I have preached the value of .380 inch balls in .36 revolvers for about two years now.
I still believe it.
I have a Colt 2nd generation (circa 1981) 1851 Navy whose chambers are so large that a .375 inch ball is nearly a slip-fit. It is mandatory that I use a larger ball in this revolver.
In the past, before I purchased a Lyman mould that cast .380 inch balls, I used .375 inch balls. The rammer also would often pull the ball back out after ramming it down.
I discovered that it's not the rammer, per se. It's the lubricant on the face of the rammer that apparently creates enough of a suction to yank the bullet out.
The lubricant on the face of the rammer generally gets there two ways:
1. Lubricant is used over the ball. During firing, the rammer unlatches and the rammer drops against the grease over a ball.
2. When greased, felt wads are rammed down on the powder, before the ball is loaded.
I have been using .380-inch sprueless balls from Warren Muzzleloading of Arkansas for nearly a year now. An excellent product! I ordered 1,000 of them (10 boxes) for less than $70, which included shipping.
These oversized balls also give better accuracy in my Uberti-made 1858 Remington Navy and my Armi San Marcos-made 1862 Colt Pocket Pistol.
I don't often use .375 inch balls now.
The larger ball does, indeed, create a wider bearing surface for the rifling to grip.
As for accuracy of the elongated ball, I have no complaints.
Last summer, I was given a few dozen swaged .433 inch balls. As an experiment, I tried them in my Colt 1851 Navy, from a benchrest, at 25 yards.
Boy, talk about leaving a ring of lead after ramming that ball .059 oversized!
Interestingly, accuracy was on a par with the .380 balls. I only fired a dozen of the .433 inch balls so it's not much of an experiment. I stopped the experiment when my hand grew weary from seating those vastly oversized balls.
In retrospect, it was probably a dumb stunt. I risked bending the rammer pivot screw by having to apply so much force. I don't suggest others try this experiment, especially with one of the poorly made revolvers so often seen on the market.
But the fact remains, the .433 inch ball was swaged into an oblong shape but accuracy apparently did not suffer.
I continue to recommend .380 inch balls for all .36-caliber revolvers. They are easier to find, thanks to Warren Muzzleloading. I've written both Speer and Hornady, suggesting they offer this diameter in their swaged lead balls, but aside from receiving a polite reply I've received no indication of interest.
It's a pity, because I think it would be a popular and useful ball size. As I pointed out to Speer and Hornady, it could also be used for very light gallery or small game loads in the .38-55, .378 Weatherby or .375 Winchester.