Need help with a .44 mag

Several possibilities. The same model rifle may not like the same ammo, no one can explain why this is other than the fact that no two barrels are identical. The scope could be defective, have you proved it out with a box test? The ammo - is it from the same lot as was fired from the other rifle? Even Hornady sometimes puts out a bad lot of ammo.

One more thing I can think of. I no longer zero a firearm with three shot groups. They prove practically nothing and can cause a fellow to chase zero all day long.

It was just mentioned on a different forum by a poster that he at one point had scope base mounting screws that were just a hair too long and were bottoming out in the screw hole but gave the impression that they were tight. Apparently the barrel gave him fits until he figured out what the problem was. Something to check if everything else is OK.

Try swapping scopes with a known good scope if you haven't already- there's a slight chance that it could be a bad scope.

Different guns like different ammo, though I can't imagine one would dislike a certain kind of ammo that it would produce groups that size. My Contender carbine 44 mag likes Winchester white box ammo just fine and I haven't tried any other commercial loads.

One more thing- the gun is brand new? Did you clean the barrel before shooting? Even if you did, either get some Remington 40x bore cleaner (and RemOil) or some JB Bore paste and follow the directions. If the gun is brand new or hardly fired, there could be a very, very slight burr in the rifling somewhere that is causing issues. Either the 40x or the JB will take care of that- essentially they will allow you to bypass a "break-in". I've used the 40x in the past, using between 50 and 100 strokes in the barrel and had good results.

Even if the gun is not new there's a chance the barrel is fouled with either copper or lead, run a patch soaked in cleaner down the barrel, run a dry one and take a look with a light shining down the bore. You'll see it in the grooves if it's fouled.

Last thing to check, and probably not something you'd think you'd need to check on a new gun: the crown. If the crown is bad or it got out of the factory without one, that would be enough to produce the results you are getting.

Good luck.

Could be four issues:

1. Your ammo might be a bad batch. Also ammo performance, in regards to accuracy, velocity, ect. vary from lot to lot.

2. Scope mounts might be too loose and change the POI with each shot due to recoil.

3. The mounting holes in the rifle might be out-of-line. Buy a one piece mount with windage adjustments.

4. The barrel's rifling might be defective.

Good Point. parson. Lot of these "lower priced" single shots are made in other countries, especially the barrels. While the possibility of having the wrong caliber marked on the barrel would be quite rare, it does show that the rifle wasn't checked-out before shipping. If this isn't his problem, being his H&R is not marked with the correct caliber; then I suspect the barrel isn't any good. I have a feeling a lot oof gun manufactures are using cheap inferior low grade Chinese steel thesedays in their barrel production.

Might be but where are they getting their material?

UM.................. Well I feel like the rear end of a donkey.
After reading all these posts I went and got the gun to look at the rings. Then I grabbed the scope and tried moving it. The whole rail is loose! Could this be the problem? It wasnt loose when I mounted the scope. Evidently the recoil loosened it up.
Back to shooting range.

On a .44 Magnum rifle; I'd go and buy a Leupold 2-7X33mm Heavy Duplex scope. One for shotgun/Muzzle Loader, as they are parallax free @ 75 yards. Buy this and a better mount/ring assembly.

Has anyone experienced any issues with the Marlin 44 mag 1894? i am picking mine up today and i have high hopes and expectations for this gun?

I had one that had a very oversized bore. I cast some .433 bullets that shot fairly well. That was a couple of years ago. Hopefully they have corrected that problem.