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- .257 Roberts
- .25-06 Remington
- .250-3000 Savage
- .25 caliber
- .243 Winchester
- Caliber
- 7×57mm Mauser
- Roberts
- Winchester Model 54
- 6mm Remington
- Good .257 Roberts loads - 24hourcampfire
- 257 Roberts deer bullet - 24HOURCAMPFIRE
- .257 Roberts on a Remington Short Action? - 24hourcampfire
- Reloading for 257 Roberts - 24HOURCAMPFIRE
- 257 Roberts and elk - 24hourcampfire
- Ruger Hawkeye .257 Roberts - Ruger Forum
- Perfect deer rifle...257 Roberts, or 7x57 - 24hourcampfire
- 6.5x55 vs .257 Roberts - 24HOURCAMPFIRE
- 257 Roberts Accurcacy Issues? - 24HOURCAMPFIRE
- 257 Roberts +P brass vs. regular brass question
.257 Roberts GudangMovies21 Rebahinxxi LK21
The .257 Roberts, also known as .257 Bob, is a medium-powered .25 caliber rifle cartridge. It has been described as the best compromise between the low recoil and flat trajectory of smaller calibers such as the 5 mm (.22 in) and 6 mm (.24 in), and has more energy, but is harder recoiling, similar to larger hunting calibers, such as the 7 mm (.28 in) and 7.62 mm (.30 in).
Nominal bullet diameter of the .257 Roberts is .257 inches. The .257 Roberts uses the same caliber bullets as .250 Savage or the more powerful .25-06 Remington. Barrel rifling diameter, from which calibers derive their designations, is 0.250 in or 6.35 mm.
History
Many cartridge designers in the 1920s were creating various 6.35 mm (.25 in) caliber cartridges. Due to the availability of inexpensive Mauser actions, the 7×57mm Mauser case was a common choice, having near ideal volume capacity for the "quarter-bore" (0.25 in; 6.35 mm) using powders available at that time. Ned Roberts is usually credited with being the designer for this cartridge. Eventually, in 1934, Remington Arms chose to introduce their own commercial version of such a cartridge, and although it was not the exact dimensions of the wildcat made by Roberts, they called it the ".257 Roberts".
From its introduction until the appearance of 6 mm cartridges such as .243 Winchester and 6mm Remington, it was a very popular general purpose cartridge. Today, although surpassed in popularity by other cartridges, it lives on with bolt-action rifles being available from some major manufacturers.
Conversion of war-souvenir Japanese Arisaka rifles
Japanese Type 38 Arisaka rifles brought to the United States as wartime souvenirs were sometimes converted by rechambering to utilize more readily available .257 Roberts cartridge cases because commercially produced 6.5×50mm Arisaka cartridges were scarce prior to distribution by Norma Projektilfabrik A/S. The neck of the Roberts case would be slightly enlarged to accept handloaded 6.5 mm bullets. The modified Roberts cases are sometimes known as "6.5×.257 Roberts", although the case headstamp may still indicate .257 Roberts. Neither unmodified .257 Roberts ammunition nor the original 6.5×50mm Arisaka ammunition are suitable for firing in rechambered Arisaka rifles.
Performance
With light bullets, the .257 produces little recoil, and has a flat trajectory suitable for varmint hunting. With heavier bullets it produces more recoil, but is capable of taking all but the largest North American game animals. The original factory load for this is very similar to the .250-3000 Savage.
Improved cartridges
Remington introduced the commercial version of this popular wildcat as a low-pressure round. At the time there were many older actions available of questionable strength. With a modern action and handloading, this cartridge is capable of markedly improved performance.
One of the common improvements is called the ".257 Roberts +P" which has a SAAMI maximum pressure limit of 58,000 psi (400 MPa) compared to the 54,000 psi (370 MPa) listed for the standard .257 Roberts. It is also the only rifle cartridge with an official "+P" designation.
P.O. Ackley said that the .257 Roberts Ackley Improved was probably the most useful all-around cartridge. Making an Ackley Improved cartridge usually meant modifying the chamber to have a steeper shoulder and blown-out sides to provide greater powder capacity while still allowing factory ammunition to be fired safely.
Comparison
Data below shows sample muzzle velocities and muzzle energies for a 61 cm (24 in) test barrel, except .250-3000 Savage, which is for a 56 cm (22 in) test barrel and .257 Weatherby Magnum, which is for a 66 cm (26 in) test barrel.
