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Enhance your reloading precision with the Sinclair Bump Gage Insert for 338 Lapua, featuring a 20-degree angle for accurate shoulder bump measurements.

SINCLAIR INTERNATIONAL SHOULDER BUMP GAGE INSERT, #20A, 20 DEGREE, 338 LAPUA

050806111257 749011478

Variations

Filters:

Variations:

Enhance your reloading precision with the Sinclair Bump Gage Insert for 338 Lapua, featuring a 20-degree angle for accurate shoulder bump measurements.

SINCLAIR BUMP GAGE INSERT - SHOULDER BUMP GAGE INSERT, #20A, 20 DEGREE, 338 LAPUA

16.9 GBP 0 £16.90 *

Backorderable

Cartridge: 338 Federal, 338 Lapua Mag Product no.: 749011478

Backorderable

16.9 GBP 0 £16.90 *

-11 %

The Sinclair Bump Gage Insert for 220 Swift ensures precise measurements for optimal shoulder bump, enhancing accuracy and consistency in your reloads.

SINCLAIR BUMP GAGE INSERT - SHOULDER BUMP GAGE INSERT, #21, 21 DEGREE, 220 SWIFT

16.9 GBP 2 £16.90 * £18.90

In stock

Cartridge: 220 Swift Product no.: 749011471

In stock

16.9 GBP 2 £16.90 * £18.90

-12 %

The Sinclair Bump Gage Insert #28, 28 degree, is perfect for precise measurement of shoulder bump on 22-250, 223, and 243 cartridges, enhancing your reloading accuracy.

SINCLAIR BUMP GAGE INSERT - SHOULDER BUMP GAGE INSERT, #28, 28 DEGREE, 22-250/223/243

14.9 GBP 7 £14.90 * £16.90

In stock

Cartridge: 22-250 Remington, 223 WSSM (Winchester Super Short Mag), 243 WSSM (Winchester Super Short Mag) Product no.: 749011472

In stock

14.9 GBP 7 £14.90 * £16.90

-11 %

The Sinclair Bump Gage Insert #23 is perfect for precision measuring in the 223 family up to 6mm, ensuring accurate shoulder bump readings for optimal reloading.

SINCLAIR BUMP GAGE INSERT - SHOULDER BUMP GAGE INSERT, #23, 23 DEGREE, 223/22 REM/17 REM

16.9 GBP 11 £16.90 * £18.90

In stock

Cartridge: 223 Remington, 5.56 mm NATO, 221 Remington Fireball, 222 Remington, 17 Remington, 222 Remington Mag Product no.: 749011473

In stock

16.9 GBP 11 £16.90 * £18.90

-12 %

The Sinclair Bump Gage Insert, #26A, offers precise measurement for 6mm Rem/244 cartridges, ensuring optimal shoulder bump for enhanced accuracy.

SINCLAIR BUMP GAGE INSERT - SHOULDER BUMP GAGE INSERT, #26, 26 DEGREE, 6MM

14.9 GBP 8 £14.90 * £16.90

In stock

Cartridge: 6 mm Remington Product no.: 749011474

In stock

14.9 GBP 8 £14.90 * £16.90

-12 %

The Sinclair Bump Gage Insert #35 is designed for precise measurements of the 284 family and WSM cartridges up to .338 Cal, ensuring optimal performance and accuracy.

SINCLAIR BUMP GAGE INSERT - SHOULDER BUMP GAGE INSERT, #35, 35 DEGREE, 30 NOSLER/284/WSM

14.9 GBP 10 £14.90 * £16.90

In stock

Cartridge: 300 WSM (Winchester Short Mag), 270 WSM (Winchester Short Mag), 7 mm WSM (Winchester Short Magnum), 325 WSM (Winchester Short Mag), 284 Winchester, 26 Nosler, 30 Nosler, 33 Nosler, 27 Nosler Product no.: 749011475

In stock

14.9 GBP 10 £14.90 * £16.90

-12 %

The Sinclair Bump Gage Insert #17, designed for the 30-06 family up to 8mm, ensures precise measurements for optimal cartridge fit and performance.

