Reliable 38-55 reloading data can be found in legacy manuals like the Lyman 47th Reloading Handbook, directly from bullet manufacturers like Barnes, and through Hodgdon’s online data center. Published data typically includes the specific bullet, bullet weight, powder type, starting powder charge, maximum powder charge, muzzle velocity, and the barrel length of the test firearm. Available data heavily favors 250 grain to 255 grain projectiles, ranging from cast lead flat nose bullets to jacketed soft points.Reputable powder manufacturers provide load recipes using medium to fast burning rifle powders like IMR 3031, Reloder 7, and H4895, as well as pistol powders like Unique for low velocity cowboy action shooting. Results vary drastically by bullet diameter, powder, brass case length, primer, and whether the firearm is an antique black powder action or a modern steel replica.
38 55 Reloading Data
| Bullet | Bullet Weight | Powder | Published Starting Load | Published Maximum Load | Published Velocity | Barrel Length / Firearm | Source |
| Barnes Original JFP | 255 grain | Reloder 7 | 23.0 gr | 27.0 gr | 1486 fps to 1745 fps | 26 inch Barrel | Barnes Bullets |
| Barnes Original JFP | 255 grain | IMR 3031 | 28.0 gr | 32.0 gr | 1420 fps to 1623 fps | 26 inch Barrel | Barnes Bullets |
| Remington JFP | 255 grain | IMR 3031 | 31.0 gr | 35.0 gr | 1271 fps to 1805 fps | 26 inch Barrel | Lyman 47th Handbook |
| Lead Flat Nose Cast | 250 grain | Hodgdon H4895 | 21.0 gr | 26.0 gr | 1197 fps to 1600 fps | 24 inch Barrel | Lee Precision / Hodgdon |
| Barnes Original JFP | 255 grain | Hodgdon H322 | Not Specified | 31.0 gr | 1650 fps | Universal Receiver | Independent Testing |
| Hard Cast Gas Check | 265 grain | IMR 4198 | 18.0 gr | 21.0 gr | 1241 fps to 1464 fps | Winchester 1894 | Independent Testing |
Understanding The 38 55 Reloading Data
When interpreting any 38-55 load data chart, it is critical to understand the nuances of this historical cartridge to ensure safe operation.
- Starting load: The minimum tested powder charge recommended by the publisher to safely cycle the bullet out of the barrel and prevent squibs.
- Maximum published load: The absolute ceiling for a specific powder charge tested by the manufacturer. Exceeding this is incredibly dangerous in vintage firearms.
- Velocity: Measured in feet per second (fps), indicating how fast the projectile travels when leaving the muzzle.
- Pressure: The internal chamber pressure generated upon firing. The SAAMI standard maximum average pressure for the 38-55 Winchester is 30,000 CUP (Copper Units of Pressure).
- Bullet weight: The mass of the projectile measured in grains.
- Powder: The specific chemical propellant used.
- Barrel length: The length of the barrel used during testing, which directly impacts velocity.
- Firearm used for testing: Specifies whether the test was conducted with a universal receiver or a specific lever action rifle.
- Cartridge overall length (COAL): The total length of the loaded round. Barnes tests their 255 grain jacketed flat point with a COAL of 2.470 inches.
Different published sources may produce different results because slight variations in brass case capacity, primer ignition temperature, and atmospheric conditions directly affect the burn rate. Most importantly, the 38-55 has massive variations in original factory bore diameters, meaning pressure curves change depending on how tightly a specific bullet seals in a specific barrel.
38 55 Bullet Weight Reloading Data
The 38-55 Winchester was originally a black powder target cartridge and later adapted for lever action hunting rifles, leading to a specific range of heavy flat nosed bullet weights.
- 200 grain and 220 grain: These lighter bullets are produced by companies like Sierra and Hornady. They are primarily jacketed soft points intended to achieve slightly higher velocities (around 1,600 fps) and flatter trajectories for deer hunting.
- 240 grain and 250 grain: The traditional target weights for cast lead bullets. Manufacturers like Lyman provide extensive data for 250 grain cast bullets, which are highly popular in Cowboy Action Shooting and vintage rifle matches.
- 255 grain: The absolute standard weight for the 38-55 Winchester. Both Barnes and Winchester factory ammunition rely on the 255 grain jacketed flat point (JFP). Extensive published data exists for this weight across nearly all powder brands.
- 260 grain and 265 grain: Heavy cast bullets usually equipped with gas checks to prevent lead fouling at higher velocities. These are favored by reloaders looking for maximum penetration on large game like black bear.
