257 roberts reloading data

Oct 31, 2021 ... The other factory loads with 115gr and 117gr bullets, listed as +P, are in the 2950 fps neighborhood. I don't know enough about this cartridge ...

.257 Diameter Bullets 75 gr. HP 87 gr. SPT 90 gr. HPBT 100 gr. SPT 100 gr. SBT 117 gr. SBT 117 gr. SPT 120 gr. HPBT.264 Diameter Bullets 85 gr. HP 100 gr. HP 120 gr. SPT The current SAAMI spec for the .257 Roberts Maximum Average Pressure (MAP) is 54,000 psi. Winchester introduced a +P version with a MAP of 58,000 psi in the mid-1980s. That’s still less than the typical 60,000 to 65,000 psi of comparable modern rifle cartridges. The .257 Roberts was pretty popular for a few years before and after World …Warning! Notes: .257 Roberts, Ruger M-77 long action 24-inch barrel; Remington cases, 186 grains; CCI No. 200 primers; Oehler M-31 Chronotach, Oehler M-50 photoelectric screens; velocity at 15 feet converted to MV; temperature 70 degrees; this rifle had a rather loose chamber and would handle more powder than most rifles with every bullet ...Load Data for .257 Roberts . Bullet: 80 gr TTSX BT (Barnes) Diameter: 0.257" Powder: H380 (Hodgdon) Starting Powder: 41.0 gr. Max Powder: 45.0 gr . .257 Roberts Improved Data reloading data with 40 loads. Using bullets from Hornady, Sierra HP, Rem. Power Lokt, Sierra, Hornady Spire Point, Hornady Round Nose, Barnes. We place limited powder inventory for sale on a regular basis on our website. When we are sold out, we are sold out. We do not take backorders and our Tech Services team cannot take orders via email or phone. The max order quantity of any powder SKU is 5 and we will only accept one order, per customer, per calendar month with a maximum weight ....257 Roberts (Hodgdon CFE 223 Data) reloading data with 6 loads. Using bullets from Hornady SP, Hornady HP, Barnes TTSX BT. ... .257 Roberts (Hodgdon CFE 223 Data) Warning! Notes: case: Remington; barrel length: 24"; twist: 1:10"; trim length: 2.223"; primer: Remington 9 1/2; bullet diam.: .257"; NEVER EXCEED MAXIMUM LOADS Be Alert: …

Reloder 16. Select A Caliber or Gauge Below To View Recipes. 243 Win. 25-06 Rem. 257 Roberts. 260 Rem. 270 Win. 270 Win. Short Magnum..257 Roberts (Cast Bullet Loads) reloading data with 9 loads. Using bullets from Lyman 257463, Lyman 257464, Lyman 257235. Powders include Alliant, IMR1. Never begin loading with the maximum powder charge shown in these reloading data tables, regardless of your experience. 2. Never exceed maximum loads because excessive chamber pressure will result. 3. Discontinue firing at the first sign of excessive pressure or upon noticing a change in the. report of the firearm.Load Data for .257 Roberts . Bullet: 80 gr TTSX BT (Barnes) Diameter: 0.257" Powder: H380 (Hodgdon) Starting Powder: 41.0 gr. Max Powder: 45.0 gr . Remarks: COAL: 2.750 inches; maximum load. .257 Roberts (using Sierra bullets) reloading data with 391 loads. Using bullets from Sierra HP, Sierra SPT, Sierra SPT , Sierra HPBT, Sierra SPT, SBT or HPBT MatchKing, Sierra SPT or SBT, Sierra SPT or SBT , Sierra SPT or SBT . Powders include IMR, Hodgdon, Accurate, Vihtavuori, Ramshot, Alliant.

The .257 Roberts is a low recoiling, mild powered cartridge. In a short action, it has the potential for a suitable youth rifle but without care towards optimizing hand loads, can lack the power with many 117 to 120 grain loads to be ….257" 25 Spitzer SP Hot-Cor® 25 HP 25 Spitzer BTSP Weight (grains) 100 Ballistic Coefficient 0.334 0.263 0.393 Sectional Density 0.1260.216 COAL Tested 2.770"2.760" Speer Part No. 1405 1407 1408 Propellant Case Primer Weight (grains) Muzzle Velocity (feet/sec) Weight (grains) Winchester 760 Winchester CCI 250 41.0 2804 45.0kleanbore 1. Oct 31, 2020. #1. Any long time shooters of the 257 Roberts, a question for you. What powders do you prefer for the heavier bullets, say 90gr-120gr I have IMR 4350, 4064, 3031, Varget , Reloader 15 and others. I know, what shoots good in your rifle may not in mine. Looking for a consensus on where to start.IMR-7828. Subscribe. 2,608. Remarks: .257 Roberts Carbine reloading data with 33 loads. Using bullets from Sierra jacketed hollowpoint, Hornady Spire Point, Sierra hollowpoint boat-tail, Nosler Ballistic Tip, Nosler Partition, Sierra spitzer boat-tail, Speer spitzer boat-tail. Powders include Hodgdon, IMR, Alliant, Accurate.