SINCLAIR BUMP GAGE INSERT - SHOULDER BUMP GAGE INSERT, #17, 17 DEGREE, 30-06 SPRINGFIELD

14.9 GBP 11 £14.90 * £16.90

In stock

Cartridge: 30-06 Springfield, 270 Winchester, 25-06 Remington, 7.62 x 39 mm, 280 Remington Product no.: 749011476

In stock

14.9 GBP 11 £14.90 * £16.90

-12 %

The Sinclair Bump Gage Insert for the 308 family features a precise 20-degree angle, ensuring accurate measurements for optimal shoulder bump adjustments.

SINCLAIR BUMP GAGE INSERT - SHOULDER BUMP GAGE INSERT, #20, 20 DEGREE, 308 FAMILY

14.9 GBP 4 £14.90 * £16.90

In stock

Cartridge: 308 Winchester, 243 Winchester, 7 mm - 08 Remington, 7 x 64 mm Brenneke, 260 Remington, 308 Marlin Express, 307 Winchester Product no.: 749011477

In stock

14.9 GBP 4 £14.90 * £16.90

-12 %

The Sinclair Bump Gage Insert features a precise 45-degree shoulder design, ideal for accurately measuring and setting headspace on wildcat cartridges.

SINCLAIR BUMP GAGE INSERT - SHOULDER BUMP GAGE INSERT, #45A, 45 DEGREE, WILDCATS

14.9 GBP 97 £14.90 * £16.90

In stock

Cartridge: 45-60 Winchester Product no.: 749011479

In stock

14.9 GBP 97 £14.90 * £16.90

-13 %

The Sinclair Bump Gage Insert #23A ensures precise measurements for 25-270 caliber cartridges, enhancing accuracy and consistency in your reloading process.

SINCLAIR BUMP GAGE INSERT - SHOULDER BUMP GAGE INSERT, #23A, 23 DEGREE, 25-270 CALIBER

13.9 GBP 2 £13.90 * £15.90

In stock

Cartridge: 6.8 mm Remington SPC Product no.: 749011480

In stock

13.9 GBP 2 £13.90 * £15.90

-12 %

The Sinclair Bump Gage Insert ensures precise measurements for 300 SAUM, 7MM, and 338 calibers, enhancing your reloading accuracy and consistency.

SINCLAIR BUMP GAGE INSERT - SHOULDER BUMP GAGE INSERT, #30A, 30 DEGREE, 300 SAUM/7MM/338

14.9 GBP 29 £14.90 * £16.90

In stock

Cartridge: 6.5 Grendel, 300 Savage, 25 WSSM (Winchester Super Short Mag), 6.5 Creedmoor, 30 Thompson Center, 338 Ruger Compact Magnum, 300 Ruger Compact Magnum, 30 BR (Benchrest), 300 Remington SAUM, 6.5 mm BR Product no.: 749011481

In stock

14.9 GBP 29 £14.90 * £16.90

-12 %

The Sinclair Bump Gage Insert for Ackley Improved 6mm features a precise 40-degree angle, ensuring accurate measurements for optimal reloading performance.

SINCLAIR BUMP GAGE INSERT - SHOULDER BUMP GAGE INSERT, #40, 40 DEGREE, ACKLEY-6MM

14.9 GBP 8 £14.90 * £16.90

In stock

Cartridge: 243 Winchester Ackley Improved, 220 Ackley Improved, 6mm Ackley Improved, 22-250 Ackley Improved, 22-6mm Remington Ackley Improved, 223 Ackley Improved, 6mm/30-30 Ackley Improved, 22/30-30 Ackley Improved, 228 Ackley Magnum Product no.: 749011482

In stock

14.9 GBP 8 £14.90 * £16.90

-12 %

The Sinclair Bump Gage Insert #40A is designed for precise measurement of Ackley Improved to 338 cartridges, ensuring optimal shoulder bump for accuracy.

SINCLAIR BUMP GAGE INSERT - SHOULDER BUMP GAGE INSERT, #40A, 40 DEGREE, 25-338/ACKLEY

14.9 GBP 8 £14.90 * £16.90

In stock

Cartridge: 257 Ackley, 30-30 Ackley, 280 Ackley Improved, 257 Roberts Ackley Improved, 260 Ackley Improved, 257 Roberts +P Ackley Improved, 25-3000 Ackley Improved, 338-06 Ackley Improved, 25 Ackley Krag Short Improved Product no.: 749011483

In stock

14.9 GBP 8 £14.90 * £16.90

-11 %

The Sinclair Bump Gage Insert #30 offers precision measurement for PPC/BR rifles, ensuring optimal shoulder bump for 17 Fireball and 6.5CRD cartridges.

