MY ramrod with the cupped head on it leans against a corner wall in my closet. I use a solid range rod to load and clean the gun, with a flat faced jag on it. It is much closer to bore size than the cupped head, and it does not allow the edges to curl on those OS cards. That was one think I wanted to know before I finished setting up my loading equipment, as I didn't want to lose shot, or have the shot column in one barrel move forward when the other barrel was fired.
I understand you're using the nitro cards, but I would think that using 2 OS cards on top of any RB would hold it in place just as well as the thicker Nitro card. That is the one thing about Jim Rackham's system that caught my eye, and got me excited enough to try it.
I agree with Roundball that I would not use 7 1/2 Shot to fill out my patterns, as the shot is too light. It will break clay targets out to 40 yards, of course, but those are much different than the neck of a turkey.
I think you would have to hit that turkey with 2 times the number of pellets at 30 yds to kill it as you would using #5 shot, my preferred shot for heavy birds, to get the same ft. lbs. of energy on the neck.( The Lyman shotshell Handbook shows a MV of 1135, and pellet energy for 7 1/2 shot at 3.58 ft. lbs., compared to 7.35 ft. lbs. for the same velocity and #5 shot. At 20 yds. pellet energy drops to 1.91 for the 7 1/2 shot, and 4.42 ft. lbs. for #5 shot. At 40 yds, ( to support Roundball's observation), pellet energy for the 7 1/2 shot is down to 1.17 ft. lbs. per pellet, while the #5 shot retains 2.92 ft. lbs., almost 3 times the energy left in the 7 1/2 pellet at that distance! And, to also support Roundball's observation, his #6 shot retains 2.08 ft. lbs. of energy at 40 yds, almost twice what the 7 1/2 shot pellet does at the same range, with the same muzzle velocity. )At 20 yds, the #6 pellet retains 3.19 ft. lbs. of energy, and eight of those pellets on the neck and head of a turkey at that distance is generally going to kill that bird. To have the same killing power, with 7 or 7 1/2 shot pellets at 20 yards, you would have to get 12 hits on the head and neck. Using #5, only 6 pellets would have to hit the head and neck, Half of what you are now using.
Since #7 is not a shot size that is commonly used here in the Sstates( you can buy it, but its more available in Europe where they shoot International Clay sports with it, but its a special order item, and jobbers don't always have it in stock. Its worse than ordering #5 shot, by comnparison. I have seen it only once at a jobber's warehouse, and didn't buy it, simply because I didn't have any reloading information to use to load my hulls with it, and would have had to fudge the data for 7 1/2 and 6 shot sizes.
Doing a little extrapolation of the data, since the tables only give pellet energy at muzzle, 20, 40 and 60 yds, in order to derive a pellet energy at 30 yds, I get pellet energy values of:
#7 1/2 = 1.54 ft. lbs. per pellet at 30 yds.
#6 = 2.64 Ft. lbs. per pellet at 30 yds.
#5 = 3.67 Ft. lbs. per pellet at 30 yds.
Using Roundball's proven performance( he did kill two birds this Spring with one shot each!)as a bench mark, to establish how many pellets have to hit a Turkey's head and neck to have a clean kill, at 40 yards, 8 pellets would deliver 25.52 ft lbs. of energy, using his #6 shot size.
To deliver that same energy at 30 yds, you need to hit that head and neck with approx. 7 #5 shot pellets, 9.4 #6 pellets, and 16.2 #7 1/2 pellets.
That is an amazing difference in pellet performance for pellets that are so close in diameter( The Rule of 17 allows you to subtract the shot size number from "17" to get the diameter in hundredths of an inch: ie, #5 = .12, #6 = .11, #7 = .10, while #7 1/2 = .09.5 " in diameter. )
Oh, I consulted the only table I have found on Black Powder velocity, in Greener's book, THE GUN AND ITS DEVELOPMENT, to find a 3 dram load of 1 1/8 oz. of #5 shot is listed at 1127 fps., 5 yds in front of the muzzle. That is pretty close to the 1135 fps. velocity given in the Lyman book as " Muzzle velocity". 3 drams is 82.5 grains of powder, as close as I can get to the 80 grain load mentioned by both Fusil, and Roundball. 3 drams of powder with a 1 1/4 oz. of shot actually reduces the velocity to 1119 fps. for #6 shot, so loading more shot with the same powder charge simply reduces the muzzle velocity and subsequent velocities.
Since its important for pattern uniformity to stay under 1100 fps., the speed of sound, so that the pellets are not buffeted by shock waves, and air currents that are created at the sound barrier, Its important to stay as close to that 1100 fps. figure as you can.
According to the Greener tables, that 3 dram, 1 1/4 oz. load of #6 shot that is traveling at 1119 at 5 yds, is already down to 1091 fps. at 10 yards, below the speed of sound. Since time lapse photograph ( and actual test targets) shows that the shot pattern does not begin to open up until 9 feet( 3 yds)in front of the muzzle, regardless of velocity, shot size, or weigh of the shot load, or barrel length, and at 10 yds, is generally only the size of a large soft ball , Sound Barrier disturbance is probably minimal with that load, or loading more shot with the same 3 dram powder charge.
What the actual velocity is that Roundball gets from his gun and that load can only be accurately measured by a chronograph. To protect the chronograph and get an accurate velocity reading, all one needs to do is make a coin wrapper type shot cup, but leave it long, so that the ends can be folded over the top of the shot load, to make a fragmenting " slug " instead of a shot load that spreads. Since you are generally going to set the chronograph 5-10 feet, sometimes 20 feet in front of the muzzle, The slug will stay together and pass over the screen as one projectile, giving an accurate reading of the velocity of the shot at that short distance from the muzzle. Since muzzle velocity is measured at some short distance from the muzzle on any gun, to keep expanding gases from going over the screens, and giving false readings, the results one obtains will be fairly close to published data. If it isn't, its because there is something different in the load that is causing a loss of velocity.
For instance, My first test of my .20 ga. fowler gave a disappointing 800 fps. using 75 grains of powder( 2 3/4 drams) and a 3/4 oz. round ball instead of a 3/4 oz. load of shot. I found out that my barrel is oversized, and ordered some 19 gauge over powder and over shot wads, and the velocity went immediately up to abou 1060 fps, a substantial gain, which also brought the POI up on my 25 yd. target. about 6 inches.
Roundball's gun, this year, used a barrel that he had Jug Choked, and I have no doubt it made a difference on his longer shot. He is to be given credit for his research, and wisdom in having one barrel jug choked just to use for turkey hunting. He is a good enough hunter to get birds within 20 yds, but he gave himself an edge in case some ole Tom decided he wasn't going to be sweet talked into coming in that close. :hatsoff:
