32 Remington Cartridge Conversions

[7000grain]

Brass Conversion Guide Using Herters 234 Press and Sinclair Expander Mandrels
This comprehensive guide outlines detailed processes for converting brass cases using a Herters 234 turret press, Sinclair expander mandrels, mini lathe, and brass annealer. Expanding case necks in stages minimizes work hardening and reduces the risk of case failures.
Required Equipment Setup
Herters 234 Press Setup
The Herters 234 turret press requires specific preparation for optimal performance in case conversion work:
Setting up the press correctly is essential for precise brass conversion work. The Herters 234 press has a sturdy design that makes it ideal for reforming operations, though it does come with some unique characteristics. The press features a slanted ram which can be adjusted using a wedge support for more precise alignment. For brass conversion work, securing the turret plate is critical - ensure the large nut above the turret is properly tightened, and remember that the detent ball and spring are located 180 degrees from the ram on the back side.
Shell holder compatibility is a consideration with Herters presses. You’ll need either original Herters shell holders or appropriate adapters from RCBS or C&H4D that fit the press ram. If using an adapter, be careful not to overtighten the retaining screws at the top of the ram as this could spread the ram top.
The turret design allows you to mount multiple dies simultaneously, which is particularly advantageous for case conversion processes that require sequential operations. Position your dies in logical order around the turret plate to minimize handling between steps.
Sinclair Expander Mandrel Setup
Sinclair expander mandrels require careful selection and installation for proper case expansion:
The Sinclair expander die system consists of a die body and interchangeable mandrels of different diameters. For rifle cartridges like our examples, you’ll need the 17 through 338 caliber expander die (part number 749-001-715WB).
For proper installation, unthread the knurled die cap, drop the appropriate mandrel into the expander die, and reinsert the cap. The o-ring in the die cap allows the mandrel to float and self-center within the case neck. The mandrel should be fully captured within the die to prevent pulling out under pressure.
For our conversions, you’ll need to select the appropriate mandrel sizes. Standard expander mandrels are typically 0.001” under bullet diameter, while turning mandrels are 0.002” under. For the .32 Remington (which uses .321” bullets), you would need a .320” expander mandrel.
When setting up the expander die in your press, adjust the die height so that when a case is fully raised in the press, the mandrel penetrates to the appropriate depth in the neck. Using a marking method (like a Sharpie or graphite on the mandrel) helps visualize proper depth penetration.
Case Conversion: 30 Remington to 32 Remington
Converting from 30 Remington to 32 Remington is relatively straightforward as they share the same case dimensions except for neck diameter. This is a simpler process that primarily involves neck expansion:
Step 1: Initial Inspection and Preparation
1. Inspect all 30 Remington brass for defects, cracks, or excessive wear.
2. Measure case length (should be approximately 2.105”) and trim to uniform length if necessary.
3. Check case head thickness using calipers (minimum thickness should be 0.175”).
4. Clean brass thoroughly to remove dirt and oxidation.
Step 2: Depriming
1. Install a universal decapping die in your Herters 234 press.
2. Carefully decap all cases without resizing them.
3. Clean primer pockets and inspect for any damage.
Step 3: Annealing
1. Set up your annealer according to manufacturer specifications.
2. Focus flame on the neck/shoulder junction area for 5-8 seconds until the brass reaches a dull red color (approximately 650°F).
3. Allow cases to cool naturally by placing them neck-up on a non-flammable surface.
4. This process softens the brass, making it more ductile for the expansion process and extending case life.
Step 4: Staged Neck Expansion
1. Install the Sinclair expander die body with a .308” mandrel (for 30 caliber) in your Herters 234 press.
2. Apply a light coating of case lubricant to the inside of the case neck.
3. Carefully expand the neck by raising the ram slowly and completely.
4. Replace with a .315” intermediate mandrel and repeat the process.
5. Finally, use a .320” mandrel to achieve the final desired neck diameter for .32 Remington.
6. Between expansions, check for signs of neck splitting or excessive thinning.
Step 5: Full-Length Sizing
1. Install a .32 Remington full-length sizing die in your Herters 234 press.
2. Apply case lubricant to the entire case body.
3. Run each case through the full-length die to finalize dimensions.
4. Ensure the sizing die is set to just bump the shoulder back by 0.001-0.002”.
Step 6: Final Inspection and Processing
1. Check neck wall thickness with a micrometer or caliper for consistency.
2. Verify inside neck diameter with expansion gauges (should be approximately 0.320”).
3. Chamfer the inside and outside of the case mouth.
4. Perform a final cleaning to remove lubricant.
5. Test fit a .321” bullet to verify proper neck tension.
Case Conversion: 30-30 Winchester to 32 Remington
Converting 30-30 Winchester to 32 Remington is more complex due to differences in the case head. This process requires rim modification using a mini lathe:
Step 1: Initial Measurements and Preparation
1. Measure the original 30-30 brass dimensions: rim diameter (approximately 0.506”), case head diameter (approximately 0.422”), and case length (approximately 2.039”).