See also
6 mm caliber
Delta L problem
List of rifle cartridges
Table of handgun and rifle cartridges
References
External links
.257 Roberts at Reloaders Nest
.257 Roberts (257 Roberts +P) at The Reload Bench
Kata Kunci Pencarian:
257 Roberts — Nosler
257 Roberts — Northwest Magnum
Survival Ammunition: .257 Roberts - RedTea News
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257-Roberts | The Ballistic Assistant
257 roberts
Daftar Isi
Good .257 Roberts loads - 24hourcampfire
Rifles chambered for the 257 Roberts can vary a great deal. I had a 1976 vintage Ruger 77 tang safety Roberts with a sloppy chamber and a very long throat. It would take 43 grains of RL-15 to get a 100 grain bullet to 3,000 fps. My current Roberts is a Savage Axis with an E.R. Shaw barrel and a short throat.
257 Roberts deer bullet - 24HOURCAMPFIRE
Oct 11, 2018 · According to my hunting notes, my wife and I have used the following bullets from various .257 Roberts rifles (including one Ackley Improved) on big game, mostly deer but also plenty of antelope, quite a few feral pigs and goats, and one cow elk: Barnes 100 XLC, TSX, and TTSX Berger 115 Hunting VLD Hornady 100 Spire Point and 117 boattail Spire ...
.257 Roberts on a Remington Short Action? - 24hourcampfire
Nov 16, 2012 · Hornady 117 grain +P .257 Roberts factory ammo (OAL of 2.785" as measured) fits the magazine perfectly and shoots under 1 MOA while fire forming. There is little need for anything heavier or longer for most game hunting. This is the third iteration of a SA M-700 in .257 Roberts Ackley Improved I have owned, all worked perfectly.
Reloading for 257 Roberts - 24HOURCAMPFIRE
May 4, 2017 · The slower powders work better with heavy bullets for me in the 257 Roberts.. 48gr of RL26 with WLRM primers and win cases gets about 3120fps for 5 shots using 115gr Nosler partitions. RL23 with 48.2gr with 110gr Accubonds CCI250 mag primers win cases 3157 fps. All in a model 70 Winchester. MRP,and RL22 gave similar performance.
257 Roberts and elk - 24hourcampfire
May 15, 2011 · One of the biggest elk I have ever seen (approaching 400) was killed with a .257 Roberts and I believe a Partition. I helped with the skinning and pulled several 30 cal cup-and-core bullets out of his shoulders. They were all scarred over from years past, and the shoulder bones stopped those bullets.
Ruger Hawkeye .257 Roberts - Ruger Forum
Jan 5, 2019 · I shot a friend of mines .257 Roberts M77 UL. As I recall I shot Hornady 117 grainers, which he said was the most accurate load. It shot mildly for the weight of the rifle, as you would expect out of a Roberts. Accuracy wise it was …
Perfect deer rifle...257 Roberts, or 7x57 - 24hourcampfire
Nov 21, 2011 · I am however torn between a .257 Roberts and a 7x57. And no I don't want a 7-08. My gf shoots one and while it's probably about as perfect of a whitetail round out there I'm just drawn to the classics. So if you were rifle shopping today would you 1) ruger m77 .257 Roberts 2) ruger m77 7x57.
6.5x55 vs .257 Roberts - 24HOURCAMPFIRE
Jan 13, 2020 · I bought a bag of 100 257 cases 5 years ago, still using them, still reloading them, shooting a Kimber select classic 257 roberts, bullets of course are easy to find, now I mostly shoot 117 grain Hornady bullets over H4350.
257 Roberts Accurcacy Issues? - 24HOURCAMPFIRE
Feb 13, 2013 · What is the twist of your friend's 257 Roberts? If it is 1-12, then keep the bullet weight down to 87 grains. 100 grain flatbase MAY be ok. If the twist is 1-10, then try 100 grainers. I had 1 257 roberts. It was on a WWII wartime M98 Mauser with an unknown barrel. Nice sporter, but not high end. It DID have double set triggers(a nice touch).
257 Roberts +P brass vs. regular brass question
Apr 13, 2020 · And in what way? Too much pressure? My load recipe has been the 90 gr. Barnes X bullet/46.5 grains IMR 4350/Remington 9-1/2 for a Winchester Model 70 FWT. My last batch of brass had been loaded so many times, the necks started cracking after every shot. I bought some new 257 Roberts brass (Winchester) and noticed the headstamp said +P.