The 10mm Auto cartridge, known for its potent power and versatility, has gained significant popularity among handgun enthusiasts. Reloading your own 10mm ammunition offers a degree of customization unavailable with factory rounds, allowing you to tailor your loads to your specific firearm and shooting style. This guide focuses on Longshot powder, a popular choice for 10mm reloaders due to its excellent performance and relatively clean burn. We'll delve into safe reloading practices, specific load data, and considerations for various bullet weights. Remember: Always consult your firearm's manual for maximum pressure limits before attempting any reloading. Safety is paramount.
Understanding Longshot Powder for 10mm
Longshot is a relatively slow-burning extruded powder, making it ideal for larger pistol cartridges like the 10mm. Its burn rate characteristics contribute to consistent performance across a range of bullet weights and case volumes. This translates to reliable accuracy and reduced pressure spikes, crucial for maintaining the longevity of your firearm. However, its slow burn rate means it's not suitable for all 10mm applications, particularly those using lighter bullets.
Key Characteristics of Longshot:
- Extruded: Offers better metering consistency compared to spherical powders.
- Slow Burning: Suitable for heavier bullets and longer barrels.
- Clean Burning: Produces less fouling in your firearm compared to some other powders.
- Versatile: Works well with a variety of bullet weights and case brands.
Safe Reloading Practices: A Foundation for Success
Before we discuss specific load data, let's reiterate the importance of safe reloading practices. Improper reloading techniques can lead to dangerous over-pressure situations, potentially resulting in serious injury or firearm damage.
Essential Safety Precautions:
- Consult your firearm's manual: This document contains crucial information regarding maximum pressure limits for your specific firearm model. Exceeding these limits can be disastrous.
- Use a quality reloading press and dies: Invest in reputable equipment that's in good working condition.
- Use a scale to accurately measure powder charges: Consistent powder charges are critical for safe and accurate ammunition. Never estimate.
- Wear safety glasses and hearing protection: These protect your eyes and hearing from potential hazards during the reloading process.
- Work in a clean, well-lit area: A cluttered workspace can lead to mistakes.
- Only load one round at a time: This reduces the chance of loading errors and improves safety.
- Double-check your work: Always visually inspect each round before loading it into your magazine or cylinder.
Longshot 10mm Load Data: A Starting Point
The following data is provided as a starting point. Always start at the minimum charge weight and work your way up gradually, carefully monitoring pressure signs. These are sample loads and may not be suitable for all firearms. Always cross-reference this data with published data from reputable sources like Hodgdon, Alliant, or your firearm's manual. These examples assume the use of new, once-fired brass cases.
Note: This table is for illustrative purposes only and should not be considered exhaustive or a substitute for consulting reliable reloading manuals. Always verify load data with multiple sources and start at the minimum load.
| Bullet Weight (grains) | Bullet Type | Case Type | Powder (Longshot) (grains) | COL (inches) | Notes |
|---|---|---|---|---|---|
| 180 | Jacketed Hollow Point (JHP) | Starline | 8.5 - 9.5 | 1.260 - 1.275 | Start low, work up |
| 200 | Jacketed Hollow Point (JHP) | Starline | 9.0 - 10.0 | 1.265 - 1.280 | Start low, work up |
| 200 | Full Metal Jacket (FMJ) | Starline | 8.8 - 9.8 | 1.265 - 1.280 | Start low, work up |
| 220 | Jacketed Hollow Point (JHP) | Starline | 9.5 - 10.5 | 1.270 - 1.285 | Start low, work up |
COL (Cartridge Overall Length): This measurement is crucial for ensuring proper chambering and preventing malfunctions. Always double-check your COL with a cartridge gauge.
Observing Pressure Signs: A Critical Skill
As you work your way up in powder charge weight, carefully monitor your ammunition for signs of excessive pressure. These signs can include:
- Difficult cycling: The firearm might be difficult to cycle manually or fail to cycle completely.
- Excessive recoil: More recoil than expected could indicate over-pressure.
- Flat primers: Primers that are flattened excessively could be indicative of high pressure.
- Case head separation: This is a serious indication of catastrophic over-pressure. Never continue loading if this happens.
- Bullet setback: The bullet might be pushed back into the case due to high pressure.
Conclusion: Responsible Reloading with Longshot
Reloading your 10mm ammunition with Longshot powder can offer significant advantages in terms of cost savings and performance customization. However, responsible and safe reloading practices are paramount. This guide provides a starting point for your reloading journey. Always consult reputable reloading manuals, start with minimum load data, and carefully monitor for signs of excessive pressure. Remember, safety should always be your top priority. Happy and safe reloading!