When selecting a bullet, reloaders must determine their exact bore diameter. Vintage 38-55 rifles can have groove diameters ranging anywhere from .375 inches up to .382 inches. Firing a .380 inch cast bullet through a tight .375 inch bore will dramatically increase chamber pressure.
38 55 Powder Reloading Data
| Powder | Bullet | Bullet Weight | Published Starting Load | Published Maximum Load | Published Velocity | Source |
| Reloder 7 | Barnes JFP | 255 grain | 23.0 gr | 27.0 gr | 1486 fps to 1745 fps | Barnes Bullets |
| IMR 3031 | Barnes JFP | 255 grain | 28.0 gr | 32.0 gr | 1420 fps to 1623 fps | Barnes Bullets |
| IMR 3031 | Remington JFP | 255 grain | 31.0 gr | 35.0 gr | 1271 fps to 1805 fps | Lyman 47th Handbook |
| Hodgdon H4895 | Lead Flat Nose | 250 grain | 21.0 gr | 26.0 gr | 1197 fps to 1600 fps | Lee Precision / Hodgdon |
38 55 Bullet And Powder Combinations
Exact component combinations matter immensely when reloading the 38-55 Winchester due to the fragile nature of older rifles and the cartridge’s unique dimensions.
Bullet construction is the first major variable. A solid cast lead bullet creates less friction than a copper jacketed bullet of the same diameter. However, because 38-55 bore diameters vary so widely, a reloader must match the bullet diameter to the rifle. Seating depth also directly influences pressure. Pushing a bullet deeper into the brass reduces internal case capacity.
Brass length is another unique challenge. Modern 38-55 brass is often trimmed to 2.080 inches to standardize it with the modern .375 Winchester, while vintage chambers were cut for brass measuring 2.125 inches. Using the wrong length brass can affect bullet crimping and neck tension. The powder choice must complement the bullet type. Fast burning pistol powders like Unique are strictly for low velocity cast lead target loads, while medium burning rifle powders like IMR 3031 are required to push jacketed bullets to hunting velocities safely.
38 55 Velocity From Published Data
Comparing published 38-55 velocity data showcases the cartridge’s transition from the black powder era to modern smokeless hunting.
- Barnes 255gr JFP: Utilizing 32.0 grains of IMR 3031 yields a manufacturer published maximum muzzle velocity of 1,623 fps out of a 26 inch barrel.
- Remington 255gr JFP:Utilizing a maximum charge of 35.0 grains of IMR 3031 pushes the velocity up to 1,805 fps, though Lyman manuals specify this load is strictly for modern, high strength rifles.
- Lyman 250gr Cast Lead:Utilizing 21.0 grains of H4895 yields a starting velocity of roughly 1,197 fps, perfectly mirroring original 19th century black powder ballistics.
It is important to clearly distinguish manufacturer published velocity derived from controlled environments from independent chronograph testing. Ballistic calculator estimates should never be presented as measured velocity.
38 55 Reloading Data By Barrel Length
Barrel length visibly affects published 38-55 velocity due to the slow burning nature of the black powder it was originally designed to use.
Most historical and modern manufacturer data, including Barnes and Lyman, utilizes a 24 inch or 26 inch barrel as the industry standard for testing 38-55 Winchester loads. The long barrel provides ample time for medium burning rifle powders like Reloder 7 or IMR 3031 to completely combust. When fired from shorter 20 inch carbine barrels, muzzle velocities will drop relative to the published 26 inch barrel data. Shooters must clearly identify the test firearm and barrel length for every velocity figure to set accurate expectations.
38 55 Vintage Target vs Modern Hunting Data
While the terms subsonic and supersonic are rarely used to categorize 38-55 loads, the cartridge is distinctly divided into vintage target loads and modern hunting loads.
Vintage target loads attempt to safely replicate original black powder ballistics. These loads push heavy 250 grain to 265 grain cast lead bullets at lower velocities between 1,100 fps and 1,300 fps. This keeps chamber pressures incredibly low, ensuring safety in antique rifles made before modern steel forging techniques were standardized.
Modern hunting data pushes 200 grain to 255 grain jacketed bullets to velocities between 1,600 fps and 1,800 fps.These loads deliver higher kinetic energy suitable for deer and black bear out to 150 yards.However, publishers explicitly state that these maximum hunting loads are only safe in modern, newly manufactured rifles like recent Winchester Model 94s or Marlin 336s. Data for modern hunting loads cannot be safely transferred to antique actions.
