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Dormer Pramet A125 21/64 Inch x 310 mm HSS ST STRAIGHT SHANK EXTRA LONG SERIES DRILL BS 328

Dormer Pramet A125 21/64 Inch x 310 mm HSS ST STRAIGHT SHANK EXTRA LONG SERIES DRILL BS 328

SKU:DOR-A12521/64X315

Engineered for deep-hole precision and dependable performance, the Dormer Pramet A125 21/64 Inch x 310 mm HSS Straight Shank Extra Long Series Drill (BS 328) is the go-to choice when reach and rig... Read more ↓
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M
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TypeExtra Long Series
Drill Diameter21/64
Flute Length250
Overall Length310
Shank Diameter8.33
SubstrateHSS
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£64.30
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2 days estimated lead time — subject to availability
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Engineered for deep-hole precision and dependable performance, the Dormer Pramet A125 21/64 Inch x 310 mm HSS Straight Shank Extra Long Series Drill (BS 328) is the go-to choice when reach and rigidity matter. This drill combines a robust starting point with versatile material compatibility, delivering clean holes in a wide range of metals.

Why this drill stands out

  • 118-degree conventional point: A strong, self-centering tip that starts quickly and resists wandering. The geometry is also easy to re-grind, helping you extend tool life between sharpenings.
  • Steam oxide finish: Reduces friction and helps prevent workpiece material from sticking to the cutting edge, promoting smoother chip flow and longer edge life.
  • Extra-long 310 mm length: Specifically designed for drilling very deep holes and applications where extended reach is essential—no need to swap tools mid-task.
  • Premium HSS material: High-speed steel construction delivers strong performance across a variety of metals, including steel, aluminum, and stainless steel, while maintaining good edge retention.
  • Straight shank design: Compatible with standard drill chucks and collets, providing consistent grip and accurate hole alignment on a range of machines.
  • BS 328 compliance: Size and fit meet established standards for reliable interchangeability and predictable performance in professional shops.

Ideal uses and practical benefits

  • Perfect for fabrication, maintenance, and repair tasks that require deep bore holes in long workpieces, frames, or assemblies where access is limited.
  • Well-suited for drilling through mixed materials commonly found in machinery and automotive components, from steel to aluminum and stainless steel.
  • In a production or workshop setting, this drill reduces tooling changes and downtime when deep-hole drilling is a frequent requirement.

Tips for best results

  • Pair with an appropriate spindle speed and feed rate to optimize the 310 mm length—start with conservative speeds and adjust based on material and breakthrough feel.
  • Utilize a steady lubrication or coolant to manage heat buildup and extend tool life, especially when working with stainless steel or alloys.
  • Regularly inspect the cutting edges after re-sharpening to maintain the strong point and ensure consistent hole quality.
Type Extra Long Series
Drill Diameter 21/64
Flute Length 250
Overall Length 310
Shank Diameter 8.33
Substrate HSS
Coated Steam Tempered

What time are Protool open?

We are open Monday to Friday between 8:30am and 5pm.

Do you offer Free Next Day delivery?

Yes! We offer Free Next Day delivery via Royal Mail Tracked 24 on all orders over £50 ex VAT*. We also offer Free DPD Local Next Day delivery on all orders over £100 ex VAT*.

We also offer the following:

  • Royal Mail Tracked 24 — £5.90 (FREE on orders over £50 ex VAT*). Order before 4:30pm for next day delivery. No signature required.
  • DPD Local Next Day — £8.00 (FREE on orders over £100 ex VAT*). Standard next day delivery to UK mainland addresses.
  • Royal Mail Special Delivery — £12.50. Guaranteed delivery before 1pm the next working day.
  • DPD Saturday Delivery — £25.00. Must be ordered on Friday before 4pm. Pre-12pm delivery.

For delivery to Scottish Highlands & Islands, Northern Ireland, Republic of Ireland, or overseas locations, additional charges apply. Please see our delivery page for full details, or call us on 01732 887 334.

*T's & C's and exclusions apply. Please see our delivery page for more information on all our services.

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Staff are very helpful and interested in providing a good service making us the customer feel valued.
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Full Range: Dormer Pramet A125 HSS ST STRAIGHT SHANK EXTRA LONG SERIES DRILLS BS 328

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You are viewing DOR-A12521/64X315. Click any other SKU to view its full details.

