Too bad–supposed to be an excellent shooting rifle.
Many thanks kind one for your thoughtful post. I have a bit of a local expert that I can go to with my questions but for complicated reason, I don’t want to go to that well any more than I need to. (OK, not complicated, he’s a cranky prick who knows exactly what wrong with everybody else.) He explained the differences between Garand approved and most modern loads and gave me the same choice you did.
He then offered a two syllable expression of contempt for the idea of even temporarily modifying the rifle. His suggestion is that I should start custom hand-loading (or even better, buying his hand loads). Better quality control and a more reliable supply at lower cost he says. I’ve done some hand loading and have a solid single stage press, powder scale and most of the other misc gear I would need. I still need to source the components which isn’t all that easy either and I’m not sure I want to make that kind of investment in time.*
In the short term at least, I don’t need to worry about ammo. I have probably two dozen clips already loaded with my father’s hand loaded shells so that should get me well through the experimental stage. I have no clue what the bullet weight or powder charge may be but Dad loaded them specifically for the his Garand so that’s good enough for me. After that, we’ll see.
*Another good reason to start hand loading is than in my first post, I said that Dad named two specific weapons that he had reserved for me. The Garand was one. The other was a Colt 1911 (70 series) chambered in Super .38, and I have not had a lot of luck finding commercial ammo for it. I like shooting that Colt and if I want to do it very much, I better get to loading.
Keep it for the cool factor. You’ll never find another Dad’s M1.
My dad had one. When he died, my asshole brother stole all his guns before his body was cold. I was only able to recover an M1 Carbine from his wife when he kicked it. I’d love to have the Garand as well, but damned happy to have the Carbine.
So what if it sits in the safe unused? 99% sure that is exactly what it will do if you sell it. Keep it. Or sell it to me!
This and this! We shoot Dad’s once a year, and its an event. We invite people who have drooled over it, everyone gets a turn shooting it and a good time is had by all. (Then we go back to our place, eat BBQ, drink beer and tell lies.)
I’m really sorry your asshole brother stole your dad’s guns, @Gatopescado. Death and greed make people even bigger assholes than they usually are. When Dad died, one of my sisters got upset because Mom didn’t sell their home and split the money with everyone right away.
Hopefully your father’s Gerand has a nice comfy spot in someone’s gun safe somewhere!
Back to the OP -
When you say “it was Dad’s rifle” do you mean it was something he carried in combat? Or that it was especially treasured by him? Or just that it was one of “70+” weapons he’d accumulated during his life?
ISTM there’s nothing particularly great about them as firearms by 2020 standards. All the interest is in the nostalgia, whether for family-specific reasons, or WWII was soooo cool! reasons.
If you treasure it, keep it. If it’s just another one of your firearms, it has no special place in your vault. OTOH, if you have a large collection and this isn’t a specifically collectible edition some hard-core Garand collector would value at a silly high price, what’s keeping one more in your racks going to hurt?
It was NOT combat carried by my dad. To the best of my knowledge, it was not connected to his time in the National Guard in any way. As far as how he may or may not have treasured it, he specifically chose that weapon for me in his will with full knowledge that I had never fired it. Make of that what you will.
I have no reason to believe there is anything especially collectible about this weapon. The receiver serial number of 99**** indicates production date of Nov '42 but that’s nearly meaningless as these weapons have been taken apart and refurbished by so many different entities that a complete, numbers mating Garand is almost unicorn rare.
Fair enough, but the reason I made the point is that the vast majority of Garands I’ve come across and fired are, shall we say, less well maintained. They are on their third or fourth owner and often had quite a few rounds through the barrel. And often with inappropriate ammo as has been discussed. But yes, it was a fair cop to call me out for automatically blaming that on the action rather than the gun’s condition. 
I did want to make an addition point to the OP @Alpha_Twit as well as accept my come-uppance: one of your points in keeping it was it is your only high powered/long ranged rifle. If you are keeping it on that basis (which isn’t wrong by any means), what is your intent for it? Are you looking at hunting heavier game? Is it for TEOTWAWKI? Is it a ‘just in case’ you get invited to go hunting with a friend for heavier game? This is going to make a difference in terms of it’s value to you above and beyond the monetary and emotional value.
PS - My favorite lever action is a PCC as well, a Rossi in .357 (and yes, I had to give the action some love) but dear god it’s fun to shoot and my father-in-law is always reloading .38 and .357 (when he can get supplies).
This thread made me look up to confirm what I believed: My Garand (H&R) was built the same year I was born.
I don’t know that I have any firm plans for it. It just seems wrong to m that it’s sitting in my gun safe and I don’t have the knowledge to use or maintain it. Much like silenus, if I can take it out, go to the range and do a little target shooting every year or two then that’s fine. That basic degree of competence gives me options if some more interesting opportunity or pressing need develops.
Heh. Yeah, let’s just say that mine probably has a “lot of history”. Mine definitely wasn’t sitting on a shelf being well-maintained since it was built in 1944.
Here’s mine (along with my Mosin-Nagant, K98, and Type 99 Ariska)
And now we know who to visit for the zombie apocalypse! 
Very nice BTW, very nice. What do you use to protect your furniture (in both senses of the word)?