I'm a firm believer that the single most useful caliber that exists is the .22lr. If I had to go down to just one gun to do everything with, it would have to be a .22. The only thing that the .22 is the best caliber for, is hunting small game like squirrels and rabbits. In a survival situation though it will kill anything with good shot placement. I'd rather try and kill a deer with a head shot from a .22, than trying to fill the pot with small game shot with a 30-06. If you factor in cost and availability, you can buy two bulk packs of 550 rounds for the same price as one box of most centerfire calibers. My favorite .22 that I own right now is a Ruger 10/22 and if I was forced to go down to just one gun, this would be it. The one problem that I do have with the 10/22 is how finicky it is to different brands of ammo. The gun will shoot Remington golden bullet ammo 100% of the time, but with Federal red box bulk pack it will jam once every 15 or 20 rounds. Someday I'd really like to get a Marlin 39A which should combine reliability with high capacity. With the jamming issues though, I don't think that the 10/22 fits the original question about most reliable.

Now that I've rambled on about the most reliable caliber when the original question was about the most reliable gun, I'll try and answer the question. It's hard to pick one overall since they all were bought with different intentions in mind, but I'll list my "go-to" guns for each purpose. Never once have any of these guns failed me.

Home defense - S&W model 19 .357 Magnum
Concealed Carry - Ruger LCP .380 acp
Deer Rifle - Marlin 336SS 30-30
Big Game Rifle - Remington 700BDL 30-06
Slug Gun - Marlin model 55 12 guage
Turkey Gun - Remington 870 12 guage
Bird Gun - Mossberg 500 20 gauge

Ruger Gp-100

From the cheapest, dirtiest .38 handloads through 180 grain .357's without a mis-fire. Its my house gun and hog gun.

my most reliable gun would be my good ol enfield .303 since its 96 years old and still prints under a 7/8 group while its wearing a scope.

I'd agree. Unmodified (matching serial numbers) Enfield No. 4, Mk 2...original iron sights. I don't think you could kill that rifle without welding a plug in the barrel.

One ALL PURPOSE gun

My 870 Remington Magnum Express..

turkey choke reaches out there and has gotten me turkeys
Improved cylinder puts slugs consistently in the 2 1/2 " circle at 100 yds.
What more could I ask for..I'm sure it can drop squirrels too
:s1:

I guess nobody has ever used a Win. Model 12 pump gun. Mine was manufactured in 1934, and has killed more pheasants, grouse, ducks, geese, rabitts ans squirells than you can count. It was my dads and now is mine. Never had a jam or misfire in that gun.

Savage .270 with Acu Trigger. Nothing short of a tack driver. Shoots a 1 inch or less group at 100 yds with factory ammo. As a matter of fact, thats it in my avatar.

Mossberg 835

It would be hard for me to pick one but these are a few stand outs. My Savage 110 7mm mag for deer hunting. Due to over 25 years of hunting (many of which were in
-30 temps or colder). Never a doubt when the cross hairs were on an animal and the trigger pulled. My 870 for all the days in the rain and mud of the goose pit. My Cooey .22 lr which was passed down from my grandfather and am sure is close to 100 years old. I must admit that posts on the .303 Lee Enfield hit the mark also. It was my first deer rifle(which I still own) and I'm sure it would still punch tacks at 50 to 100 yds. with iron sights if my eyes were still young. Kind of sucks to realize that you are wearing out before your equipment

We are getting carried away. I trust all my guns also, but if I have to pick one, it is my Marlin 336 30-30. Never has let me down.

I love my Marlin 336 as well.. I thought the question meant one gun for every huint..rabbits, pheasnts , wild hogs , deer etc..then that would be my 870 shotgun..

I mostly hunt in a thick swamp...for hogs and deer in Florida..my 336 Marlin is tops..

BUT ALL AROUND PUTTING MEAT ON THE TABLE..870 is my #1 choice