Product SKUDrill DiameterFlute LengthOverall LengthShank DiameterPriceStock Order
DOR-A1251.4X160 1.401001601.4£18.83 2 days
DOR-A1251.5X125 1.50801251.5£10.72 2 days
DOR-A1251.5X160 1.501001601.5£12.72 2 days
DOR-A1251/16X125 1/16801251.59£13.07 2 days
DOR-A1251/16X160 1/161001601.59£15.64 2 days
DOR-A1251.8X160 1.801001601.8£16.45 2 days
DOR-A1255/64X160 5/641001601.98£16.14 2 days
DOR-A1255/64X125 5/64801251.98£15.49 2 days
DOR-A1252.0X125 2.00801252£8.30 2 days
DOR-A1252.0X160 2.001001602£9.76 2 days
DOR-A1252.2X160 2.201001602.2£10.11 2 days
DOR-A1253/32X160 3/321001602.38£9.79 2 days
DOR-A1253/32X125 3/32801252.38£8.94 2 days
DOR-A1252.5X125 2.50801252.5£7.84 2 days
DOR-A1252.5X160 2.501001602.5£9.65 2 days
DOR-A1257/64X125 7/64801252.78£9.47 2 days
DOR-A1257/64X160 7/641001602.78£14.50 2 days
DOR-A1253.0X160 3.001001603£9.17 2 days
DOR-A1253.0X200 3.001502003£12.25 2 days
DOR-A1253.0X250 3.002002503£15.53 2 days
DOR-A1251/8X160 1/81001603.18£11.26 2 days
DOR-A1251/8X200 1/81502003.18£11.45 2 days
DOR-A1251/8X250 1/82002503.18£22.28 2 days
DOR-A1251/8X315 1/82503103.18£25.63 2 days
DOR-A1253.3X160 3.301001603.3£13.22 2 days
DOR-A1253.5X160 3.501001603.5£9.30 2 days
DOR-A1253.5X200 3.501502003.5£11.48 2 days
DOR-A1253.5X250 3.502002503.5£16.17 2 days
DOR-A1259/64X160 9/641001603.57£16.32 2 days
DOR-A1259/64X200 9/641502003.57£16.42 2 days
DOR-A1259/64X315 9/642503103.57£23.76 2 days
DOR-A1255/32X160 5/321001603.97£11.43 2 days
DOR-A1255/32X200 5/321502003.97£13.53 2 days
DOR-A1255/32X250 5/322002503.97£26.08 2 days
DOR-A1255/32X315 5/322503103.97£33.11 2 days
DOR-A1254.0X160 4.001001604£9.33 2 days
DOR-A1254.0X200 4.001502004£12.04 2 days
DOR-A1254.0X250 4.002002504£16.13 2 days
DOR-A1254.0X315 4.002503104£20.00 2 days
DOR-A12511/64X160 11/641001604.37£15.03 2 days
DOR-A12511/64X200 11/641502004.37£18.10 2 days
DOR-A12511/64X315 11/642503104.37£26.08 2 days
DOR-A1254.5X160 4.501001604.5£10.84 2 days
DOR-A1254.5X200 4.501502004.5£14.21 2 days
DOR-A1254.5X250 4.502002504.5£21.78 2 days
DOR-A1254.5X315 4.502503104.5£23.80 2 days
DOR-A1253/16X160 3/161001604.76£10.99 2 days
DOR-A1253/16X200 3/161502004.76£12.52 2 days
DOR-A1253/16X250 3/162002504.76£15.94 2 days
DOR-A1253/16X315 3/162503104.76£23.30 2 days
DOR-A1253/16X400 3/163004004.76£44.05 2 days
DOR-A1255.0X160 5.001001605£10.53 2 days
DOR-A1255.0X200 5.001502005£13.86 2 days
DOR-A1255.0X250 5.002002505£17.24 2 days
DOR-A1255.0X315 5.002503105£23.89 2 days
DOR-A1255.0X400 5.003004005£30.42 2 days
DOR-A12513/64X200 13/641502005.16£21.57 2 days
DOR-A12513/64X250 13/642002505.16£27.95 2 days
DOR-A12513/64X315 13/642503105.16£36.71 2 days
DOR-A1255.5X200 5.501502005.5£12.84 2 days
DOR-A1255.5X250 5.502002505.5£20.75 2 days
DOR-A1255.5X315 5.502503105.5£32.83 2 days
DOR-A1257/32X200 7/321502005.56£16.69 2 days
DOR-A1257/32X250 7/322002505.56£21.33 2 days
DOR-A12515/64X200 15/641502005.95£25.86 2 days
DOR-A12515/64X315 15/642503105.95£24.81 2 days
DOR-A1256.0X200 6.001502006£14.91 2 days
DOR-A1256.0X250 6.002002506£19.96 2 days
DOR-A1256.0X315 6.002503106£24.85 2 days
DOR-A1256.0X400 6.003004006£36.16 2 days
DOR-A1251/4X200 1/41502006.35£16.32 2 days
DOR-A1251/4X250 1/42002506.35£20.69 2 days
DOR-A1251/4X315 1/42503106.35£25.63 2 days
DOR-A1251/4X400 1/43004006.35£52.44 2 days