SINCLAIR BUMP GAGE INSERT - SHOULDER BUMP GAGE INSERT, #30, 30 DEGREE, 25R/W/338R/6.5CRD

15.9 GBP 9 £15.90 * £17.90

In stock

Cartridge: 204 Ruger, 22 PPC, 6 PPC, 6 mm XC, 22 BR (Benchrest) Remington, 20 Tactical, 20 PPC, 20 BR (Benchrest), 20 Vartarg, 6 mm BRX, 6mm Creedmoor, 6 mm BR, 22 Nosler, 224 Valkyrie, 22 BRX, 20 Nosler Product no.: 749011484

In stock

15.9 GBP 9 £15.90 * £17.90

-12 %

The Sinclair Bump Gage Insert allows precise measurement for Standard Magnums up to 30 Cal, ensuring optimal performance and accuracy in your firearm.

SINCLAIR BUMP GAGE INSERT - SHOULDER BUMP GAGE INSERT, #25, 25 DEGREE, 225W-338W MAG

14.9 GBP 24 £14.90 * £16.90

In stock

Cartridge: 6.5 x 55 mm Swedish Mauser, 300 Winchester Magnum, 338 Winchester Magnum, 7 mm Remington Magnum, 225 Winchester, 8 mm Remington Mag, 7 mm STW, 30 Remington AR, 264 Winchester Magnum Product no.: 749011485

In stock

14.9 GBP 24 £14.90 * £16.90

13.9 16.9 15 GBP

16.9 GBP £16.90

Prices inclusive of duty & VAT.

Product no.: 749011478

Mfr. No.: 0910201

050806111257 Sinclair Bump Gage Insert, 338 Lapua, 20\

Backorderable

10+

£16.90

Prices inclusive of duty & VAT.

10+

Backorderable, delivery time approx. 4-12 weeks from the USA warehouse.

100-Day Return Policy

Backorderable, delivery time approx. 4-12 weeks from the USA warehouse.

100-Day Return Policy

No charges until we ship

No charge:
Your credit card will not be charged when you place your order.

No commitments:
You are under no obligation until the goods are shipped. You can cancel your order at any time before shipping - free of charge.

Not until shipping:
Your credit card will only be charged once we ship your order. Not before.

Precision shoulder bump measurement
Compatible with 338 Lapua
Durable 20-degree design

Wish List Ask question

13.9 16.9 15 GBP

Description Specification Customers reviews Accessories

SINCLAIR INTERNATIONAL SHOULDER BUMP GAGE INSERT, #20A, 20 DEGREE, 338 LAPUA

16.9 GBP £16.90

Prices inclusive of duty & VAT.

10+

£16.90

Prices inclusive of duty & VAT.

10+

Backorderable, delivery time approx. 4-12 weeks from the USA warehouse.

100-Day Return Policy

Description:

Enhance your precision with the Sinclair Bump Gage Insert!

The Sinclair Bump Gage Insert for the 338 Lapua is an essential tool for any serious shooter or gunsmith. Designed to ensure optimal cartridge fit, this insert guarantees reliability and accuracy in your shooting experience.

Key Features:

Model: #20A
Angle: 20 Degree
Brand: Sinclair International
Compatibility: Specifically designed for 338 Lapua cartridges

This bump gage insert is crafted with precision to help you measure and adjust the shoulder bump of your cartridges, ensuring that they chamber smoothly and consistently. Whether you are reloading for competition or personal use, the Sinclair Bump Gage Insert is a must-have for achieving the best performance from your firearm.

Upgrade your reloading setup today with the Sinclair Bump Gage Insert and experience the difference in your shooting accuracy!

Attributes

Cartridge:
```
338 Lapua Mag
```
,
```
338 Federal
```
Delivery weight: 0.023kg
Shipping height: 1mm
Shipping width: 83mm
Shipping length: 146mm
UPC: 050806111257

Item details

Made in USA

Customers reviews

Customer ratings (17)

3.1 / 5

Not recommended

Does not work for 6.5 Creedmoor 24/07/2018

Bought this 30A to check bumping the shoulders of my 6.5 Creedmoor brass. Had been using a Wilson Case gage to do the job and it works well I thought this may be faster. I bumped and bumped no reading beyond the initial cal of 1.501 on the digital calipers. Each bump i got a new reading on the Wilson Case Gage. Highly disappointed with the purchase.

