You may be making a huge leap and assumption when you are blaming the factory loads for inaccuracy in a 760. There are too many 'youth size' rifles and carbines out there that happily digest all manner of factory loads. Over the years, I don't know how many articles have been written, showing that short barrels and relatively slow powders are NOT a problem. Check your bore after firing, I'd be awful surprised if you found any unburned powder in the bore. The 760 by it's design, is a difficult rifle to shoot off a bench, untuned triggers are terrible, wobbly forend, barrel is a slip fit in the action, 2 piece stock, there are 3 or 4 different bbls in the history of the 760...Remington trying to get it right, please don't be offended, they are a fine hunting tool...but don't expect too much.
No insult intended of your experience. When you shoot the 760 off a bench, grip the rifle, fore and aft in your hands firmly, the front hand resting on the front bag, do not let the barrel touch the bag...don't let the forened rest on the bag, it will be in your hand which will rest on the bag. Try to pull the long gritty trigger straight to the rear directly in line with the thumb web. With the sloppy forend it is very easy to bias the rifle in the horizontal plane by a careless trigger pull. There is more , but I've already pissed you off i'm sure.