2. Measure the internal case depth from the mouth to the web using calipers – subtract this from the overall length to verify adequate head thickness (minimum 0.175”).
3. Clean brass thoroughly to remove dirt and oxidation.
Step 2: Case Head Modification Using Mini Lathe
1. Set up your mini lathe with appropriate collet or chuck to hold the case.
2. Mount the 30-30 case with the mouth toward the tailstock.
3. Using a sharp cutting tool, carefully turn down the rim to match case body diameter (approximately 0.422”).
4. Cut an extractor groove approximately 0.050” from the case head, 0.050” wide, and 0.010” deep.
5. Ensure consistent dimensions across all cases by taking periodic measurements.
6. Deburr any sharp edges with fine sandpaper or a deburring tool.
Step 3: Depriming
1. Install a universal decapping die in your Herters 234 press.
2. Carefully decap all cases without resizing.
3. Clean primer pockets and inspect for case head integrity.
Step 4: Annealing
1. Set up your annealer according to manufacturer specifications.
2. Heat the neck/shoulder junction area for 5-8 seconds until the brass reaches a dull red color.
3. Allow cases to cool naturally by placing them neck-up on a non-flammable surface.
4. Annealing softens the brass, which is particularly important after machining work.
Step 5: Staged Neck Expansion
1. Install the Sinclair expander die with a .308” mandrel in the Herters 234 press.
2. Apply a light coating of case lubricant to the inside of the case neck.
3. Carefully expand the neck by raising the ram slowly and completely.
4. Replace with a .315” intermediate mandrel and repeat the process.
5. Finally, use a .320” mandrel to achieve the final neck diameter for .32 Remington.
6. Between expansions, check for signs of neck splitting or excessive thinning.
Step 6: Full-Length Sizing and Fire-Forming
1. Install a .32 Remington full-length sizing die in your Herters 234 press.
2. Apply case lubricant to the entire case body.
3. Run each case through the full-length die to finalize dimensions.
4. For fire-forming, load with a reduced charge (approximately 70% of standard load) and consider using filler like cream of wheat to prevent case collapse.
5. Fire in your .32 Remington firearm to complete the forming process.
Step 7: Final Inspection and Quality Control
1. After fire-forming, inspect cases for proper expansion and any signs of weakness.
2. Check neck wall thickness with a micrometer for consistency.
3. Verify case head measurements and extractor groove dimensions.
4. Chamfer the inside and outside of the case mouth.
5. Test for proper feeding and extraction in your firearm before loading full-power rounds.
Special Considerations
When converting brass for the 32 Remington, be aware that some barrels have been found with bores as small as .319”, so slug your barrel to determine the exact diameter. This will help you select the optimal bullet size and final neck dimension.
The Herters 234 press is particularly well-suited for brass conversion work due to its multiple stations. Consider installing dies in logical sequence to minimize handling: decapping die, sizing die, and expander dies with progressively larger mandrels.
Annealing between major forming steps helps maintain brass ductility and prevents case neck splits. For optimal results, anneal cases after significant reforming operations and every 3-5 reloadings thereafter. This practice resulted in approximately 11% improved accuracy in controlled testing.
Remember that properly converted brass typically delivers excellent performance, but maintain vigilance with inspections, particularly for the first few firings. Always begin with reduced loads when using converted brass and work up gradually while monitoring for pressure signs.
Conclusion
These brass conversion processes enable you to create custom ammunition for obsolete cartridges like the 32 Remington. While commercial brass may be available for purchase at premium prices (approximately $1.00 per case), these conversion techniques provide a cost-effective alternative for shooters looking to breathe new life into classic firearms. The multi-stage expansion approach minimizes the risk of case failures while the precise lathe work ensures proper headspacing and extraction in your firearm.