Your basket is empty.

Basket

Help and contact

Free standard delivery over £199

100-day return policy

Newsletter

Sale

Over 300,000 customers - we say thank you!

4.93/5 "Very good" (1400+ reviews)

40,000+ products for hunting and shooting sports

The Sinclair Chamber Length Gage accurately measures your rifle's chamber length, ensuring precise case trimming for optimal performance in reloading.

-7 %

SINCLAIR INTERNATIONAL CHAMBER LENGTH GAUGE, 30 CALIBER

749000804

Variations

Filters:

Variations:

-7 %

The Sinclair Chamber Length Gage accurately measures your rifle's chamber length, ensuring precise case trimming for optimal performance in reloading.

Sinclair Chamber Length Gage - CHAMBER LENGTH GAUGE, 30 CALIBER

12.9 GBP 21 £12.90 * £13.90

In stock

Caliber: 30 Caliber (.308) Product no.: 749000804

In stock

12.9 GBP 21 £12.90 * £13.90

-9 %

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 Chamber Length Gage - CHAMBER LENGTH GAUGE, 17 CALIBER

9.9 GBP 1 £9.90 * £10.90

In stock

Caliber: 17 Caliber (.172) Product no.: 749000746

In stock

9.9 GBP 1 £9.90 * £10.90

-7 %

The Sinclair Chamber Length Gauge accurately measures your rifle's chamber length, ensuring precise case trimming and preventing over-trimming for optimal performance.

Sinclair Chamber Length Gage - CHAMBER LENGTH GAUGE, 20 CALIBER

12.9 GBP 1 £12.90 * £13.90

In stock

Caliber: 20 Caliber (.204) Product no.: 749000795

In stock

12.9 GBP 1 £12.90 * £13.90

-8 %

Accurately measure your rifle's chamber length with the Sinclair Chamber Length Gage, ensuring optimal case trimming and improved reload precision.

Sinclair Chamber Length Gage - CHAMBER LENGTH GAUGE, 22 CALIBER

11.9 GBP 21 £11.90 * £12.90

In stock

Caliber: 22 Caliber (.223-.224) Product no.: 749000811

In stock

11.9 GBP 21 £11.90 * £12.90

-7 %

The Sinclair Chamber Length Gauge accurately measures your rifle's chamber length, preventing over-trimming and ensuring optimal cartridge fit for precision reloading.

Sinclair Chamber Length Gage - CHAMBER LENGTH GAUGE, 25 CALIBER

12.9 GBP 1 £12.90 * £13.90

In stock

Caliber: 25 Caliber (.257) Product no.: 749000771

In stock

12.9 GBP 1 £12.90 * £13.90

-7 %

The Sinclair Chamber Length Gauge accurately measures your rifle's chamber length, helping prevent over-trimming cases for optimal reloading performance.

Sinclair Chamber Length Gage - CHAMBER LENGTH GAUGE, 270 CALIBER

12.9 GBP 8 £12.90 * £13.90

In stock

Caliber: 270/6.8 mm (.277) Product no.: 749000772

In stock

12.9 GBP 8 £12.90 * £13.90

-8 %

Accurately measure your rifle's chamber length with the Sinclair Chamber Length Gauge, ensuring optimal case trimming and preventing over-trimming by .030 inch or more.

Sinclair Chamber Length Gage - CHAMBER LENGTH GAUGE, 32 CALIBER

11.9 GBP 2 £11.90 * £12.90

In stock

Caliber: 32 Caliber (.312-.313) Product no.: 749011493

In stock

11.9 GBP 2 £11.90 * £12.90

-13 %

Accurately measure your rifle's chamber length with the Sinclair Chamber Length Gage, ensuring optimal case trimming and preventing over-trimming for precise reloads.