Definitely recommended

Quality 20/06/2018

I have the original Stoney Point tool and this fits and works well on .338 Lapua Magnum cases to adjust the amount of shoulder bump on cases.

Slightly recommend

Nicely machined doesnât fit without mods 18/04/2018

Iâm using this to measure shoulder bump between fired and full length sized cases. The âthrough holeâ is much too tight on all the 223 fires cases Iâve tried, this leads to cases sticking and readings of .010+ greater than normal. I can neck size to get them to fit but this is an additional step that Iâd prefer not to do, and is impossible to accomplish if Iâm trying to get data while on the range. I asked Sinclairâs techs if there was an issue with the product and they told me to ream it out with a drill bit. Not exactly the answer I was looking for. I would like to keep using this product because I like that the opening matches up with the shoulder angle unlike competing products, but it doesnât work out of the box.

Variations:

SINCLAIR BUMP GAGE INSERT - SHOULDER BUMP GAGE INSERT, #20A, 20 DEGREE, 338 LAPUA

16.9 GBP 0 £16.90 *

Backorderable

Cartridge: 338 Federal, 338 Lapua Mag Product no.: 749011478

Backorderable

16.9 GBP 0 £16.90 *

-11 %

SINCLAIR BUMP GAGE INSERT - SHOULDER BUMP GAGE INSERT, #21, 21 DEGREE, 220 SWIFT

16.9 GBP 2 £16.90 * £18.90

In stock

Cartridge: 220 Swift Product no.: 749011471

In stock

16.9 GBP 2 £16.90 * £18.90

-12 %

SINCLAIR BUMP GAGE INSERT - SHOULDER BUMP GAGE INSERT, #28, 28 DEGREE, 22-250/223/243

14.9 GBP 7 £14.90 * £16.90

In stock

Cartridge: 22-250 Remington, 223 WSSM (Winchester Super Short Mag), 243 WSSM (Winchester Super Short Mag) Product no.: 749011472

In stock

14.9 GBP 7 £14.90 * £16.90

-11 %

SINCLAIR BUMP GAGE INSERT - SHOULDER BUMP GAGE INSERT, #23, 23 DEGREE, 223/22 REM/17 REM

16.9 GBP 11 £16.90 * £18.90

In stock

Cartridge: 223 Remington, 5.56 mm NATO, 221 Remington Fireball, 222 Remington, 17 Remington, 222 Remington Mag Product no.: 749011473

In stock

16.9 GBP 11 £16.90 * £18.90

-12 %

SINCLAIR BUMP GAGE INSERT - SHOULDER BUMP GAGE INSERT, #26, 26 DEGREE, 6MM

14.9 GBP 8 £14.90 * £16.90

In stock

Cartridge: 6 mm Remington Product no.: 749011474

In stock

14.9 GBP 8 £14.90 * £16.90

-12 %

SINCLAIR BUMP GAGE INSERT - SHOULDER BUMP GAGE INSERT, #35, 35 DEGREE, 30 NOSLER/284/WSM

14.9 GBP 10 £14.90 * £16.90

In stock

14.9 GBP 10 £14.90 * £16.90

-12 %

SINCLAIR BUMP GAGE INSERT - SHOULDER BUMP GAGE INSERT, #17, 17 DEGREE, 30-06 SPRINGFIELD

14.9 GBP 11 £14.90 * £16.90

In stock

Cartridge: 30-06 Springfield, 270 Winchester, 25-06 Remington, 7.62 x 39 mm, 280 Remington Product no.: 749011476

In stock

14.9 GBP 11 £14.90 * £16.90

-12 %

SINCLAIR BUMP GAGE INSERT - SHOULDER BUMP GAGE INSERT, #20, 20 DEGREE, 308 FAMILY

14.9 GBP 4 £14.90 * £16.90

In stock

Cartridge: 308 Winchester, 243 Winchester, 7 mm - 08 Remington, 7 x 64 mm Brenneke, 260 Remington, 308 Marlin Express, 307 Winchester Product no.: 749011477

