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Post by reynolds on Nov 2, 2018 21:07:01 GMT
why did bottle necked rifle rds get produced?
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harrybeck
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Post by harrybeck on Nov 2, 2018 21:17:26 GMT
Improved propellant gave higher velocities and provided better terminal ballistics so heavy projectiles weren't needed for the same effects.
The standard method of boosting performance in a platform is to bottleneck to a smaller caliber.
In a nutshell
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Post by bluetrain on Nov 2, 2018 22:22:37 GMT
There were fairly high velocity rounds that were straight-wall cases. But they were long and were not as practical in repeating firearms. A bottleneck cartridge could hold more propellant in a shorter case. Bullets, however, remained relatively heavy until after the turn of the century when it was discovered that a lighter pointed,boattail bullet, among other things, allowed a higher velocity and a longer range with a flatter trajectory. There were a lot of new developments during that relatively short period beginning around 1890. Even so, the .45-70 Government, a straight-wall, rimmed cartridge is nevertheless chambered in repeating rifles.
The same line of reasoning was applied to some handgun cartridges, too, with the .30 Mauser and the .30 Parabellum (or .30 Luger) being introduced around then, too, along with a few others. More recently, the .357 Sig is also a bottleneck cartridge. Ruger produced some pistols chambered in .30 Luger.
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Post by reynolds on Nov 3, 2018 16:12:24 GMT
just skip the rimfire question, eh? :-) I thought so. The advent of jacketed bullets is what made possible the general increase in rifle rd velocity. yes, you can paper patch single shot rifle cartridges, and gas-checked hard cast specialy lubed rifle bullets can maybe handle 2000 fps, but until copper jacketed bullets made the scene, smokeless power and a spitzer shape were of little or no help in attaining the velocities that let us easily reach 200m. Any ballistics chart will show you that the 45-70 drops like a rock and drifts in the wind like a balloon. It's many times easier to hit a man, repeately, at 300m with an AR15, even without a scope than it is with a 50-90 sharps and vernier tang sight.
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Post by reynolds on Nov 3, 2018 16:14:20 GMT
rimfire brass has to be soft enough to allow the indentation from the firing pin to reliably detonate the priming compound. the .22 mag rimfire, in the 60's, had lots of problems with burst cases and misfires. Centerfire priming had to be developed to allow powerful rds to be utilized, with reliable ignition and of course, the soft, removable primer allowed the shottist to reload his fired casings.
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Post by reynolds on Nov 3, 2018 16:24:21 GMT
the first self-contained cartridges were "pinfire" with the detonator being located at the outside edge of the rear of the cartrige. Along about 1860, the .22 short was developed and used in an early S and W pocket revolver, albeit it was SA. The .22lr didn't come along until almost 1890, and was loaded with either black powder or "lesmoke" powder and corrosive priming up into the 1950's, which is why so many nice old bolt action, lever action and single shot .22 rifles either have ruined bores, or they've had new bore liners cunningly installed into their drilled out barrels.
The .56 Spencer was a rimfire, or pinfire, I forget, but as they tried to create more powerful rds, the brass cases burst open at the point of firing pin impact. Stiffer brass was tried, but that caused missfires.
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Post by bluetrain on Nov 3, 2018 17:13:33 GMT
Okay, trivia fans. I have an old cartridge here in front of me; brass case, lead bullet, rimmed (flanged) case with a very wide rim. Caliber about .52", length of case about 1.25 inches. This should give it away: it has no primer but it isn't a rimfire. What is it?
On the subject of bottleneck cartridges, the .38-40 (the case is so marked) is technically a bottleneck cartridge, although one might call it merely a tapered case. Compared with the .44-40 (the case in my possession is marked 44 WCF), one could claim it to be bottlenecked but only by a stretch. In any event, it was originally loaded with a lead bullet. Later these two cartridges were produced in rifle-only loads that were sometimes called "Hi-speed" loads.
Years ago, I had a Lee-Enfield with the 1st half of the barrel, more or less, rather badly pitted but the part near the muzzle was fine and it shot very well, at least as well as I could shoot it.
Ammunition technology went forward in several ways, once the first metallic cartridge was invented. There was smokeless powder in different forms (you should see cordite!), jacketed bullets (also called metal patched), bullets in different shapes, even including one with a step, different kinds of priming and so on. Progress in firearms technology could only advance at the same rate as ammunition technology. But trounds never caught on.
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Post by reynolds on Nov 5, 2018 16:00:03 GMT
sounds like a pinfire rd, for the Spencer rifle, maybe?
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Post by bluetrain on Nov 5, 2018 19:19:05 GMT
I was afraid no one was going to venture a guess. No, it's not a pinfire.
As you know, there were several new breechloading carbines introduced during the Civil War. The carbine that took this particular unusual cartridge was a Maynard. It is unusual in that it is a metallic cartridge with no primer or primer compound within the cartridge. Ignition was by the usual percussion cap on the nipple or with the Maynard priming tape, which looked like and worked like the roll of caps we all used when we were kids in the 1950s. I don't even know if those are still around.
The case has a tiny hose in the base for the ignition. There may have been other cartridges that worked the same way but the looked different. For about twenty years, there were lots of new ideas introduced for firearms and cartridges.
The bullet with a step that I mentioned was from an 8mm Lebel. These unusual cartridges I've mentioned were found in the workshop of my late father-in-law after he passed away about eight years ago. One of the more desirable items that I came home with was a pre-WWI pea green web pistol belt and magazine pouch for a .45 auto.
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