Sinclair Chamber Length Gage - CHAMBER LENGTH GAUGE, 338 CALIBER

13.9 GBP 5 £13.90 * £15.90

In stock

Caliber: 338 Caliber (.338) Product no.: 749000752

In stock

13.9 GBP 5 £13.90 * £15.90

-8 %

The Sinclair Chamber Length Gage accurately measures your rifle's chamber length, ensuring optimal case trimming and preventing over-trimming for precise handloading.

Sinclair Chamber Length Gage - CHAMBER LENGTH GAUGE, 35 CALIBER

11.9 GBP 2 £11.90 * £12.90

In stock

Caliber: 35 Caliber (.358) Product no.: 749011494

In stock

11.9 GBP 2 £11.90 * £12.90

-8 %

The Sinclair Chamber Length Gauge ensures accurate chamber measurements, preventing over-trimming and enhancing your reloading precision with durable, repeatable use.

Sinclair Chamber Length Gage - CHAMBER LENGTH GAUGE, 375 CALIBER

11.9 GBP 2 £11.90 * £12.90

In stock

Caliber: 375 Caliber (.375) Product no.: 749011495

In stock

11.9 GBP 2 £11.90 * £12.90

-8 %

Sinclair Chamber Length Gage - CHAMBER LENGTH GAUGE, 408 CALIBER

11.9 GBP 24 £11.90 * £12.90

In stock

Caliber: 408 Cheytec (.408) Product no.: 749011497

In stock

11.9 GBP 24 £11.90 * £12.90

-13 %

Accurately measure your rifle's chamber length with the Sinclair Chamber Length Gauge, ensuring optimal case trimming for consistent reloading results.

Sinclair Chamber Length Gage - CHAMBER LENGTH GAUGE, 416 CALIBER

13.9 GBP 1 £13.90 * £15.90

In stock

Caliber: 416 Caliber (.416) Product no.: 749011498

In stock

13.9 GBP 1 £13.90 * £15.90

-8 %

Measure your rifle's chamber length accurately with the Sinclair Chamber Length Gage, ensuring optimal case trimming and preventing over-trimming by .030 inch or more.

Sinclair Chamber Length Gage - CHAMBER LENGTH GAUGE, 44 CALIBER

11.9 GBP 1 £11.90 * £12.90

In stock

Caliber: 44 Caliber (.429-.430) Product no.: 749011499

In stock

11.9 GBP 1 £11.90 * £12.90

-8 %

The Sinclair Chamber Length Gage accurately measures your rifle's chamber length, preventing over-trimming and ensuring optimal case fit for reloading.

Sinclair Chamber Length Gage - CHAMBER LENGTH GAUGE, 45 CALIBER

11.9 GBP 1 £11.90 * £12.90

In stock

Caliber: 45 Caliber (.451-.454) Product no.: 749011500

In stock

11.9 GBP 1 £11.90 * £12.90

-9 %

The Sinclair Chamber Length Gage allows precise measurement of your rifle's chamber length, ensuring optimal case trimming for improved accuracy and performance.

Sinclair Chamber Length Gage - CHAMBER LENGTH GAUGE, 50 CALIBER

9.9 GBP 2 £9.90 * £10.90

In stock

Caliber: 50 Caliber (.510) Product no.: 749011501

In stock

9.9 GBP 2 £9.90 * £10.90

-7 %

Accurately measure your rifle's chamber length with the Sinclair Chamber Length Gauge, ensuring precise case trimming and optimal reloading performance.

Sinclair Chamber Length Gage - CHAMBER LENGTH GAUGE, 6MM

12.9 GBP 28 £12.90 * £13.90

In stock

Caliber: 243/6 mm (.243) Product no.: 749000796

In stock

12.9 GBP 28 £12.90 * £13.90

-13 %

Accurately measure your rifle's chamber length with the Sinclair Chamber Length Gage, ensuring optimal case trimming and enhancing reloading precision.

Sinclair Chamber Length Gage - CHAMBER LENGTH GAUGE, 6.5MM

13.9 GBP 25 £13.90 * £15.90

In stock

Caliber: 264/6.5 mm (.264) Product no.: 749000783

In stock

13.9 GBP 25 £13.90 * £15.90

-8 %

Accurately measure your rifle's chamber length with the Sinclair Chamber Length Gage, ensuring precise case trimming and optimal performance for handloaders.