38 55 Energy And Ballistics
Reliable source data shows that the 38-55 Winchester is a highly effective brush cartridge with excellent momentum, despite lacking modern velocities.
A standard 255 grain factory equivalent load leaving the muzzle at 1,320 fps produces roughly 987 foot-pounds of muzzle energy. Because the bullets have a flat nose and low ballistic coefficients, they shed velocity rapidly. At 100 yards, the velocity drops to around 1,190 fps, carrying 802 foot-pounds of energy.
When handloaded to modern maximums, a 255 grain bullet traveling at 1,700 fps increases the muzzle energy significantly, extending the ethical hunting range to approximately 150 yards before the bullet drop becomes too steep to easily compensate for.
Manufacturer Data vs Independent Testing
Manufacturer published reloading data is derived from highly controlled laboratory environments using precise piezoelectric pressure sensors. This data is the only safe benchmark for 38-55 load development.
Independent chronograph testing occurs when reloaders or shooting magazines test handloads in the field. While useful for seeing how historical rifles perform with modern components, these independent measurements often differ from published figures due to variations in bore wear, bullet sizing, and specific rifle chamber tolerances. Reloaders shooting antique firearms must give absolute priority to official, pressure tested manufacturer data to prevent catastrophic firearm failures.
38 55 Pressure And Safety
Following published 38-55 reloading data exactly is critical for safety, especially considering the age of many rifles chambered for this cartridge. The SAAMI standard maximum average pressure is 30,000 CUP, but many vintage rifles cannot safely handle this limit.
Always begin with the published starting load. Never jump straight to the maximum load. The single most important safety step when reloading the 38-55 is slugging the bore of the specific rifle. Firing a cast bullet that is too large for the groove diameter, or firing a modern jacketed bullet through an undersized bore, will drastically and dangerously spike chamber pressure.
Component substitutions are equally dangerous. Swapping a standard large rifle primer for a magnum primer alters the ignition profile. Using shorter modern brass instead of proper vintage length brass changes the case capacity. Always adhere strictly to powder manufacturer specifications and never attempt to develop an unpublished recipe or exceed published maximums to modernize the cartridge’s performance.
Best Sources For 38 55 Reloading Data
The strongest current sources for 38-55 reloading data are the major bullet and powder manufacturers who maintain dedicated obsolete cartridge data.
Lyman Reloading Handbooks, particularly the 47th edition and sections dedicated to obsolete or cast bullet data in newer editions, provide the most comprehensive 38-55 load data chart options available.Barnes Bullets publishes excellent, transparent data specifically for their 255 grain Original JFP utilizing powders like Reloder 7 and IMR 3031. Hodgdon provides reliable data for classic powders like H4895 and H322 in their online data center. Shooters should prioritize these authoritative sources over user submitted forum load reports.
FAQs
Where can I find 38 55 reloading data?
Authoritative 38-55 load data is published in Lyman cast bullet manuals, older editions of the Lyman Reloading Handbook, Barnes official load data sheets, and the Hodgdon online data center.
What powders have published 38-55 data?
Published 38-55 powder profiles frequently utilize medium to fast burning rifle powders like IMR 3031, Reloder 7, IMR 4198, Hodgdon H4895, and Hodgdon H322.
What bullet weights have 38-55 reloading data?
Published data currently supports a range of heavy flat nosed bullet weights, typically spanning from 200 grain jacketed bullets up to 265 grain cast lead bullets.
Does Hodgdon publish 38-55 data?
Yes, Hodgdon publishes 38-55 data for their powder lines, offering specific recipes for H4895, H322, and H4198 among others.
Does Barnes publish 38-55 data?
Yes, Barnes provides highly detailed, published load data tailored specifically to their 255 grain Original Jacketed Flat Point bullet.
What is the difference between starting and maximum 38-55 data?
The starting load is the lowest safe powder charge recommended to cycle the weapon, while the maximum load is the highest tested powder charge that remains within safe pressure limits for the specified firearm type.
Does barrel length affect 38-55 velocity?
Yes. A traditional 26 inch barrel will yield higher velocities and allow for more complete powder combustion than a shorter 20 inch carbine barrel.
Why does 38-55 data vary between sources?
Data varies heavily because publishers use different test platforms, and the 38-55 is notorious for massive variations in original factory bore groove diameters which alters internal friction and pressure.
Where can I find pressure tested 38-55 data?
Pressure tested data is found directly through official reloading manuals published by bullet manufacturers like Barnes and Lyman, which clearly state the safe pressure limits for modern versus antique rifles.