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.257 Roberts (Barnes Reloading Manual #4) reloading data with 40 loads. Using bullets from Barnes TTSX BT, Barnes Banded Solid Spitzer, Barnes TSX BT, Barnes TSX FB. Powders include IMR, Ramshot, Hodgdon, Vihtavuori, Accurate, Alliant ... .257 Roberts (Barnes Reloading Manual #4) Warning! Notes: case: R-P (except where otherwise …Load Data for .257 Roberts. Bullet: 115 gr PART (NOS) Diameter: 0.257" Powder: StaBALL 6.5 (Winchester) Starting Powder: 38.5 gr. Max Powder: 43.0 gr. Primer: REM 9½. Case: REM. Trim Length: 2.223" Cartridge Overall Length: 2.890" Starting Velocity: 2,595. Starting Pressure: 38,800. Max Velocity: 2,831. Max Pressure: 46,000 CUP.The .257 Roberts, also known as .257 Bob, [2] 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 ...If you’ve ever had a debit card marked “nonreloadable,” you may wonder what that means. It simply means once the balance has been depleted, you can’t put more money on it. However,...Be Alert: Publisher cannot be responsible for errors in published load data. Wt. .257 Roberts in a Rem 700 Classic reloading data with 31 loads. Using bullets from Speer spitzer, Hornady hollow-point, Sierra boat-tail hollow-point, Speer spitzer boat-tail, Hornady round-nose, Nosler partition spitzer. Powders include Winchester, IMR, Hodgdon ...

Today we're choosing a load and we're going to select our bullet, powder, brass, and primer. And we're not just choosing a load for accuracy but a lot that w...Load Data for .257 Roberts . Bullet: 115 gr PART (NOS) Diameter: 0.257" Powder: Hybrid 100V (Hodgdon) Starting Powder: 42.0 gr. Max Powder: 46.0 gr .Wt. .257 Roberts reloading data with 8 loads. Using bullets from Sierra jacketed hollowpoint, Hornady jacketed hollowpoint, Speer jacketed hollowpoint, Nosler Solid Base, Nosler Partition, Sierra spitzer boat-tail, Hornady hollowpoint. Powders include IMR, Norma, Hodgdon, Winchester.The 257 Roberts is built on the 7x57 case. All different. The loading information on the 117gr and 120gr is used interchangeably on the 25-06, so probably so on the 25 Souper also. ... In Speer wildcat manual # 4 published 1959 they list loading data for the 257 Improved,25 Neidner (25-06) and 25 Souper. ... You have to remember that P.O. …257 Roberts Load Data Using Hornady reloading data with the 257 Roberts bullets creates a great round that is popular with hunters who like its low recoil rates. The .257 Roberts dates way back to around the 1920's but many still use it to this day. Be Alert: Publisher cannot be responsible for errors in published load data.Reloading data for 257 Roberts. Bullet: Hornady SP 87 gr: Bullet weight: 5.6 g / 87 gr: B.C: 0.322: C.O.L: 70.0 mm / 2.756 # 2530: Gunpowder Charge Weight Velocity m/s Velocity fps; Norma 204: ... An introduction to reloading - Part 8 An introduction to reloading- Part 3 Calibers Show all Calibers ...257 is offered in a number of factory loads with 117-120 grain bullets. The 120 grain spitzer bullet as factory loaded by Federal claims a muzzle velocity (MV) ...Wt. .257 Roberts (Using Nosler Bullets) reloading data with 150 loads. Using bullets from Nosler BT, or CT Ballistic Silvertip, Nosler BT, Partition Spitzer or E-Tip, Nosler Accubond, Nosler Solid Base Ballistic Tip (blue), Nosler, Nosler Partition Spitzer. Powders include Alliant, Accurate, IMR, Hodgdon, Vihtavuori, Ramshot, Winchester.Sep 24, 2022 ... These recoil figures can be adjusted with heavier or lighter bullets, of course, but when using the most common factory loads, the .257 Roberts ...

