Ball calibers and diameters make no sense.

[Sonny from Vincennes]

I agree with making the chambers the same. Back in the day when revolvers were king in target shooting, the shooter would measure the chambers. The shooter would try to find a chamber close to the diameter of the groove of the barrel. The shooter would mark this chamber for SLOW fire only. The shooter would have plenty of time to load this one chamber. The other chambers would be used for TIMED and RAPID fire events. An interesting test on the chambers is to use a hole gage to check for roundest of the chamber. I have found many egged shape chambers which leads to flash over to other chambers if not sealed with grease or wad. I always tried have a good shear on the ball and have the shear as equal as possible around the ball for the best accuracy.

 

[earlwb]

7.62 mm equals ? .308

Is that by groove or land? .308 by land and .311 by groove. Then of course some guns had .313 to upwards of .316 groove size too. For example the 7.62 x 54R Russian cartridge. Or the British .303 is another et example.

 

[Relic shooter]

Don’t forget that the ball size will change with the type of cloth or paper you use as a patch for it. Same thing for conical bullets too. It depends on the bullet design. A hollow base bullet might be a bit smaller for a more loose fit than a solid base bullet. A target rifle might have you more forcefully swage the bullet down the barrel for a tight fit too.

Mentioning gun safes, does anyone actually make a safe that would fit long muzzle loading rifles or smoothbores?

Home Gun Safe Options;
- Flush mount in-the-bed truck boxes make excellent gun safes. Can weld shielded lock covers on them & bolt vertical or horizontal to the floor or wall. A friend mounted his truck box below a living room window as a bench seat with cushions & covered the front & sides with paneling.
NOTE; for extra fireproofing concerns use sheetrock to line the interior or exterior surfaces.
-I've also converted closets into gun safes by replacing the doors with a flush-mounted 3/4" panel hinged by heavy duty steel piano hinge & attaching a lightweight bookcase to conceal the whole affair.
**For hidden latches; I've used gate-latches that are tripped by a hidden rod or wire via a tiny hole drilled directly under a shelf. Can put a small loop in the wire latch or attach to a low interest object on the shelf.

**My "latest & best completely concealed latch" is a sliding steel pin enclosed in an aluminum tube that is open & closed by a strong magnet attached to back of a picture frame that sets on a shelf. Sliding the picture frame to the right 2" opens & to left closes. I screwed a brass plate to the door jamb to provide a secure receiver for the locking pin.

 

[Sonny from Vincennes]

To answer your question 7.62 mm equals 0.300 inches. To say any more I need your caliber. A lot of military people say 7.62 they really mean 7.62 NATO. But there are a lot of 7.62 calibers. The 7.62 NATO should have a 0.300 bore and a 0.308 groove. This is a military caliber and you will find these dimensions on a military specification (mil-spec) drawing. On civilian cartridges you can find the dimensions on Sporting Arms and Ammunition Manufacturing Institute (SAAMI) web site. This is a US manufacturing site. For European made cartridges go to Commission International Permanente (CIP). Unless you can read a foreign language, select (EN) for cartridge dimensions and the dimensions are in millimeters. Per SAAMI site, the 303 British has a 0.303 bore and 0.314 groove. Always go to the SAAMI site to find the dimensions for a US caliber.
Good Luck and have a good day

 

[beardedhorse]

Since I picked up a used Ruger Old Army I find I need to buy or borrow a .457 mold. Lee used to make them in double cavity in aluminum. Not sure if Lyman ever did but even used Lyman steel round ball molds approach $100.00 by the time you pay for shipping. .454 work fine on Uberti Remington New model Army. Not as tightly shaved as .451. May try .457 in it.

 

[Sandro_Ventania]

Eu não faço cofres. Eles não são grandes o suficiente. Tenho dois armários inteiros que foram protegidos e securitizados e usados para armazenar com segurança apenas as armas de fogo. A munição é armazenada separadamente em condições seguras e protegidas em um andar totalmente diferente. O que eu realmente preciso é de uma casa nova localizada em um estado livre, não de alguns malditos cofres de metal para armas!! Desculpe.

And i, a country new!

 

[Sonny from Vincennes]

I got some time so I looked up the 7.62X54R. The 7.62 mm = 0.300 inches for the bore and the 7.92 mm = 0.312 inches for the groove. This information comes from the Commission Internationale Permanente (CIP) site. Go to Table of Dimensions of Cartridges and Chambers (TDCC). The dimensions are in millimeters so convert to inches. This organization is mandatory for any one making guns and/or ammunition in Europe. Sporting Arms and Ammunition Manufacturing Institute (SAAMI) is voluntary for the people making guns and/or ammunition in the US.

 

[wiscoaster]

Eu não faço cofres. Eles não são grandes o suficiente. Tenho dois armários inteiros que foram protegidos e securitizados e usados para armazenar com segurança apenas as armas de fogo. A munição é armazenada separadamente em condições seguras e protegidas em um andar totalmente diferente. O que eu realmente preciso é de uma casa nova localizada em um estado livre, não de alguns malditos cofres de metal para armas!! Desculpe.

