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Dormer Pramet A125 5.00 mm x 400 mm HSS ST STRAIGHT SHANK EXTRA LONG SERIES DRILL BS 328

Dormer Pramet A125 5.00 mm x 400 mm HSS ST STRAIGHT SHANK EXTRA LONG SERIES DRILL BS 328

SKU:DOR-A1255.0X400

Dormer Pramet A125 5.00 mm x 400 mm HSS Straight Shank Extra Long Series Drill BS 328 is engineered for deep-hole precision and dependable performance in a range of metals. Built around a high-spe... Read more ↓
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M
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TypeExtra Long Series
Drill Diameter5.00
Flute Length300
Overall Length400
Shank Diameter5
SubstrateHSS
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£30.42
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Dormer Pramet A125 5.00 mm x 400 mm HSS Straight Shank Extra Long Series Drill BS 328 is engineered for deep-hole precision and dependable performance in a range of metals. Built around a high-speed steel core, this extra-long drill is the go-to choice when reach matters as much as cutting power.

Key features that deliver reliable results

  • 118° conventional point provides a strong start and remains easy to re-sharpen in the workshop, helping you maintain accuracy and reduce drift during setup. This geometry supports clean entry into harder materials and predictable hole alignment.
  • Steam oxide finish minimizes material adhesion at the cutting edge, promoting smoother chip flow and reducing built-up edge when drilling steel, aluminum, and stainless steel. The finish also contributes to wear resistance in demanding drilling tasks.
  • Extra-long length for deep holes with an overall length of 400 mm and a flute length of 300 mm, designed specifically for applications where access is constrained or deep hole drilling is required. BS 328-compliant, this drill maintains rigidity and accuracy over long reach.
  • Premium HSS material provides versatile performance across a range of common metals—including steel, aluminum, and stainless steel—without sacrificing edge durability or cutting speed. This makes the A125 series a reliable workhorse for fabrication, maintenance, and workshop environments.
  • Straight shank for universal mounting compatibility with standard drill chucks and collets on manual and CNC machines, ensuring straightforward setup and repeatable results across gear benches and production lines.
  • BS 328 compliance confirms the tool’s dimensional standards for consistent interchangeability in professional settings, so you can source confidently from trusted suppliers.

What this drill is ideal for

  • Deep-hole drilling in steel structures, automotive components, machinery housings, and fabrication frames where a standard-length drill would fall short.
  • Projects that require long reach without compromising straightness or chip evacuation, such as drilling through thick plates or stacked assemblies.
  • General-purpose steel, aluminum, and stainless steel drilling on both manual drill presses and CNC machines, where a robust, grindable point and durable edge are advantageous.

Practical guidance to maximize performance

  • For best results, keep feed rates conservative on deep holes and allow the 10xD drilling depth (where applicable) to proceed in a controlled, peck-free manner unless your material requires progressive pecking. This approach helps maintain edge life and hole accuracy. (10xD depth is a common guideline associated with this extra-long A125 series.)
  • Because the A125.5x400 series is designed without through-coolant channels, plan your cooling strategy accordingly—apply coolant at the cutting zone to reduce heat and extend tool life, or rely on dry cutting where appropriate for your material and machine setup.
  • Use a sharp, properly indexed regrinding routine to preserve the 118° point angle, ensuring consistent starts and reducing chatter on hard or uneven workpieces.

With the Dormer Pramet A125 5.00 mm x 400 mm HSS Straight Shank Extra Long Series Drill BS 328, you’re equipping your workshop with a trustworthy, long-reach tool that blends precise geometry, wear-resisting finish, and broad material compatibility for everyday metalworking challenges. Whether you’re tackling automotive components, structural steel work, or precision enclosures, this drill delivers depth, control, and repeatable performance—time after time.

Type Extra Long Series
Drill Diameter 5.00
Flute Length 300
Overall Length 400
Shank Diameter 5
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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Full Range: Dormer Pramet A125 HSS ST STRAIGHT SHANK EXTRA LONG SERIES DRILLS BS 328

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You are viewing DOR-A1255.0X400. 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 Viewing5.003004005£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 21/642503108.33£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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