In stock

14.9 GBP 4 £14.90 * £16.90

-12 %

SINCLAIR BUMP GAGE INSERT - SHOULDER BUMP GAGE INSERT, #45A, 45 DEGREE, WILDCATS

14.9 GBP 97 £14.90 * £16.90

In stock

Cartridge: 45-60 Winchester Product no.: 749011479

In stock

14.9 GBP 97 £14.90 * £16.90

-13 %

SINCLAIR BUMP GAGE INSERT - SHOULDER BUMP GAGE INSERT, #23A, 23 DEGREE, 25-270 CALIBER

13.9 GBP 2 £13.90 * £15.90

In stock

Cartridge: 6.8 mm Remington SPC Product no.: 749011480

In stock

13.9 GBP 2 £13.90 * £15.90

-12 %

SINCLAIR BUMP GAGE INSERT - SHOULDER BUMP GAGE INSERT, #30A, 30 DEGREE, 300 SAUM/7MM/338

14.9 GBP 29 £14.90 * £16.90

In stock

14.9 GBP 29 £14.90 * £16.90

-12 %

SINCLAIR BUMP GAGE INSERT - SHOULDER BUMP GAGE INSERT, #40, 40 DEGREE, ACKLEY-6MM

14.9 GBP 8 £14.90 * £16.90

In stock

14.9 GBP 8 £14.90 * £16.90

-12 %

SINCLAIR BUMP GAGE INSERT - SHOULDER BUMP GAGE INSERT, #40A, 40 DEGREE, 25-338/ACKLEY

14.9 GBP 8 £14.90 * £16.90

In stock

14.9 GBP 8 £14.90 * £16.90

-11 %

SINCLAIR BUMP GAGE INSERT - SHOULDER BUMP GAGE INSERT, #30, 30 DEGREE, 25R/W/338R/6.5CRD

15.9 GBP 9 £15.90 * £17.90

In stock

15.9 GBP 9 £15.90 * £17.90

-12 %

SINCLAIR BUMP GAGE INSERT - SHOULDER BUMP GAGE INSERT, #25, 25 DEGREE, 225W-338W MAG

14.9 GBP 24 £14.90 * £16.90

In stock

14.9 GBP 24 £14.90 * £16.90

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-9 %

+ 19 variants

The Sinclair Bullet Comparator Inserts ensure precise ogive-to-base measurements, eliminating wobble and providing consistent results for 17 caliber bullets.

SINCLAIR INTERNATIONAL

BULLET COMPARATOR INSERT, 17 CALIBER (0.171")
BULLET COMPARATOR INSERTS

Bullet Comparators | Bullet Comparator Inserts

Backorderable

£10.90 £9.90 - 12.90

(Select Items on Sale!)

-11 %

+ 2 variants

The Sinclair Comparator and Bump Gauge Body Kit offers precise measurements for bullet seating depth, ensuring accuracy and consistency for optimal shooting performance.

SINCLAIR INTERNATIONAL

COMPARATOR & BUMP GAUGE BODY KIT, STANDARD
SINCLAIR INSERT STYLE BULLET COMPARATOR

Bullet Comparators

3.1

Backorderable

£23.90 £23.90 - 33.90

(Select Items on Sale!)

-9 %

-13 %

+ 21 variants

Accurately measure your rifle's chamber length with the Sinclair Chamber Length Gauge, preventing over-trimming and ensuring optimal case fit for precision reloading.

SINCLAIR INTERNATIONAL

CHAMBER LENGTH GAUGE, 17 CALIBER
Sinclair Chamber Length Gage

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3.4

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£10.90

£9.90 £9.90 - 13.90

(Select Items on Sale!)

-11 %

-13 %

+ 11 variants

Enhance your neck turning precision with Sinclair's stainless steel expander mandrels, designed for perfect fit and ease of use with NT-3000 and NT-1000 tools.

SINCLAIR INTERNATIONAL

STAINLESS STEEL EXPANDER MANDREL, 22 CALIBER (.223")
STAINLESS STEEL EXPANDER MANDRELS

Turning & Expander Mandrels

3.7

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£18.90

£16.90 £13.90 - 16.90

(Select Items on Sale!)

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