Larry Zornes 20 ga Loads

[Top Jaw]

Recently picked up a 20 gauge smooth rifle that a friend of mine Marvin Berry completed for me. Loosely based on an iron mounted version of RCA #25, in figured walnut.  It has a Larry Zornes 42” oct to round barrel that I’ve had for awhile. 

This is my first flintlock smoothbore. Any of you guys have a pet load you like using in this barrel for shot and round ball?  I used some .595 round balls and pillow ticking over a fiber wad, with 70 grains 3F (had no 2F at the time, but now I do).  I got what I considered decent groups with no rear site the first time out with that, but always looking to learn.  Barrel appears to have a slight choke in it, at least during loading.

Thanks

[Craig Wilcox]

Top, that is a nice looking piece - love the "simplified" tang carving.
Don't have any load data for you, although I do have two 20-bore guns.  But sounds like you are on the right track with the 70 grn and PRB.

[Bsharp]

Very nice looking smooth rifle!

[B.Habermehl]

I think you on the right trail as far as load development is concerned. Only further experiments will tell. My own experience with a Zornes 28 guage barrel was very good. I won or placed in a number of shoots with it. My barrel is mildly choked also, perhaps only a couple of thousandths of a inch or so. I know one barrel maker that allways marks the end of the barrel blank he drills and reams from. This will be the breech end in the finished barrel as there is often some taper in the finished bore, from start to finish. BJH

[D. Taylor Sapergia]

I have found that I needed more powder than that to ring out the best accuracy potential in 20 guage.  I have found that 85 gr. of FFg GOEX and a tightly patched .600 ball gives best accuracy in my guns.

[Brokennock]

My 20 gauge smoothrifle has a colrain barrel, to me it feels a little tighter at the muzzle but I can't say it is deliberately "choked."
What I can say is that both of my 20 gauge guns seem to shoot better with looser loads compared to a rifle. Seems like the tighter I go, especially with the smoothrifle, the worse the groups get. 80 grains of 3f with a .595 ball and .010 patch shoot very well. But, a load of, 80 grains 3f, thin card, lubed felt wad, .610 ball, held in with another thin card shoots even better.
Then things get even more odd. I needed a load less than 75 grains to comply with a local club's trail walk rules.
Turns out, 65 grains 3f shoots as well or better, with patched .595 ball, or the wad and ball sandwich described above, or even a paper cartridge.
Admittedly I have not tried this load past 50 yards. I don't have a 75 yard backstop and my vision makes 100 yard shooting with a smoothbore flintlock impractical, I wouldn't shoot game that far out with a smoothbore so I don't bother at the range.

[martin9]

65 grains of 3f is my pet load for my 20 also. I started higher and went all the way to 120 with 2f. the 65 grain loads shoots the best out to 70 yards or so...haven't tried it further than that. I use an overshot card or a hard nitro card between powder and patched ball. .595 ball and .020 patch lubed with mink oil.

[Top Jaw]

So I hear about equal volumes of powder to shot, when working up a scattergun load.  Maybe slightly less powder.  I don’t  have a shot dipper here right now to check it.  Anyone know the volume equivalent in powder for a 1 ounce load of shot?

[Top Jaw]

Found online.  1 ounce volume of shot (#9) = 67 grains of volume black powder.  So about a 70 grain powder measure can be used for a 1 ounce load of shot and for an equivalent powder charge. 

[Tony N]

My 20 ga likes 75 gr of FF and the same measure for shot

[Daryl]

Here is the list I have for the 3/8" diameter brass powder measure I have:
 50gr. - 3/4oz
 60gr. - 7/8oz
 70gr. - 1 oz
 80gr. - 1 1/8oz
 90gr. - 1 1/4oz
100gr.- 1 3/8oz
110gr.- 1 1/2oz
120gr.- 1 5/8oz

note - 7,000gr., in a pound
--------437.5gr. in one ounce
--------16 ounces in one pound
--------27.3grains in one dram
--------16 drams in one ounce

54.6gr. - 2        drams
61.5gr. - 2 1/4 drams
68.25gr. - 2 1/2 drams
75.0gr. -  2 3/4 drams
82.0gr. - 3        drams
89.75gr. - 3 1/4 drams
102.375gr. - 3 3/4 drams
109.2gr. - 4 drams

Modern shotshell boxes (usually) have "Drams Equivelent" markings.

Typo corrected.

[Brokennock]

Thank you Daryl. Great chart. I do think the 61.5 grains is actually 2 1/4 drams though,,,,,, but math and I are not friends.

[Daryl]

Tks - typo - corrected.