Sinclair Chamber Length Gage - CHAMBER LENGTH GAUGE, TIGHT NECK, 6MM

11.9 GBP 2 £11.90 * £12.90

In stock

Caliber: 243/6 mm (.243) Product no.: 749000751

In stock

11.9 GBP 2 £11.90 * £12.90

-13 %

Accurately measure your rifle's chamber length with the Sinclair Chamber Length Gauge, ensuring optimal case trimming for precise reloading.

Sinclair Chamber Length Gage - CHAMBER LENGTH GAUGE, 7MM

13.9 GBP 8 £13.90 * £15.90

In stock

Caliber: 284/7 mm (.284) Product no.: 749000784

In stock

13.9 GBP 8 £13.90 * £15.90

The Sinclair Chamber Length Gage accurately measures your rifle's chamber length, ensuring proper case trimming and preventing over-trimming for optimal performance.

Sinclair Chamber Length Gage - 404 JEFFERY CHAMBER LENGTH GAGE

Not available

Caliber: 404 Jeffery (.422-.423) Product no.: 749011496

Not available

7.9 GBP 0 £7.90 *

Accurately measure your rifle's chamber length with the Sinclair Chamber Length Gage, ensuring precise case trimming and enhanced reloading efficiency.

Sinclair Chamber Length Gage - 9.3MM CHAMBER LENGTH GAGE

Not available

Caliber: 9.3 mm (.366) Product no.: 749011503

Not available

8.9 GBP 0 £8.90 *

9.9 13.9 21 GBP

-7 %

MSRP £13.90

12.9 GBP £12.90

Prices inclusive of duty & VAT.

Product no.: 749000804

Mfr. No.: G308

The Sinclair Chamber Length Gauges are designed so the handloader can determine the true length of his rifle's chamber when measuring from the bolt face to the end of the chamber's neck. This measurement will tell you how much excess case length your chamber may have over published trim lengths in reloading handbooks. The Sinclair Gauges are inserted into a fired, unprimed shortened case and then chambered into your rifle. The insert pushes back into the case when it contacts the end of your chamber. You then extract the case and measure the overall length. The gauge is made of 12L14 soft steel so it will not damage your chamber. Step-by-step instructions accompany each gauge. The gauges can be used over and over again. The differences between published trim lengths and the actual length of your chamber can be quite significant. You could be over trimming your cases by .030 inch or more. NOTE: The 22 caliber gauge will not work on thin-necked cases such as the 22 Hornet, 218 Bee, or cartridges based on these cases. The 30 caliber gauge will not work on teh 30-30 Winchester. None of the gauges listed will work on tight-necked chambers except for the G-243T. Should not be used in handguns, semi automatic rifles, lever actions rifles and pump action rifles.

In stock More than 10 pieces in USA warehouse

10+

-7 %

MSRP £13.90

£12.90

Prices inclusive of duty & VAT.

10+

Delivery time approx. 7-14 days.

100-Day Return Policy

Delivery time approx. 7-14 days.

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.

Accurate chamber length measurement
Durable 12L14 soft steel
Reusable for multiple measurements

Wish List Ask question

9.9 13.9 21 GBP

Description Specification Customers reviews Accessories

SINCLAIR INTERNATIONAL CHAMBER LENGTH GAUGE, 30 CALIBER

-7 %

MSRP £13.90

12.9 GBP £12.90

Prices inclusive of duty & VAT.

10+

-7 %

MSRP £13.90

£12.90

Prices inclusive of duty & VAT.

10+

Delivery time approx. 7-14 days.

100-Day Return Policy

Description:

Accurately measure your rifle's chamber length with ease!

The Sinclair Chamber Length Gage from SINCLAIR INTERNATIONAL is an essential tool for handloaders looking to determine the true length of their rifle's chamber. By measuring from the bolt face to the end of the chamber's neck, this gauge provides critical information about excess case length compared to published trim lengths found in reloading handbooks.

