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Message: <blockquote data-quote="Lycanthrope" data-source="post: 469629" data-attributes="member: 562">Unfortunately I didnt think about bullet stability when I ordered these bullets and my 1/10 twist 308 likely wont stabilize the bullets I ordered at subsonic speeds. According to AI I should aim for about 1300fps to stabilize them out to 200 yards. Ill shoot suppressed so it will still be fairly quiet. Here is some load data AI generated for me:Initial Load Development for .308 Win with 200 gr Copper Bullet and Blue DotBlue Dot (Alliant) is a suitable choice for reduced-velocity loads in .308 Winchester due to its progressive burn rate, which helps maintain consistent ignition in underfilled cases (critical for ~1,300 fps to avoid erratic pressures or stuck bullets). However, no official published load data exists from Hodgdon/Alliant for this exact combination (200 gr bullet, Blue Dot)—their manuals focus Blue Dot on pistol/revolver loads or lighter rifle bullets. The recommendations below are extrapolated from user-reported data, forums (e.g., AfricaHunting, The High Road, Accurate Shooter), and similar reduced loads with heavy bullets (180-220 gr) in .308 Win. These are starting points only—treat as experimental and use at your own risk. Always prioritize safety: Start low, work up in 0.3-0.5 gr increments, check for pressure signs (e.g., flattened primers, sticky extraction), and use a chronograph to verify velocity.Estimated Powder Charge Range<ul> <li data-xf-list-type="ul">Starting Charge: 13.0 grains (conservative; ~1,100-1,200 fps expected, based on Red Dot analogs and Blue Dot's ~20-30% slower burn).</li> <li data-xf-list-type="ul">Test Range: 13.0 - 16.0 grains (in 0.5 gr steps: 13.0, 13.5, 14.0, 14.5, 15.0, 15.5, 16.0). This should bracket ~1,200-1,500 fps, allowing you to fine-tune to 1,300 fps.</li> <li data-xf-list-type="ul">Maximum Safe Estimate: Do not exceed 17.0 grains without further data (e.g., QuickLOAD simulation); pressures could approach 25,000-30,000 PSI, still well below .308 SAAMI max (62,000 PSI), but monitor closely.</li> </ul>Expected Velocities (Approximate, 24" Barrel)Based on user reports and burn rate scaling from similar loads (e.g., 14 gr Blue Dot with 165 gr cast ~1,400-1,600 fps; adjusted for heavier bullet and reduced goal):<table style='width: 100%'><tr><th>Charge (gr)</th><th>Est. Velocity (fps)</th><th>Notes</th></tr><tr><td>13.0</td><td>1,100-1,200</td><td>Subsonic baseline; low pressure (~15,000-20,000 PSI); good for initial stability tests.</td></tr><tr><td>14.0</td><td>1,200-1,300</td><td>Target zone for your 1,300 fps goal; ~20% case fill—use visual checks for double-charges.</td></tr><tr><td>15.0</td><td>1,300-1,400</td><td>Likely hits 1,300 fps; increasing accuracy potential.</td></tr><tr><td>16.0</td><td>1,400-1,500</td><td>Upper end; watch for sooting or velocity spikes.</td></tr></table>Loading and Testing Guidelines<ul> <li data-xf-list-type="ul">Components: Use standard large rifle primers (e.g., CCI 200); COAL ~2.800-2.810" for your 1.4" copper bullet (e.g., Barnes TSX). Crimp lightly if using a suppressor.</li> <li data-xf-list-type="ul">Safety Tips:<ul> <li data-xf-list-type="ul">Case Fill: These are ~15-25% fill—visually inspect every round for proper charge (no double-loads; a double would be obvious but dangerous).</li> <li data-xf-list-type="ul">Work-Up: Fire 3-5 rounds per charge from a safe distance. Chronograph each group. Stop if velocity jumps >50 fps or shows inconsistency (indicating ignition issues).</li> <li data-xf-list-type="ul">Stability: With your 1:10 twist, 1,300 fps should yield SG ~1.3 (as calculated previously)—test groups at 100/200 yards for keyholing.</li> <li data-xf-list-type="ul">Alternatives if Needed: If Blue Dot underperforms (e.g., inconsistent ES/SD >30 fps), consider H4895 (start at 60% of max: ~24.6 gr for ~1,000-1,200 fps) or Trail Boss for better fill.</li> </ul></li> <li data-xf-list-type="ul">Resources: Cross-reference with QuickLOAD software if available, or forums like Accurate Shooter for user chrony data. Consult the Alliant Powder website for general reduced-load warnings.</li> </ul>Once chronographed, share results for further refinement! Remember, reloading is iterative—prioritize safety over speed.</blockquote>

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