2,694. Remarks: .257 Roberts Ackley Improved (Using Nosler Bullets) reloading data with 135 loads. Using bullets from Nosler Ballistic Tip or CT Ballistic Silvertip , Nosler Ballistic Tip or CT Ballistic Silvertip, Nosler Ballistic Tip, E-Tip or Partition Spitzer, Nosler Accubond, Nosler Ballistic Tip, CT Ballistic Silvertip or Pa, Nosler ...

.257 Diameter Bullets 75 gr. HP 87 gr. SPT 90 gr. HPBT 100 gr. SPT 100 gr. SBT 117 gr. SBT 117 gr. SPT 120 gr. HPBT.264 Diameter Bullets 85 gr. HP 100 gr. HP 120 gr. SPT Reloading . John Barnsness , .257 Bore article. ... 250/3000 .257 roberts 25,06 and the .257 weatherby magnum. I have exchanged PMs with John , on the Roberts and the wetherby mag, on a few ocaisions. The data that intrests me in particular, is in The Roberts. (duh , I do call myself TJ Roberts).Jun 21, 2020 ... Best loads for 257 roberts with 117gr hornady sst h380 powder nosler +p brass and cci LR 200 primers. 10 years ago I made some loads that shot ...The Hornady Handbook and Nosler Reloading Guide show maximum reloads for the .257 Improved (either version) achieving muzzle velocities (MV) of about 3600 fps with a 75 …Oct 15, 2022 ... ... data, 2 or 3 online ballistic calculators for ballistic data. Do not modify any cartridge or firearm beyond what the manufacturer recommends ....257 Roberts (using Sierra bullets) reloading data with 391 loads. Using bullets from Sierra HP, Sierra SPT, Sierra SPT , Sierra HPBT, Sierra SPT, SBT or HPBT MatchKing, Sierra …Revised 12/2009 Indicates most accurate load. Bullet Weight:80 grCase Trim Length:2.223"S.D.0.173. Bullet Style:TTSX BTPrimer:Fed 210B.C.0.316. …

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For that reason, it is normally not recommended. This is not an issue with thinner, American-made 6mm Remington and .257 Roberts brass. Hornady’s Handbook of Cartridge Reloading, Tenth Edition, lists trim-to specifications as 2.222 inches and maximum overall case length as 2.232 inches. Unfortunately, it also lists only three older IMR ...Load Data for .257 Roberts . Bullet: 80 gr TTSX BT (Barnes) Diameter: 0.257" Powder: H380 (Hodgdon) Starting Powder: 41.0 gr. Max Powder: 45.0 gr .Notes from the Lab: .257 Roberts (using Sierra bullets) N.H. “Ned” Roberts developed the .257 Roberts during the 1920s by necking the 7mm Mauser (aka 7x57) case to accept .257-inch bullets and by changing the shoulder angle from 20 ... data is loaded to +P pressures and should only be used in modern actions intended for the increased pressures.Vihtavuori offers reloading data for nearly a hundred different handgun and rifle calibers and for shotgun loads, with numerous bullet options for all kinds of shooting disciplines and needs. Please note that the data we offer on our website, in our newest Reloading Guide and in the Vihtavuori Reload App is all the official and safe load data ... .257 Roberts Ackley Improved Data reloading data with 4 loads. Using bullets from Hornady V-Max, Barnes XLC, Nosler Ballistic Tip, Nosler Partition. Powders include Ramshot, Hodgdon, Accurate, Alliant 2,744. Remarks: 0.93 inch. .257 Roberts, 22-Inch Barrel reloading data with 14 loads. Using bullets from Hornady hollowpoint, Sierra hollowpoint, Hornady pointed softnose, Sierra pointed softnose, Nosler Partition, Nosler Ballistic Tip, Hornady spitzer boat-tail, Sierra spitzer boat-tail, Remington roundnose, Hornady roundnose, Speer spitzer ...For that reason, it is normally not recommended. This is not an issue with thinner, American-made 6mm Remington and .257 Roberts brass. Hornady’s Handbook of Cartridge Reloading, Tenth Edition, lists trim-to specifications as 2.222 inches and maximum overall case length as 2.232 inches. Unfortunately, it also lists only three older IMR ...Plus, you can save favorites, add notes and more. Reloading data is available as low as 99¢ per cartridge or as a subscription for $19.99. Below you’ll find some basic data for each cartridge to help get you started. Basic Load Data. Hornady Manufacturing Company develops and publishes reloading data for the Handbook of Cartridge Reloading. Load Data for .257 Roberts . Bullet: 120 gr HPBT (Sierra) Diameter: 0.257" Powder: IMR 4350 (Improved Military Rifle) Starting Powder: Max Powder: 41.5 gr . Primer ... The .257 Roberts was the premier combination varmint/deer cartridge until the .243 Winchester and .244 Remington were introduced in 1955. These cartridges were highly touted by Warren Page, the Shooting Editor at Field & Stream magazine, and appeared to be ballistically superior to the .257 Roberts.257 Roberts Ackley Improved Load Data. 85 Grain. 100 Grain. 110 Grain. 115 Grain. 120 Grain. Explore the world of Nosler, renowned for crafting the finest bullets, ammunition, rifles, and brass. Discover our extensive lineup, including Partition, AccuBond, E-Tip, Ballistic Tip, Custom Competition, and more. Experience superior quality and ...Load data for 39 loads in caliber .257 Roberts with .257 | 100gr | Sierra SBT GameKing bullet including underlying parameters such as bullet length, ... ….

