Harpers Ferry 1803 info help

[JBrandon]

Friends,
I just acquired a Navy Arms / Zoli 1803 Harpers Ferry. Nice gun, seems accurate the few shots so far.
Can anyone tell me when it was made, and rifling twist rate? Seems to have a serial number 8858
It's .58, although I can't get it to take a .575 ball, just .562 so far.
Also, although seems accurate, shoots very low at 50 yd. If I want to sight on it, I pretty much have to have the POI resting on the top of the barrel at the bottom of the front blade. So I can't really lower the foresight, need to have higher rear sight somehow.

 

[Grenadier1758]

The 1803 by Zoli was made in Italy. It should have an Italian proof stamp on the barrel. These are the codes from 1945.

Italian Date Codes​
1945 = 1​	1967 = XXIII​	1989 = AU​
1946 = 2​	1968 = XXIV​	1990 = AZ​
1947 = 3​	1969 = XXV​	1991 = BA​
1948 = 4​	1970 = XXVI​	1992 = BB​
1949 = 5​	1971 = XX7​	1993 = BC​
1950 = 6​	1972 = XX8​	1994 = BD​
1951 = 7​	1973 = XX9​	1995 = BF​
1952 = 8​	1974= XXX​	1996 = BH​
1953 = 9​	1975 = AA​	1997 = BI​
1954 = X​	1976 = AB​	1998 = BL​
1955 = XI​	1977 = AC​	1999 = BM​
1956 = XII​	1978 = AD​	2000 = BN​
1957 = XIII​	1979 = AE​	2001 = BP​
1958 = XIV​	1980 = AF​	2002 = BS​
1959 = XV​	1981 = AH​	2003 = BT​
1960 = XVI​	1982 = AI​	2004 = BU​
1961 – XVII​	1983 = AL​	2005 = BZ​
1962 = XVIII​	1984 = AM​	2006 = CA​
1963 = XIX​	1985 = AN​	2007 = CB​
1964 = XX​	1986 = AP​	2008 = CC​
1965 = XXI​	1987 = AS​	2009 = CD​
1966 = XXII​	1988 = AT​	2010 = CF​
Prior to 1945 date codes were in Roman numerals and included the month and the last two numbers of the year, so January 1922 would be rendered IXXII.​

Now as to loading a round ball. Zoli would have used a barrel from their 58 caliber musket line and the land to land diameter is probably close to 0.575". A 0.575 ball with any size patch is not likely to fit. How many lands does it have? Do you have a digital caliper to measure the inside diameter of the bore? More than likely, your 0.562" ball will be the best size for that barrel. My 1803 has a 54 caliber Colerain Barrel, so my experience won't be of much help.

 

[FlinterNick]

I have an. 1803 with a 7 groove Getz barrel at .54. I use a .535 ball in a paper cartridge with the ball end greased. Like a Baker Rifle Cartridge.

I owned a Zoli .58 1803 years back. Stock had some nice drop in it, the barrel was a match grade at .58 with 3 lands and grooves, military style that you’d see in most Civil War Muskets. Can take both a round ball and a conical round. Has some incredible range on it but on the down side, the zoli 1803 isn’t very historically accurate.

 

[TreeMan]

Once you find an accurate load combo start filing down your front sight to raise the point of impact. File just a little at a time, shoot a few rounds to see where it hits. If it’s still shooting low file a bit more. Continue until you get it where it needs to be. Be sure to file just a little at a time then check where it hits. Use a small hand file not a dremel tool. The dremel takes off too much too fast.

 

[JBrandon]

Thanks for the help guys. It has AA in a square on L side barrel near breech so I guess that's 1975 by Grenadier's chart. Do you know the rifling twist rate?
I need to get a new rear site. If I file down the foresight, I'll be down on the barrel before I get aimed high enough - the rear sight is just 5/32" above barrel. I made a temp sight out of a slip of copper that I glued on to the real sight, doubled its height to 20/64" and that got me up on to paper.
Thanks, John