Maven
07-29-2014, 04:37 PM
johnson1942 & I were discussing inlines and how to maximize accuracy the other day (via PM's). He mentioned heavy (at least 500grs.), paper patched conicals and unpatched RB's seated over some kind of cushion/wad. Not having so heavy a conical on hand, I decided to experiment with an unpatched ball, which I did have on hand, albeit in a much larger diameter than my .50cal. Knight Bighorn could use. After some deliberation, I wondered whether I could size a .530" ball small enough for this test. Well, I happened to have a .518" sizing die in my RCBS Lub-A-Matic I which I use for lubing Maxi-Balls, that looked like it would work. It did, sizing the balls nicely and shaving a thin ring of Pb from most of them. I next removed the breech plug from the rifle, oiled the bore, and drove the ball through it (muzzle -> breech). It mic'ed .512" x .504" and shaved another Pb ring in the process.
Today's range test results: Actually, I wanted to test .490" (.492") RB's with 2 different patch thicknesses, .018" & .021" before I tried the bare balls. Using 55grs. Diamondback FFg and patches wetted with 1 Ballistol : 6 H2O, I got a1 3/4" x 1" 6 shot group with one patch and a 1 1/8 x 5/8" group with the other @ 50 yds. If I ignored the high shot from the 1st group, it would have measured 1" x 1/4". Bore fouling and subsequent reloading was fast and easy, but I did notice that the bbl. needed as many as 5 fouling shots to settle it.
The bare balls were another story and only a partially successful one at that. The nominally .518" RB's, which originally were .530" were dipped in a hot beeswax - Crisco mixture, as were the 1/4" felt wads I used under them. For this test, I used 60grs. FFg also @ 50 yds. I also wiped the bore between shots with damp patches from the first test (above). My efforts, however, were not exactly rewarded with a small group: a 6" pattern would be a charitable description, although 2 shot (out of 5) did touch. Next, I trimmed the petals off 6 MMP High Pressure (HP) sabots, saving only the base section for use as an over powder wad. I seated them with the concave base toward the powder charge. The naked .518" balls were then seated atop the improvised OP wad. I damp swabbed the bore after firing each of these as well. The result was quite good, especially when compared to the bare ball, felt wad combination. 5 shots went into a 3/4" x 2" group. What about the 6th shot? Don't ask! I couldn't seat the ball because of the bore being badly fouled. This meant removing the breech plug, dumping the powder charge and forcing the ball and OP wad out the muzzle with my cleaning rod (broke a brass jag off in the rod too!). It took at least 15 mins. before I could reassemble the rifle, brush out the bore, and take the 6th shot. I should never have done it as that one landed 2 3/4" below the group's center.
While the bare ball test was interesting, it was only mildly satisfying since I didn't get the tiny groups I was hoping for. It also showed that, with a properly fitted ball and over powder wad, you can achieve a good, if not excellent degree of accuracy in spite of the absent patch. However, bore fouling was a constant problem and had to be dealt with, requiring even more attention than I gave it
Today's range test results: Actually, I wanted to test .490" (.492") RB's with 2 different patch thicknesses, .018" & .021" before I tried the bare balls. Using 55grs. Diamondback FFg and patches wetted with 1 Ballistol : 6 H2O, I got a1 3/4" x 1" 6 shot group with one patch and a 1 1/8 x 5/8" group with the other @ 50 yds. If I ignored the high shot from the 1st group, it would have measured 1" x 1/4". Bore fouling and subsequent reloading was fast and easy, but I did notice that the bbl. needed as many as 5 fouling shots to settle it.
The bare balls were another story and only a partially successful one at that. The nominally .518" RB's, which originally were .530" were dipped in a hot beeswax - Crisco mixture, as were the 1/4" felt wads I used under them. For this test, I used 60grs. FFg also @ 50 yds. I also wiped the bore between shots with damp patches from the first test (above). My efforts, however, were not exactly rewarded with a small group: a 6" pattern would be a charitable description, although 2 shot (out of 5) did touch. Next, I trimmed the petals off 6 MMP High Pressure (HP) sabots, saving only the base section for use as an over powder wad. I seated them with the concave base toward the powder charge. The naked .518" balls were then seated atop the improvised OP wad. I damp swabbed the bore after firing each of these as well. The result was quite good, especially when compared to the bare ball, felt wad combination. 5 shots went into a 3/4" x 2" group. What about the 6th shot? Don't ask! I couldn't seat the ball because of the bore being badly fouled. This meant removing the breech plug, dumping the powder charge and forcing the ball and OP wad out the muzzle with my cleaning rod (broke a brass jag off in the rod too!). It took at least 15 mins. before I could reassemble the rifle, brush out the bore, and take the 6th shot. I should never have done it as that one landed 2 3/4" below the group's center.
While the bare ball test was interesting, it was only mildly satisfying since I didn't get the tiny groups I was hoping for. It also showed that, with a properly fitted ball and over powder wad, you can achieve a good, if not excellent degree of accuracy in spite of the absent patch. However, bore fouling was a constant problem and had to be dealt with, requiring even more attention than I gave it