I have a Howa 1500 that has been rebarreled by E.R.Shaw to .257 Roberts with a 24" magnum contour barrel with 1:10 twist. It is topped with a Weaver V10 scope in Leupold mounts. I'm planning to make this my main deer rifle and hopefully print tiny groups with it too. I'm planning to use heavier bullets of 110-120 grains at modest velocity, 2600 ...This data was developed to the 257 Roberts +P pressure level of 58,000 psi, and should only be used in modern rearms and +P cases designed for these pressures.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.Joined: Sep 2007. Posts: 11. I'm planning to start reloading a Ruger M77 in 257 Roberts with H4350 powder and Speer 120 bullets which I currently have on hand. I will be using Winchester +P brass. The Speer manual does not have a load listed using H4350. I have seen suggested maximum loads in articles ranging from 42 grains to 47 grains …*To fire-form brass, use the faster-burning powders and loads from standard .257 Roberts data. *To properly chamber a rifle for .257 Ackley Improved cartridges, a gunsmith must set the original barrel back about 0.004”. The chamber distance from the bolt face to the junction of shoulder and neck is shorter in Ackley Improved rifles than in ...Today we're choosing a load and we're going to select our bullet, powder, brass, and primer. And we're not just choosing a load for accuracy but a lot that w...Revised 12/2009 Indicates most accurate load. Bullet Weight:80 grCase Trim Length:2.223"S.D.0.173. Bullet Style:TTSX BTPrimer:Fed 210B.C.0.316. … Reloder 16. Select A Caliber or Gauge Below To View Recipes. 243 Win. 25-06 Rem. 257 Roberts. 260 Rem. 270 Win. 270 Win. Short Magnum. Tucson, Az. Tucson, Az. I went to Alliant's site and they don't mention RL-17 with the 257 Roberts. I have loaded it in a 6mm Rem, 284 and 7 Rem Mag. Charge weights are similar to using 4350. I'd try to call Alliant and ask them. For what it worth Alliant lists a 100 gr bullet in the 6mm Rem with a max load of 44 gr of RL-17. 257 roberts reloading data, .257 Roberts Improved Data reloading data with 40 loads. Using bullets from Hornady, Sierra HP, Rem. Power Lokt, Sierra, Hornady Spire Point, Hornady Round Nose, Barnes., The .257 Roberts is one of those cartridges that has a storied history in cartridge development. Noted gun and cartridge experimenter – Dr. Franklin Mann – was indeed a very important part of the .25-caliber concept. Ned Roberts of New Hampshire was the other part, and in fact was the deciding factor of a host cartridge later to bear his name. , The 257 Roberts is built on the 7x57 case. All different. The loading information on the 117gr and 120gr is used interchangeably on the 25-06, so probably so on the 25 Souper also. ... In Speer wildcat manual # 4 published 1959 they list loading data for the 257 Improved,25 Neidner (25-06) and 25 Souper. ... You have to remember that P.O. …, Refer to the current SPEER® Reloading Manual for handloading instructions. Be thoroughly familiar with those instructions before using these loads. As Vista Outdoor Operations LLC has no control over individual handloading practices or the condition of firearms in which ... 