Trivial question
- Thread starter Timberlord
- Start date
- Location
- Abbotsford, BC
It probably had something to do with what was in their tea that day 
But you're right, a quick search brings the .303 Brit up as a 0.311 diametre bullet (7.9x56.4mm) (which I knew) and listed as a 7.7x56mm rimmed (which I didn't know the actual metric designation before). It says that its basically the same as the difference between a .38 special and .357 magnum, the measurement being from bore to bore vs land to land following older blackpowder practice. That and ".303 Brit" sounds so much better than ".311 Brit"! LR
But you're right, a quick search brings the .303 Brit up as a 0.311 diametre bullet (7.9x56.4mm) (which I knew) and listed as a 7.7x56mm rimmed (which I didn't know the actual metric designation before). It says that its basically the same as the difference between a .38 special and .357 magnum, the measurement being from bore to bore vs land to land following older blackpowder practice. That and ".303 Brit" sounds so much better than ".311 Brit"! LR
Last edited:
Pick a number!
Sometimes things just end up an arbitrary size or distance for strange reasons.
I was watching the space shuttle go up on TV. It has honking big solid rocket boosters mounted each side. I was wondering why the rockets were long and thin instead of short and fat, which would give greater boost over a short period of time, which is what boosters do!
The boosters are as fat as they can be because they are built in Utah and transported by railroad to Florida to the launch pad. If the boosters were any fatter there would be problems with them passing through a tunnel in a mountain on route.
So the rockets are limited by the size of the railroad tunnel which is governed by the size of the train. Standard rail guage in North America is 4 feet 8-1/2 inches. Why such an odd distance? It is the standard guage used in England and was brought over with early rail stock and locomotives.
The standard Brit railguage is based upon the standard width of a tramway which used a standard width road wagon axle. The dimension was a standard and adhered to because if a wagon was built with rims wider or narrower, the wheels wouldn't ride in the grooves worn in the road and would quickly be destroyed. So 4 feet 8-1/2 inches was used for centuries.
So where did this odd dimension come from? The first Brit road network was built by the Romans. 4 feet 8-1/2 inches is the standard width of chariot wheels. A chariot was built to be pulled by one horse.
So there you have it. The size of the booster rockets on the space shuttle, arguabley one of the most technological advanced forms of transportation, was determined thousands of years ago by the width of a horses arse.
Sometimes things just end up an arbitrary size or distance for strange reasons.
I was watching the space shuttle go up on TV. It has honking big solid rocket boosters mounted each side. I was wondering why the rockets were long and thin instead of short and fat, which would give greater boost over a short period of time, which is what boosters do!
The boosters are as fat as they can be because they are built in Utah and transported by railroad to Florida to the launch pad. If the boosters were any fatter there would be problems with them passing through a tunnel in a mountain on route.
So the rockets are limited by the size of the railroad tunnel which is governed by the size of the train. Standard rail guage in North America is 4 feet 8-1/2 inches. Why such an odd distance? It is the standard guage used in England and was brought over with early rail stock and locomotives.
The standard Brit railguage is based upon the standard width of a tramway which used a standard width road wagon axle. The dimension was a standard and adhered to because if a wagon was built with rims wider or narrower, the wheels wouldn't ride in the grooves worn in the road and would quickly be destroyed. So 4 feet 8-1/2 inches was used for centuries.
So where did this odd dimension come from? The first Brit road network was built by the Romans. 4 feet 8-1/2 inches is the standard width of chariot wheels. A chariot was built to be pulled by one horse.
So there you have it. The size of the booster rockets on the space shuttle, arguabley one of the most technological advanced forms of transportation, was determined thousands of years ago by the width of a horses arse.
stencollector
CGN Ultra frequent flyer
- Location
- shilo MB, the armpit of Canada
I bought an Enfield off an old guy last year, and the barrel had been cut a bit shorter, but still had the bayonet lug and front site. So maybe an inch had been removed. I asked the guy why? He told me it would fit into the cupboard.
Sometimes these things are arbitrary, but often there is an underlying reason that made sense at the time.
Sometimes these things are arbitrary, but often there is an underlying reason that made sense at the time.
