Talk:.308 Norma Magnum

Error in specifications

There must be an error in the specifications. The specifications on the right do not match the specifications in the text. —Preceding unsigned comment added by Lightmouse (talk • contribs) 11:47, 26 December 2007 (UTC)

Yup. This is common when looking for cartridge info. The sources are different and the cartridges are different. The one in the article is Norma's 200gr Vulkan bullet, the one in the info box is from cartridges of the world, unknown manufacturer (because I don't have that book to see which they used).

Since the cartridge was created by Norma we should probably use their specifications. Tengu99 (talk) 16:12, 28 December 2007 (UTC)

Thanks for the reply. You seem to know more about the topic than I do. So I will leave the correction to you. I hope you do not mind. Lightmouse (talk) 19:29, 29 December 2007 (UTC)

Well, I know a bit, but the info is gathered from other sites. I'm taking Chuck Hawks at his word that the factory loading is as he says....however, Norma's ballistics calculator (U.S.) doesn't list a 200 gr Vulkan bullet. It does list a 180 gr Vulkan bullet, so perhaps the data for that should be used instead? If you agree go ahead & change it or I can do so. It shows a muzzle velocity of 2756 fps. At 150 yds it shows a velocity of 2313 fps & energy @ 2137 ft-lbs. http://www.norma.cc/ Tengu99 (talk) 04:51, 30 December 2007 (UTC)

I think specifications on the manufacturer's website in its own language rank higher than other sources in most cases. I took a look at their website and note that it is a Swedish company. Thus I would use the metric values as primary and put non-metric in parentheses. I dug around a bit and I think the Oryx values might be relevant rather than the Vulkan but I am not sure. Lightmouse (talk) 11:35, 30 December 2007 (UTC)

In this case, what the sources show us is the existence of at least 180 gr and 200 gr variants mentioned above. The Norma website also includes 150 gr bullets.[1] The data for each should be separated and identified as such—that's the primary problem to be dealt with here. Gene Nygaard (talk) 12:53, 30 December 2007 (UTC)

As for my two cents worth regarding which is primary, I'd first point out that "primary" can have several different meanings in this context. On the Norma pages, which have not only English Swedish but also German language pages, I'd say that the primary units are mass in grains, (the more rounded numbers) for both the bullet and the powder charge. For the rest, speed is given in feet per second and meters per second. Consider both primary; there's no obvious reason to choose one over the other. We can base both the energy in joules and the energy in foot-pounds force on that if we run into discrepancies; it isn't any different than using {{convert}} to convert from one to the other. Doing so and rounding to a reasonable precision might well result in values that might differ from converting the calculated energy value in either unit to the other. Gene Nygaard (talk) 13:10, 30 December 2007 (UTC)

It is probably also worth noting that the mass of the bullet is a design value, whereas speed at the muzzle or anywhere else is strictly a measured value. The design value will have a certain tolerance in actual production, but going by number of "significant digits" and saying that 200 grains only has one significant digit doesn't work. That's one of the main distinctions that needs to be made when considering how to do any conversions. Gene Nygaard (talk) 13:19, 30 December 2007 (UTC)

Well, looks like we need to chose a cartridge/bullet combo to go with. As far as specifications being in metric or U.S. standard it doesn't really matter since we can have both on the page. The argument there would be whether it should be in standard units first or metric. Metric could be chosen since it's a European business, but standard could be chosen also since the nomenclature of the cartridge is in standard (.308) units. Personally, I don't care which comes first, I don't feel it's worth arguing about. We do need to pick a cartridge combo though. Since this is meant primarily as a hunting cartridge I'm thinking we should go with the data for the 11.7 gram Oryx bullet as it's likely more common than the Swift A-Frame one. Muzzle velocity between the two cartridges with 11.7 gram bullets is the same, it's just ballistic coefficient & velocity & energy @ 150 meters that changes. I do wish they would list what firearm they're using for testing (barrel length, etc) but *shrugs*, we have to go with what data we can get. So, what do you guys think? Will the data listed by Norma for the .308 Norma Mag. cartridge utilizing an 11.7 gram Oryx bullet be agreeable for use in the article? Tengu99 (talk) 18:43, 30 December 2007 (UTC)

No reason not to go with all three, is there, since the Norma page has some data on all of them. You might have additional date on one or more of them, of course. Check out some of the other infoboxes, etc., which have several variants, such as .308 Winchester. Gene Nygaard (talk) 12:40, 31 December 2007 (UTC)

Mmm, ok, I'll give it a try then! I'm not a very good editor I'm afraid, but will see what I can do. :) Tengu99 (talk) 21:04, 31 December 2007 (UTC)

I have been bold and removed the unsupported data. I think we should stick with what can be seen on the Norma website. Lightmouse (talk) 11:33, 2 January 2008 (UTC)

Not sure where the ballistics came from, but were well below Norma's data, changed to reflect their data Finnlight (talk) 05:16, 8 September 2008 (UTC)