257 Roberts +P 3290 3386 3381 3367 3295 3226 3187 3184 3170 3163 3153 ..., Revised 12/2009 Indicates most accurate load. Bullet Weight:80 grCase Trim Length:2.223"S.D.0.173. Bullet Style:TTSX BTPrimer:Fed 210B.C.0.316. COAL:2.830"Barrel Length:24". Case:W-WTwist Rate:1:10". Charge Velocity Charge Velocity Load Powder (grains) (fps) (grains) (fps) Density (%) H380 43.0 3108 47.0 3415 89 H414 43.5 3109 47.5 3399 87 RL ..., Remarks: COAL (inches): 3.020; 3-shot 100-yard group (inches): .77. .257 Roberts Ackley Improved (Load Development) reloading data with 45 loads. Using bullets from Nosler Ballistic Tip Varmint, Hornady GMX, Hornady ELD-X, Nosler Ballistic Tip Hunting, Berger VLD Hunting. Powders include Hodgdon, Alliant, Ramshot, IMR, Accurate, Vihtavuori ..., Load Data for .257 Roberts. Bullet: 117 gr SBT (Sierra) Diameter: 0.257" Powder: 2520 (Accurate) Starting Powder: 32.9 gr. Max Powder: 36.5 gr. Primer: FED 210. Case: REM. …, .257 Roberts (Accurate Rifle Data) reloading data with 19 loads. Using bullets from Sierra HP, Sierra HPBT, Nosler BT, Sierra SBT. Powders include Accurate ... .257 Roberts (Accurate Rifle Data) Warning! Notes: gun: DOUGLAS; barrel length: 24 inches; primer: CCI 200; case: ..., Notes: Loads fired from a 24-inch barreled Montana Rifle Company Woodland .257 Ackley Improved with a Leupold 3.5-10x, set on 10x. All loads shot with Winchester Large Rifle primers. All cases were fireformed from .257 Roberts brass, and all groups were fired at 100 yards, except where noted. (Handloader Issue #266 - June, 2010), Stan's .257 Roberts is a Winchester Model 70 Featherweight. The .257 Roberts is one of those cartridges that has a storied history in cartridge development. Noted gun and cartridge experimenter – Dr. Franklin Mann – was indeed a very important part of the .25-caliber concept. Ned Roberts of New Hampshire was the other part, and in fact was ... , .257 Roberts +P Handload Data (50,000 CUP) reloading data with 19 loads. Using bullets from Hornady V-Max, Speer flat softpoint, Hornady Spire Point, Nosler Ballistic Tip, Nosler Partition, Speer spitzer boat-tail. Powders include Hodgdon, Accurate, Alliant, Vihtavuori, Date: Feb 11 2014. N.H. "Ned" Roberts developed the .257 Roberts cartridge during the 1920s by necking the 7mm Mauser case to accept .257-inch bullets, and by changing the shoulder angle from 20 to 15 degrees. Roberts was a well-known experimenter and gun writer, and his cartridge became a popular wildcat among custom rifle builders and hunters., .257 Roberts (Hodgdon Data - Winchester Powder) reloading data with 14 loads. Using bullets from Hornady SP, Hornady HP, Barnes TTSX BT, Sierra HPBT, Speer SPBT, Nosler Part. ... twist: 1:10"; trim length: 2.223"; primer: Remington 9 1/2; bullet diam.: .257". NEVER EXCEED MAXIMUM LOADS: Be Alert: Publisher cannot be responsible for errors in ..., The .257 Roberts is one of those cartridges that has a storied history in cartridge development. Noted gun and cartridge experimenter – Dr. Franklin Mann – was indeed a very important part of the .25-caliber concept. Ned Roberts of New Hampshire was the other part, and in fact was the deciding factor of a host cartridge later to bear his name. , Notes: Test rifles: prewar Model 70 (24-inch barrel) and 1981 Model 70 Featherweight (22-inch barrel). (Handloader Issue 94) Be Alert: Publisher cannot be responsible for errors in published load data. Wt. .257 Roberts (Pet Loads Update) reloading data with 67 loads. Using bullets from Sierra HP, Hornady HP, Speer Sp, Sierra Sp, Hornady SP ..., 257 ROBERTS · 25-06 REMINGTON · 257 WEATHERBY MAGNUM · 6,5 JAPANESE ARISAKA · 6,5 CARCANO · 6,5x54 M-S · 260 REMINGTON · 6,5x55 SWE..., 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., Well, I'm about three weeks into reloading for the .257 Roberts +P. So far I have three good loads worked up and have loaded but not test-fired another batch. The results so far: Common components. Win brass, CCI 250 primer. 75g Hornady VMAX. COL 2.8025". 