I have not read all the replies, so apologies if what I am typing has been spelled out by others. But! Here is why I love Ruger no.1's.
1) There is a certain appeal to a single shot. I think it relates to the idea of the commitment to accuracy, to use single shots in the field is to say: "I intend to take exactly one perfect shot, and to have that shot settle the matter". This ideal appeals to me, single shots are a perfectionists rifle.
2) The length is a huge advantage. To use a single shot is not just to give up extra round in the magazine, there is a trade off, which allows you to save around 4" as other have pointed out. So if you want a handy gun to hop out of a vehicle with, or to backpack with, any No1 with a 22" barrel is the ticket.
3) The Strength! There are lots of single shots that take advantage of the first two points. BUT, unless they are also a falling block based single shot (like the M10) they will not nearly be as strong. And the strength of a Ruger No.1 is no joke. I have two in DG calibers, a 500NE and a 450/400. And those two can be safely loaded up such that the 450/400 hits the 404 jeff levels of energy. And the 500NE hits 505 gibbs levels of energy... However... Your shoulder may disagree with this practice.
4) Ease of making stocks, if you are a handy wood working guy, it is relatively easy to make a ruger no.1 stock. You just need a router table, and an angle grinder with a flap disk. With those two things it takes about a weekend to make both pieces of a stock, and have them sanded to the point they are ready for oil.
5) Accuracy. Yup... I said accuracy. Many bemoan the accuracy of the ruger No.1 but I have yet to own one that does not shoot. I do float the foregrips on mine, but that is standard accurizing for bolt action rifles as well. Once this has been done, every No.1 I have had shoots around or just under 1" when I do my part. The one exception is the 500NE, that shoots around 1/2", but that has a match grade stainless 50bmg barrel that was cut down and re chambered to 500ne. Alas the only way to get that accuracy is to shoot it off a bench, and that is horrendous.
6) Cals. A Ruger is a bit of a pain to change barrels on, as you need to change your extractor, and get the blank end milled for the extractor slot. BUT... It allows you to change a ruger to any cal you want. The same action can be a 7x57 OR a 500NE with a barrel swap.
Here is my favorite, the 500NE... We were tracking a buff when we came upon this sable, it was late in the morning so we figured why not, and it took a 600gr cup point solid through the chest. Stock made by yours truly.
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