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

-7 %

SINCLAIR INTERNATIONAL CHAMBER LENGTH GAUGE, 270 CALIBER

749000772

Variations

Filters:

Variations:

-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 9 £12.90 * £13.90

In stock

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

In stock

12.9 GBP 9 £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

-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 5 £12.90 * £13.90

In stock

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

In stock

12.9 GBP 5 £12.90 * £13.90

-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 26 £12.90 * £13.90

In stock

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

In stock

12.9 GBP 26 £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 3 £13.90 * £15.90

In stock

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

In stock

13.9 GBP 3 £13.90 * £15.90

-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 %

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

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 9 £12.90 * £13.90

In stock

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

In stock

12.9 GBP 9 £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 29 £13.90 * £15.90

In stock

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

In stock

13.9 GBP 29 £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 3 £11.90 * £12.90

In stock

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

In stock

11.9 GBP 3 £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 10 £13.90 * £15.90

In stock

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

In stock

13.9 GBP 10 £13.90 * £15.90

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

12.9 GBP 0 £12.90 *

Backorderable

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

Backorderable

12.9 GBP 0 £12.90 *

Sinclair Chamber Length Gage - CHAMBER LENGTH GAUGE, 35 CALIBER

12.9 GBP 0 £12.90 *

Backorderable

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

Backorderable

12.9 GBP 0 £12.90 *

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.: 749000772

Mfr. No.: G277

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 9 pcs. in the 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

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9.9 13.9 21 GBP

Description Specification Customers reviews Accessories

SINCLAIR INTERNATIONAL CHAMBER LENGTH GAUGE, 270 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 Chamber Length with the Sinclair Chamber Length Gage

The Sinclair Chamber Length Gauges are expertly designed for handloaders to determine the precise length of their rifle's chamber. By measuring from the bolt face to the end of the chamber's neck, you can assess how much excess case length your chamber may have over the published trim lengths found in reloading handbooks.

Key Features:

Insert the gauge into a fired, unprimed shortened case, then chamber it into your rifle.
The insert will push back into the case upon contacting the end of your chamber.
Extract the case and measure the overall length for accurate readings.
Constructed from 12L14 soft steel, ensuring no damage to your chamber.
Includes step-by-step instructions with each gauge.
Reusable for multiple measurements.

The difference between the published trim lengths and the actual length of your chamber can be substantial, with potential over-trimming of 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 listed gauges will work on tight-necked chambers, except for the G-243T.
Should not be used in handguns, semi-automatic rifles, lever-action rifles, or pump-action rifles.

Ensure your reloading process is precise and efficient with the Sinclair Chamber Length Gage, available now at Brownells UK.

Top takeaways

The Sinclair Chamber Length Gauge allows handloaders to accurately measure their rifle's chamber length from the bolt face to the end of the chamber's neck.
Made of 12L14 soft steel, the gauge won't damage the chamber and comes with instructions for repeated use to prevent over-trimming of cases.
It is not suitable for use with thin-necked cases like the 22 Hornet or tight-necked chambers, except for the G-243T, and should not be used in handguns or certain rifles.

Attributes

Caliber:
```
270/6.8 mm (.277)
```
Delivery weight: 0.032kg
Shipping height: 1mm
Shipping width: 102mm
Shipping length: 152mm

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, 270 CALIBER

12.9 GBP 9 £12.90 * £13.90

In stock

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

In stock

12.9 GBP 9 £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

-7 %

Sinclair Chamber Length Gage - CHAMBER LENGTH GAUGE, 25 CALIBER

12.9 GBP 5 £12.90 * £13.90

In stock

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

In stock

12.9 GBP 5 £12.90 * £13.90

-7 %

Sinclair Chamber Length Gage - CHAMBER LENGTH GAUGE, 30 CALIBER

12.9 GBP 26 £12.90 * £13.90

In stock

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

In stock

12.9 GBP 26 £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 3 £13.90 * £15.90

In stock

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

In stock

13.9 GBP 3 £13.90 * £15.90

-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 9 £12.90 * £13.90

In stock

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

In stock

12.9 GBP 9 £12.90 * £13.90

-13 %

Sinclair Chamber Length Gage - CHAMBER LENGTH GAUGE, 6.5MM

13.9 GBP 29 £13.90 * £15.90

In stock

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

In stock

13.9 GBP 29 £13.90 * £15.90

-8 %

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

11.9 GBP 3 £11.90 * £12.90

In stock

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

In stock

11.9 GBP 3 £11.90 * £12.90

-13 %

Sinclair Chamber Length Gage - CHAMBER LENGTH GAUGE, 7MM

13.9 GBP 10 £13.90 * £15.90

In stock

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

In stock

13.9 GBP 10 £13.90 * £15.90

Sinclair Chamber Length Gage - CHAMBER LENGTH GAUGE, 22 CALIBER

12.9 GBP 0 £12.90 *

Backorderable

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

Backorderable

12.9 GBP 0 £12.90 *

Sinclair Chamber Length Gage - CHAMBER LENGTH GAUGE, 35 CALIBER

12.9 GBP 0 £12.90 *

Backorderable

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

Backorderable

12.9 GBP 0 £12.90 *

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 *

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