Lessons Learned from my Trade Gun

[Maven]

I had an yen to fire my GRF 20ga. trade gun today, ostensibly to fine tune loads for it, but really to eliminate certain variables, and naturally, to have a good time while testing it. Thanks to Waksupi, northmn, mooman, D. Taylor Sapergia et al, I've got the powder charge down pat: 85gr. FFg. However, ball diameter and patch thickness have always been a bit of a problem, as has the recommendation to use felt over-powder and over-ball wads and even cardstock wads. The wad thing didn't work at all. Yes, I hit paper, but the hits were at 9 o'clock & 3 o'clock and 6" apart @ 25yd. What I'm starting to realize is that the ball/patch relationship is very different for a smoothbores as contrasted with a [BP]. While a tighter ball/patch combination generally works well in my rifles, the trade gun does quite well with a .014" pillow tick patch* and a .597" RB cast from a Jeff Tanner mould (supposed to be .600"). This worked very well as groups were under 2" @ 25yd. If the .014" patch works as well with my .600" Dixie mould I'll be very happy.
In sum, I learned that (1) a smaller dia. RB AND a thinner patch may be the better way for my gun; and (2) this gun doesn't do so well from a rest. Rather, I kneel with my left elbow on the bench and right knee on the ground.



*I use the red striped tick to distinguish it from the thicker dark blue striped material.

[Baron von Trollwhack]

Think of a caseless BP cartridge loaded in your barrel:85 grains FFg, thin durafelt wad, patched RB for primary seal and to keep the ball tight on powder and wad.

If the felt or a substitute card stock or a thick wad does not work, dispense with them. Then work on the patch thickness,and lube, the ball is a given and you like the charge.

My 20 likes 90 grains FFg Goex, a .604 RB and a 0.020 canvas patch lubed with a BW/tallow/vaseline (essentially Emert's lube) mix on the barrel side, and a good slurp of spit or water on the ball side. Pre lube first, then wet when loading. I found a tighter patch fit and a bit more lube and wetting to shoot better at 50 & 60. Oh, yes, a short starter too. BvT

[Maven]

BvT, I'll take your suggestion re patch thickness to heart when I move my target to 50yd., which I hope is soon. Before I do that, however, I need to see if the thinner (.014") patches will -> repeatable results @ 25yd. In the process I also hope to eliminate the largest RB (.610", Rapine*) and just work with the Tanner and Dixie, especially the former. And yes, I keep several short starters handy!


*disappointing results so far

[waksupi]

Awaiting your results. I used a thin muslin patch for years in the trade gun with a .600 ball, then went to .595 and pillow ticking, as I would occasionally see a patch with a hole in it, with the thin stuff. You will find you best load eventually. I shot my fowler offhand this week, and was getting around a 6" group at 50 yards. If I could see, shoot without jerking the trigger, and flinching, I'm sure it would do better. Like you, I can not shoot any of my smoothbores well from the bench, so do off hand work, and concentrate on calling my shots.

[Maven]

"If I could see, shoot without jerking the trigger, and flinching, I'm sure it would do better. Like you, I can not shoot any of my smoothbores well from the bench, so do off hand work, and concentrate on calling my shots."

I hear ya, Ric! Btw, my last 2 shots were offhand with the 1x-fired patches mentioned above and I managed to obliterate 2 orange clay fragments @ 25yd. Also, while cleaning the gun I managed to get some solvent in the trigger mortice, which got me thinking about the trigger itself. In short, I pulled it when I got home and polished its surfaces (being careful not to remove much metal, of course) and the lock sear as well.* Now that it's reassembled, the trigger pull is much smoother, if not easier.


*I took a digital photo of the lock innards over the winter, disassembled it, and polished the inside surfaces of the lock plate with a Cratex wheel in my Dremel tool. The photo was a great help in [correctly] reassembling the lock.

[northmn]

I ran into something similar in that my 20 bore actually shoots better with a 015 patch over a thicker one. I think with a smoothbore you have to be more careful about damage to the ball when loading it. I also ahd a concern over the molds as my Dixie Mold did not cast a true round ball but was about 005 off. I ordered a Lee and got down to about 002. I get pretty good accuracy out to 75 yards with my combo but also take care in loading with the parting line up to compensate for out of round. I am about 90% sure that a smooth bore needs extra care in loading over a rifle. My smoothbore also has rifle sights which for roundball makes a difference, but is not legal in competition. It would take a lot of practice to get a 6" group offhand with a rifle and only a front sight.
Another trick I ahve used is to put a small light spring on the trigger so that the spring always puts tension against the sear. It saves me a lot of time fitting and eliminates all slack. They used to do that in old shotguns.

DP

[Maven]

DP, My situation re molds & RB diameter is similar to yours, with just a bit of difference. It's the Dixie mold which casts a rounder and actual .600" RB. The higher quality and priced Rapine casts a slightly out-of-round .610" ball that's 9 - 10 gr. heavier than the Dixie, but it's easier to use. The Tanner mould cast consistently round .597" balls which seem also to be quite accurate...at 25yd. I'm also thinking the Rapine ball is the least accurate of the 3.

[northmn]

One thing I noticed using my 20 bore was that my groups tended to be horizontal rather than vertical. A 4 inch group might be 2" X 4". This seemed pretty standard. Rifles, like my 25 often give a vetical grouping. I feel it may be more sensitive to powder variations. I tend to believe that the horizontal is due to imperfections in the ball/patch combination. The 58 rifle tends to shoot a "square" group as the variations are about the same in both directions. This I attribute to imperfections in the shooter. I also sight in my smooth rifle at 75 yards. I do recommend you test at at least 50 yards as 25 yards does not always prove as much. I do understand that it is easier to find a place to shoot at 25 yards. Just a suggestion.


DP