I suggest a Ruger 77/44. The accuracy of one rem 788 with one Hornady bullet does not guarantee repeat performance with another example. These are old guns, typical well used, cleaned, etc. Back to the day prior to guys having 3 safes filled with queens.
Someone said the only data posted was for the 788, but there is a lot of 77/44 data out there for those who can use google. I did not see anyone talk about shooting any 44mag at 500 yards. That is less chartered territory. I read a Ruger would be doing well at 1.5moa, but; if someone put in the effort who knows? A serious person might do quite well with a 77/44. Very few purchase this gun for target shooting and most likely would stop load development or ammo experiments somewhere sub 2 moa.
If I saw a 788 in person, based on posts here, I would give it serious consideration. That is for myself, someday, just to try it. For the OP it could be a long wait or internet gamble. I think the OP is looking for a gun NOW. I think, accuracy is always a gamble with any rifle. Getting better than 2moa from any 44mag will require some combination of experimentation, determination and good fortune. Accuracy for even a 'good' 44 mag rifle can be all over the target with various loads and bullets. (based on google)
The Ruger has a faster twist, but I dont know how things trade off shooting heavier bullets at 500 yards in a 44mag with such limited capacity. Faster twist may well help stability at 500 yards even with medium wt bullets? Just a WAG. The Ruger magazine may limit ctg length and the 77 triggers need work. Might single load a 788?
I dont know if the OP is willing to hand load and make a major project for an informal club match. Then just getting a 77/44 and having at it makes even more sense.
The Ruger is available now, with a warranty. Ruger is now making the barrels so wild quality swings in the 77's, should be thing of the past. The triggers can be improved.
One review:
http://www.gunblast.com/Ruger-77-44.htm
The contenders had or have a great accuracy reputation. They made a carbine version in 44mag. While these are not rare, I think the contender maybe out of production since the S&W acquisition. But quality barrels are available and frames and stocks abound. These are an acquired taste. And they are extremely versatile. Might be the newer (bigger & better) encore is still produced and offers even more versatile platform.
Edit: I just re-read the Op's initial post. I must have got mixed up with first sentence and the last. Too much bs and typing, to just delete all the above. For a purely academic post, I expect a custom 77/44 could be built to win and any other suitable bolt, could do the same. Custom something. Single shot, heavy bullets seated out to lands, exotic stock, high end scope, very carefully assembled ammo.