Key Features:

Designed for accurate measurement of chamber length
Constructed from durable 12L14 soft steel to prevent chamber damage
Step-by-step instructions included for user convenience
Reusable design for multiple measurements

The Sinclair Gauges are easily inserted into a fired, unprimed shortened case and chambered into your rifle. As the insert contacts the end of your chamber, it pushes back into the case, allowing you to extract the case and measure the overall length accurately. This process can reveal significant differences between published trim lengths and the actual length of your chamber, potentially indicating that you may be over-trimming your cases by .030 inch or more.

Important Notes:

The 22 caliber gauge is not suitable for thin-necked cases such as the 22 Hornet, 218 Bee, or cartridges based on these cases.
The 30 caliber gauge is not compatible with the 30-30 Winchester.
None of the gauges listed will work on tight-necked chambers except for the G-243T.
Not intended for use in handguns, semi-automatic rifles, lever action rifles, or pump action rifles.

Enhance your reloading accuracy with the Sinclair Chamber Length Gage, available now at Brownells UK!

Attributes

Caliber:
```
30 Caliber (.308)
```
Delivery weight: 0.032kg
Shipping width: 102mm
Shipping length: 76mm

Item details

Made in USA

Customers reviews

Customer ratings (10)

3.4 / 5

Definitely recommended

5.56 NATO gaged Chamber length new DPMS 10/09/2016

Followed instructions as provided and measured the chamber 3 times and the length came out exactly 1.781 on the chamber. Knowing this I will size all my Lake City brass to 1.771. Which is where the vast major of measures to any way. Now I have confidence in my reloads thanks to this marvelous little cheap gage. I will keep all my brass separate and will use the 1.771 brass for match shooting and everything else for plinking.

Definitely recommended

Worked great 24/12/2015

I had no trouble making a case to accept this gauge. I'm not sure why so many reviewers had difficulties. To make this easier for you gents, trim a re-sized case to 1.640 then insert the gauge. Yes, the case looks short and only has a little bit of neck left, but it works great!

One thing I would change about the directions....it says to drill out the flash hole to make access to push the gauge back out. This is not needed. I used a kinetic bullet puller to "lengthen/re-set" the case with gauge installed. It only needs to be lengthened by 10 thou between uses.

Not recommended

This is the eigth one I've bought 12/04/2011

Since this was the 8th one I've bought, I thought I knew what to expect . The other 7 are shiny and well machined. This one looks like it was cast (black & not very smooth). The first one I was sent (this time), had a smaller size diameter close to the head then down by the tip. It would push in with the appropriate tension until it got to the undersized section ,then just flop in and out about .0685". The replacement I was sent (thank you) had a uniform shank.It, however still looked like an unfinished tool. I started the "tool" in my shortened case ,chambered it in my gun, and discovered I couldn't close the bolt all the way. I took another .01 off the case--still no luck.I measured the case and "tool" length and found it to be 2.075" . That's .03" longer then my Sierra manual lists the chamber should be. I couldn't take anymore off the case ,and still have a neck , so I took another look at the "tool". The other 7 (that all work perfectly)have a head on them that runs from .085" on the .204 to about .098" on the .30cal. . This G-243 has a head that measures .1405". After chucking it up and facing it down to .09" , I could finally measure the rifle's chamber (2.065").I thought [$] was cheaper then setting up a machine and making my own. Not in this case! I don't have any of this fancy leaded steel , and I think [$] is a pretty high price for this size piece for me to machine. So, if and when I need a 9th caliber gage, I have some brass round stock that will probably turn down just fine.