I said THAT?!?! Wow, that's the fastest I've ever learned Portuguese!!

 

[Sonny from Vincennes]

I just received an answer from the Lyman people about muzzle loading arms dimensions. They said there is NOT a web site even close to the SAAMI or CIP web sites. I know these sites had problems with the manufactures in the US and then in Europe agreeing on dimensions and limits. On top of that, we have both the english and the metric systems of measure. We have cartridges that go between the SAAMI and CIP. Both of these web sites date back to 1913 and 1914 respectively. I can understand the difficultly the manufactures would have dealing with the nominal and tolerance dimensions for the black powder guns. I guess the black powder and the substitutes are not as temperamental as smokeless powder. If problems gets serious enough that people get hurt or killed, then a web site will be developed. That is what happened to create the SAAMI and CIP.

 

[wiscoaster]

.... I guess the black powder and the substitutes are not as temperamental as smokeless powder. ....

I think you're on to something there. When I got into black powder I was surprised at the wide range of loads a shooter could use in a given gun.

 

[Sonny from Vincennes]

I have found a lot of interesting things about black powder and the guns. I am retired and have the time to do research and testing. I have even went to the historic sites for information. The NPS has living history people who really get into these subjects and tries to duplication the methods of years ago. These help to make sense of how history happened. I served on cannon crews and drilled with firelocks with dummy ammo of course. I have seen how barrels and the total guns were made. All of this information makes the black powder guns easier to shoot.

 

[Some_Mook]

I got some time so I looked up the 7.62X54R. The 7.62 mm = 0.300 inches for the bore and the 7.92 mm = 0.312 inches for the groove. This information comes from the Commission Internationale Permanente (CIP) site. Go to Table of Dimensions of Cartridges and Chambers (TDCC). The dimensions are in millimeters so convert to inches. This organization is mandatory for any one making guns and/or ammunition in Europe. Sporting Arms and Ammunition Manufacturing Institute (SAAMI) is voluntary for the people making guns and/or ammunition in the US.

Just to add to the fun of how crazy 'caliber' vs actual measured diameters is, the 7.62x54R, which was developed by Russia for their 1891 'three line' rifle was originally called...


wait for it...



the 'three-line cartridge model 1891'


Since the Russians referred to a bore diameter as being expressed in 'lines' and a line represented a distance of 100 thousandths of an inch, a three-line rifle had a bore of .300" (or 30 caliber). So a Mosin-Nagant (Officially a 3-Line rifle M1891) is a 30 caliber rifle. Interesting that the Russians would employ a fraction of an Imperial measurement to designate as a 'line' but then they had to go and fudge up distance in yardage by using a Arshin to represent exactly 28 English inches. If you are shooting at a Target 100 yards away, it is about 128 Arshins away, but only 91.44 meters.

For more fun, a Mark 6 naval gun such as was employed on the North Carolina-class US battle ships would properly be called a 16/45 (16 inch / 45 caliber) gun. The bore diameter was 16 inches. The caliber was determined by the length of the bore divided by the bore diameter (or how many distances of diameter stacked end-to-end would equal the bore length). The Mark 6 bore length was 720 inches. 720 divided by 16 =45, so the gun was a 45 caliber.

If we used that method for standard carry firearms, a 42 inch long bore length with a .69 bore diameter would be a 61 caliber (60.869 rounded up, since we always round up because bigger is better). If we increased the length of the barrel bore to 44 inches, then we would have a 64 caliber. Think of the fun that could be had explaining how two guns with identical bore diameters would actually be two different calibers because they did not share the same bore length.

A Colt Navy revolver with a 5" barrel would be a 14 caliber, but if it had a 6 inch barrel it would be a 17 caliber.

I guess my point with all this nonsense is that, for the most part, it is all nonsense.
But only because the Europeans with their pesky Metric System screwed it all up. I blame the French.

 

[TFoley]

Is that by groove or land? .308 by land and .311 by groove. Then of course some guns had .313 to upwards of .316 groove size too. For example the 7.62 x 54R Russian cartridge. Or the British .303 is another et example.

Yup.

In modern firearms the hole is made first, and then the grooves.

If the bullet just fit the holes, then there would be no spin.

So the bullet is made bigger, and the jacket engages in the grooves.

Mostly.

 

[Sonny from Vincennes]

The gun world is very interesting. I enjoy traveling around and listening to the living history people and writing the NRA tech people. There is a lot to be learned about guns. I have used the NRA for several years to answer questions from my students.

 

[earlwb]

I forgot to mention that in the old days when everyone that had been out in the wilderness went to a rendevous or visited a town that had a gunsmith they would get their rifle's bore freshened up. The gunsmith would maybe even bore it out a little and cut in new rifling too. Plus ream out their bullet molds to fit as well. Thus many of the antique rifles we see today may have really odd calibers to them. That is where maybe we likely got .52, .54, .62 etc calibers from originally. So way back then it was something of a free for all with calibers.

 

[Sonny from Vincennes]

I was told that the reason the front sight was back from the muzzle was to allow for recut and crown because of muzzle wear from ram rod.