42.0g Varget. 3187fps, 7.0fps STD, 16fps E.S., It is considered to be about the maximum capacity for the .25 bore and still produce satisfactory performance and good barrel life. The Improved .257 can be readily recommended. (Handbook for Shooters & Reloaders/Vol. 1 - P.O. Ackley, 1962) NOTE: USE THIS DATA WITH EXTREME CAUTION. Be Alert: Publisher cannot be responsible for errors in ..., The .257 Roberts A.I. holds around 56.6 to 58.5 grains of water beneath a seated bullet, to the .257 Roberts 51.4 to 53.6 grains, all other factors remaining equal. Hornady’s 90-grain GMX paired best with. 43.5 grains of IMR-4064 at a velocity. of 3,302 fps. That three-shot, 100-yard group. measured .58-inch., Well, I'm about three weeks into reloading for the .257 Roberts +P. So far I have three good loads worked up and have loaded but not test-fired another batch. The results so far: Common components. Win brass, CCI 250 primer. 75g Hornady VMAX. COL 2.8025". 42.0g Varget. 3187fps, 7.0fps STD, 16fps E.S., 56 posts · Joined 2003. #4 · Jul 24, 2008. My .257 AI built on a pre-64 Win M70 action and Douglas Premium barrel likes the following load: Winchester brass. CCI Large Rifle Primers. 100 gr. Nosler Partitions. 50 grs. IMR 4350. Load chronographs at 3200 fps and shoots 5/8" three shot groups at 100 yards., Load Data for .257 ROBERTS ACKLEY IMPROVED . Bullet: 75 gr HP (Sierra) Diameter: 0.257" Powder: 4350 (Accurate) Starting Powder: 49.5 gr. Max Powder: 55.0 gr ., .257 Roberts (Hodgdon Data - Winchester Powder) reloading data with 14 loads. Using bullets from Hornady SP, Hornady HP, Barnes TTSX BT, Sierra HPBT, Speer SPBT, Nosler Part., 257 Roberts Ackley Improved Load Data. 85 Grain. 100 Grain. 110 Grain. 115 Grain. 120 Grain. Explore the world of Nosler, renowned for crafting the finest bullets, ammunition, rifles, and brass. Discover our extensive lineup, including Partition, AccuBond, E-Tip, Ballistic Tip, Custom Competition, and more. Experience superior quality and ..., 257 ROBERTS · 25-06 REMINGTON · 257 WEATHERBY MAGNUM · 6,5 JAPANESE ARISAKA · 6,5 CARCANO · 6,5x54 M-S · 260 REMINGTON · 6,5x55 SWE..., Load Data for .257 Roberts . Bullet: 100 gr SPBT (Speer) Diameter: 0.257" Powder: IMR 4895 (Improved Military Rifle) Starting Powder: 39.0 gr. Max Powder: 41.0 gr ., .257 Roberts (Cast Bullet Loads) reloading data with 9 loads. Using bullets from Lyman 257463, Lyman 257464, Lyman 257235. Powders include Alliant, IMR, .257 Roberts (Winchester Rifle Data) reloading data with 5 loads. Using bullets from Hornady SP, Hornady Hollow Point, Sierra Hollow Point Boat Tail, Speer Soft Point Boat Tail, Nosler Part. Powders include Winchester, May 19, 2011 ... Again, seated one caliber deep, for an OAL of 2.976", QuickLoad suggests a compressed charge of 56 grains IMR7828, generating just under 47,000 ..., The .257 Roberts was the premier combination varmint/deer cartridge until the .243 Winchester and .244 Remington were introduced in 1955. These cartridges were highly touted by Warren Page, the Shooting Editor at Field & Stream magazine, and appeared to be ballistically superior to the .257 Roberts., Reloder 16. Select A Caliber or Gauge Below To View Recipes. 243 Win. 25-06 Rem. 257 Roberts. 260 Rem. 270 Win. 270 Win. Short Magnum., For a performance comparison, let’s put current .257 Roberts +P handloads next to its more modern challenger, the .25-06 Remington (1969). Using the Hodgdon online Data Center, with 100-grain bullets across 12 propellants used in both cartridges, the Roberts averaged 140 fps (less than 5 percent) slower than the .25-06.