DOR-A1251/4X500 1/44004606.35£72.96 2 days
DOR-A1256.5X200 6.501502006.5£17.10 2 days
DOR-A1256.5X250 6.502002506.5£21.20 2 days
DOR-A1256.5X315 6.502503106.5£30.64 2 days
DOR-A12517/64X200 17/641502006.75£21.11 2 days
DOR-A12517/64X250 17/642002506.75£28.41 2 days
DOR-A12517/64X500 17/644004606.75£72.96 2 days
DOR-A1257.0X200 7.001502007£18.45 2 days
DOR-A1257.0X250 7.002002507£23.58 2 days
DOR-A1257.0X315 7.002503107£33.24 2 days
DOR-A1257.5X200 7.501502007.5£22.12 2 days
DOR-A1257.5X250 7.502002507.5£26.68 2 days
DOR-A1257.5X315 7.502503107.5£34.56 2 days
DOR-A1255/16X200 5/161502007.94£20.93 2 days
DOR-A1255/16X250 5/162002507.94£26.36 2 days
DOR-A1255/16X315 5/162503107.94£34.88 2 days
DOR-A1255/16X500 5/164004607.94£86.18 2 days
DOR-A1258.0X250 8.002002508£26.04 2 days
DOR-A1258.0X315 8.002503108£35.07 2 days
DOR-A1258.0X400 8.003004008£44.23 2 days
DOR-A12521/64X315 Viewing21/642503108.33£64.30 2 days
DOR-A1258.5X250 8.502002508.5£35.66 2 days
DOR-A1258.5X315 8.502503108.5£47.88 2 days
DOR-A12511/32X250 11/322002508.73£34.06 2 days
DOR-A12511/32X315 11/322503108.73£58.37 2 days
DOR-A12511/32X400 11/323004008.73£72.05 2 days
DOR-A12511/32X500 11/324004608.73£86.18 2 days
DOR-A1259.0X250 9.002002509£30.87 2 days
DOR-A1259.0X315 9.002503109£39.31 2 days
DOR-A1259.0X400 9.003004009£56.54 2 days
DOR-A1259.5X250 9.502002509.5£36.98 2 days
DOR-A1259.5X315 9.502503109.5£49.70 2 days
DOR-A1253/8X250 3/82002509.52£33.61 2 days
DOR-A1253/8X315 3/82503109.52£42.59 2 days
DOR-A1253/8X400 3/83004009.52£53.81 2 days
DOR-A1253/8X500 3/84004609.52£74.33 2 days
DOR-A12510.0X250 10.0020025010£35.52 2 days
DOR-A12510.0X315 10.0025031010£44.19 2 days
DOR-A12510.0X400 10.0030040010£65.21 2 days
DOR-A12513/32X250 13/3220025010.32£44.32 2 days
DOR-A12513/32X315 13/3225031010.32£54.72 2 days
DOR-A12510.5X250 10.5020025010.5£44.28 2 days
DOR-A12510.5X315 10.5025031010.5£57.46 2 days
DOR-A12510.5X400 10.5030040010.5£68.86 2 days
DOR-A12511.0X250 11.0020025011£40.04 2 days
DOR-A12511.0X315 11.0025031011£51.07 2 days
DOR-A12511.0X400 11.0030040011£63.38 2 days
DOR-A1257/16X250 7/1620025011.11£49.25 2 days
DOR-A1257/16X315 7/1625031011.11£62.02 2 days
DOR-A1257/16X400 7/1630040011.11£129.05 2 days
DOR-A12529/64X315 29/6425031011.51£57.46 2 days
DOR-A12512.0X250 12.0020025012£46.97 2 days
DOR-A12512.0X315 12.0025031012£54.72 2 days
DOR-A12512.0X400 12.0030040012£73.42 2 days
DOR-A12531/64X315 31/6425031012.3£57.46 2 days
DOR-A1251/2X250 1/220025012.7£57.00 2 days
DOR-A1251/2X315 1/225031012.7£72.96 2 days
DOR-A1251/2X400 1/230040012.7£95.76 2 days
DOR-A12513.0X315 13.0025031013£58.37 2 days
DOR-A12513.0X400 13.0030040013£74.33 2 days
DOR-A12517/32X315 17/3225031013.49£58.37 2 days
DOR-A12514.0X315 14.0025031014£69.31 2 days
DOR-A12514.0X400 14.0030040014£81.17 2 days
DOR-A1259/16X315 9/1625031014.29£69.31 2 days
DOR-A12537/64X315 37/6425031014.68£69.31 2 days
DOR-A12519/32X315 19/3225031015.08£69.31 2 days
DOR-A12519/32X500 19/3240046015.08£93.02 2 days
DOR-A1255/8X315 5/825031015.88£69.31 2 days
DOR-A1255/8X500 5/840046015.88£93.02 2 days
DOR-A12511/16X315 11/1625031017.46£69.31 2 days
DOR-A1253/4X315 3/425031019.05£70.68 2 days
DOR-A1253/4X500 3/440046019.05£95.30 2 days

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