"....303 inch bore..." And it's still considered to be a .30 calibre.
"...are as fat as they can be because..." The depth and width of the Panama Canal was determined by the size of U.S. Navy battleships. Ever since the size of USN warships(except, of course, for Nimitz Class CVN's) has been determined by their ability to go though there.
"...are as fat as they can be because..." The depth and width of the Panama Canal was determined by the size of U.S. Navy battleships. Ever since the size of USN warships(except, of course, for Nimitz Class CVN's) has been determined by their ability to go though there.
Lee Enfield
CGN Ultra frequent flyer
- Location
- Republic of Alberta
Technically a .303 has a .303 bore and .311-313 groove depth where-as a .308 has a .300 bore and a .308 groove depth.
However, if someone can just explain to me how the Brits named their several various .450 and .455s with the same bore & groove spec's as the .476 cartridges....
The bore dimensions were determined in a bunch of experiments when Major Rubin of the Eidgenossische Waffenfabrik Bern was working in England...... so we can safely blame the .303 bore diameter (actually an ideal dimension, as actual barrels were accepted as tight as .301" for the Lee rifle and some as tight as >299" for the Ross) on a Swiss! Cheesy, or what?
Still, it's been naturalised long enough that we can safely say that it IS the BRITISH .303. So there!
If you want to get really ripped out of shape, consider the guy in the red coat and white pith helmet as he loads his Martini-Henry to take out the barbarian hordes who are approaching with their tulwars and jezails ans assegais and suchlike neat things. He drops a round into the chamber, slaps the lever shut and announces to the world, "I am an Englishman!".......... which equates to "Ic beon ein Aenglishmanna!"..........
which means, "I am a German!"
Oh, what a wonderful world we live in! On that note, Happy New Year all!
Still, it's been naturalised long enough that we can safely say that it IS the BRITISH .303. So there!
If you want to get really ripped out of shape, consider the guy in the red coat and white pith helmet as he loads his Martini-Henry to take out the barbarian hordes who are approaching with their tulwars and jezails ans assegais and suchlike neat things. He drops a round into the chamber, slaps the lever shut and announces to the world, "I am an Englishman!".......... which equates to "Ic beon ein Aenglishmanna!"..........
which means, "I am a German!"
Oh, what a wonderful world we live in! On that note, Happy New Year all!
Here's my question: How can you measure a 5 groove barrel for land and groove depth when neither the lands or grooves are on oppiste sides?
I always wind up measuring land-to-groove...
My 4 groove Mosin was so simple to slug and measure.
I always wind up measuring land-to-groove...
My 4 groove Mosin was so simple to slug and measure.
- Location
- pallisers triangle
now that is a classic.and explains a lot....... you dont mind if i use that one from time to time do you???
It is very easy to take a set of barrel bore gauges and run through larger and larger ones until one won't go. This is how you determine bore diameter.
Groove diameter is more difficult to measure.
It is handy to note that the typical groove is 4 thou deep or 8 thou side to side. So a 300 bore is 308 to the bottom of the grooves. Or a 303 is 311 to the bottom.
Anyway, 303 refers to bore diamter. But why they chose 303 instead of 300?I can only assume is because they were Brits. I like the metric approach to half milimeter steps in calibers.
Groove diameter is more difficult to measure.
It is handy to note that the typical groove is 4 thou deep or 8 thou side to side. So a 300 bore is 308 to the bottom of the grooves. Or a 303 is 311 to the bottom.
Anyway, 303 refers to bore diamter. But why they chose 303 instead of 300?I can only assume is because they were Brits. I like the metric approach to half milimeter steps in calibers.
you can measure bore diameter very precisely with plug gauges. Groove diameter you can get with a micrometer and a set of hermaphorodite calipers, which sound odd but do not sell for a lot of money. Insert the calipers into the bore; one leg will stand on a land, the other in a groove. Zero, take your measurement and lock, then remove calipers and meaure with the micrometer.
And be sure to have fun while you're doing it; that's what this is supposed to be all about.
And be sure to have fun while you're doing it; that's what this is supposed to be all about.