Variations:

-7 %

Sinclair Chamber Length Gage - CHAMBER LENGTH GAUGE, 30 CALIBER

12.9 GBP 21 £12.90 * £13.90

In stock

Caliber: 30 Caliber (.308) Product no.: 749000804

In stock

12.9 GBP 21 £12.90 * £13.90

-9 %

Sinclair Chamber Length Gage - CHAMBER LENGTH GAUGE, 17 CALIBER

9.9 GBP 1 £9.90 * £10.90

In stock

Caliber: 17 Caliber (.172) Product no.: 749000746

In stock

9.9 GBP 1 £9.90 * £10.90

-7 %

Sinclair Chamber Length Gage - CHAMBER LENGTH GAUGE, 20 CALIBER

12.9 GBP 1 £12.90 * £13.90

In stock

Caliber: 20 Caliber (.204) Product no.: 749000795

In stock

12.9 GBP 1 £12.90 * £13.90

-8 %

Sinclair Chamber Length Gage - CHAMBER LENGTH GAUGE, 22 CALIBER

11.9 GBP 21 £11.90 * £12.90

In stock

Caliber: 22 Caliber (.223-.224) Product no.: 749000811

In stock

11.9 GBP 21 £11.90 * £12.90

-7 %

Sinclair Chamber Length Gage - CHAMBER LENGTH GAUGE, 25 CALIBER

12.9 GBP 1 £12.90 * £13.90

In stock

Caliber: 25 Caliber (.257) Product no.: 749000771

In stock

12.9 GBP 1 £12.90 * £13.90

-7 %

Sinclair Chamber Length Gage - CHAMBER LENGTH GAUGE, 270 CALIBER

12.9 GBP 8 £12.90 * £13.90

In stock

Caliber: 270/6.8 mm (.277) Product no.: 749000772

In stock

12.9 GBP 8 £12.90 * £13.90

-8 %

Sinclair Chamber Length Gage - CHAMBER LENGTH GAUGE, 32 CALIBER

11.9 GBP 2 £11.90 * £12.90

In stock

Caliber: 32 Caliber (.312-.313) Product no.: 749011493

In stock

11.9 GBP 2 £11.90 * £12.90

-13 %

Sinclair Chamber Length Gage - CHAMBER LENGTH GAUGE, 338 CALIBER

13.9 GBP 5 £13.90 * £15.90

In stock

Caliber: 338 Caliber (.338) Product no.: 749000752

In stock

13.9 GBP 5 £13.90 * £15.90

-8 %

Sinclair Chamber Length Gage - CHAMBER LENGTH GAUGE, 35 CALIBER

11.9 GBP 2 £11.90 * £12.90

In stock

Caliber: 35 Caliber (.358) Product no.: 749011494

In stock

11.9 GBP 2 £11.90 * £12.90

-8 %

Sinclair Chamber Length Gage - CHAMBER LENGTH GAUGE, 375 CALIBER

11.9 GBP 2 £11.90 * £12.90

In stock

Caliber: 375 Caliber (.375) Product no.: 749011495

In stock

11.9 GBP 2 £11.90 * £12.90

-8 %

Sinclair Chamber Length Gage - CHAMBER LENGTH GAUGE, 408 CALIBER

11.9 GBP 24 £11.90 * £12.90

In stock

Caliber: 408 Cheytec (.408) Product no.: 749011497

In stock

11.9 GBP 24 £11.90 * £12.90

-13 %

Sinclair Chamber Length Gage - CHAMBER LENGTH GAUGE, 416 CALIBER

13.9 GBP 1 £13.90 * £15.90

In stock

Caliber: 416 Caliber (.416) Product no.: 749011498

In stock

13.9 GBP 1 £13.90 * £15.90

-8 %

Sinclair Chamber Length Gage - CHAMBER LENGTH GAUGE, 44 CALIBER

11.9 GBP 1 £11.90 * £12.90

In stock

Caliber: 44 Caliber (.429-.430) Product no.: 749011499

In stock

11.9 GBP 1 £11.90 * £12.90

-8 %

Sinclair Chamber Length Gage - CHAMBER LENGTH GAUGE, 45 CALIBER

11.9 GBP 1 £11.90 * £12.90

In stock

Caliber: 45 Caliber (.451-.454) Product no.: 749011500

In stock

11.9 GBP 1 £11.90 * £12.90

-9 %

Sinclair Chamber Length Gage - CHAMBER LENGTH GAUGE, 50 CALIBER

9.9 GBP 2 £9.90 * £10.90

In stock

Caliber: 50 Caliber (.510) Product no.: 749011501

In stock

9.9 GBP 2 £9.90 * £10.90

-7 %

