How do you determand the cal of a gun

[old]

Ok so here is what I need to figure out. On Monday a guy will be bringing me a single shoot black powder hand gun. He does not know what cal this thing is so how do you go about determining cal of it when you have one that does not have that stamped on the gun any place.
Thanks
Yes I figure you can measure the barrel some how but once done how do you know with those numbers what it is??
 

[Robert Mull]

Google Caliber and read definiation under wikipedi
 

[Mike M]

Mic it. if it measures .450 then its a 45 cal. and so on.
Black powder shouldn't have too many choices.
 

[old]

Google would be fine if I was not on dial up. Every time I try to Google something it takes forever and two days to get any place then it sets up 20K sites to sort out
 

[farmer boy]

Is this site actually faster than Google for you? When I was on dial-up, this site was the 2nd fastest site next to Google search. Google was dang fast as far as dial-up goes.
 

[old]

Y-T is one of the fastest sites I go to but maybe it is because I am on here so much so the computer knows where it is going LOL
 

[delawarbill]

Old,

Remember, usually in the US the bore diameter is measured in the grooves as opposed to the lands. The lands are the raised areas resulting from the rifling operation. To determine the actual cartridge, you should do a chamber casting. Let me know if you want me to elaborate on that.
 

[RN]

Black powder caliber standard is land to land measurement. works best on even number of lands and grooves- but the diameter of land height is same on the odd number groove like Enfield M53, etc. Pistol bore measure with inside caliper or get to muzzle and use a ruler on top of land and hopefully opposite land. A land to land of .44 gets a 44 caliber- and with usual patch means use a .425 to .430 ball. Old cut standard was 6 to 8 thousands groove so a difference of .012 to .016 groove diameter to land was normal. Musket groove during civil war was shallower on springfields like Colt 1863 and some single shot Dragoon pistols of same .57 caliber-- .004/.005 difference. Lots of modern made replicas use a shallower groove- more like current standard of .003/.004- since they"re being made with "modern" tooling. Dixie had some .35, .36, .38 calibers of pocket pistols from varying makers- english, spanish, Italian. and they did vary from deep cut to shallow.
 

[old]

I did a wax cast on that Argentine rifle I had and that worked pretty well but on a black powder hand gun not sure how I could do that and get it back out of the bore
 

[DiyDave]

There is a silicone (I think) material, that shrinks just a little, on drying, that law enforcement uses to cast the ID of guns that have been intentionally damaged, at the ends of the barrels. I saw it on one of the How catch-em cop shows, on TV. If you have a Cop Buddy, ask about it, or google it.
 

[John D Smith]

Old, first go to castboolits.com they have 25,000+ members that are experts on everything gun and more. Signup is free and you will get prompt, expert repies.
John
 

[old]

Cop and buddy in this area does not mix since about 75% of them are on the take like most in the court house. Some people call the court system in this area the Little mafia
 

[Bret4207]

[old]

You know if this works this is the easy way to get to a site when you give them a site
Gun sight

 

[old]

You know if this works this is the easy way to get to a site when you give them a site but guess I did something wrong or you did not list it right since it does not work
Gun sight