Sinclair Chamber Length Gage - CHAMBER LENGTH GAUGE, 6MM

12.9 GBP 28 £12.90 * £13.90

In stock

Caliber: 243/6 mm (.243) Product no.: 749000796

In stock

12.9 GBP 28 £12.90 * £13.90

-13 %

Sinclair Chamber Length Gage - CHAMBER LENGTH GAUGE, 6.5MM

13.9 GBP 25 £13.90 * £15.90

In stock

Caliber: 264/6.5 mm (.264) Product no.: 749000783

In stock

13.9 GBP 25 £13.90 * £15.90

-8 %

Sinclair Chamber Length Gage - CHAMBER LENGTH GAUGE, TIGHT NECK, 6MM

11.9 GBP 2 £11.90 * £12.90

In stock

Caliber: 243/6 mm (.243) Product no.: 749000751

In stock

11.9 GBP 2 £11.90 * £12.90

-13 %

Sinclair Chamber Length Gage - CHAMBER LENGTH GAUGE, 7MM

13.9 GBP 8 £13.90 * £15.90

In stock

Caliber: 284/7 mm (.284) Product no.: 749000784

In stock

13.9 GBP 8 £13.90 * £15.90

Sinclair Chamber Length Gage - 404 JEFFERY CHAMBER LENGTH GAGE

Not available

Caliber: 404 Jeffery (.422-.423) Product no.: 749011496

Not available

7.9 GBP 0 £7.90 *

Sinclair Chamber Length Gage - 9.3MM CHAMBER LENGTH GAGE

Not available

Caliber: 9.3 mm (.366) Product no.: 749011503

Not available

8.9 GBP 0 £8.90 *

Customers also bought

-12 %

-13 %

+ 15 variants

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

SINCLAIR INTERNATIONAL

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

Case Gauges & Headspace Tools

3.1

In stock

£16.90

£14.90 £13.90 - 16.90

(Select Items on Sale!)

-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

In stock

£10.90

£9.90 £9.90 - 12.90

(Select Items on Sale!)

-9 %

-10 %

+ 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

In stock

£21.90

£19.90 £18.90 - 20.90

(Select Items on Sale!)

-8 %

-13 %

+ 3 variants

The Sinclair Bullet Sorting Stand with Dial Indicator offers precise sorting of bullets, ensuring consistency and accuracy for optimal shooting performance.

SINCLAIR INTERNATIONAL

BULLET SORTING STAND WITH DIAL INDICATOR
BULLET SORTING STAND

Bullet Comparators

3.7

In stock

£119.90

£109.90 £69.90 - 169.90

(Select Items on Sale!)

Oops! Something went wrong.

We encountered an error while loading this content. Please refresh the page to continue. If the issue persists, contact our customer support.

Site Navigation

Product Categories

Ordering

Customer Service

Connect

Secure payment methods

Trade Associations

Welcome!

to Brownells UK, your destination for anything gun related. With our roots in a genuine passion for firearms, we bring you an unmatched selection of Gun Parts, Firearm Accessories, Gunsmithing Tools, Scopes & Red Dot Sights and Expert Knowledge.

Whether you're looking to maintain, repair, or upgrade, we've got what you need!

For Shooters, By Shooters
We share your enthusiasm and know exactly what you're looking for because we're part of the community.

Massive Selection
From the essentials to the unique, find everything under one roof.

Our blend of tradition and innovation
Shop with the convenience of modern technology, backed by a legacy of experience.

Browse our collection and discover why we're the trusted name in shooting sports & hunting.