Sinclair Bump Gage Inserts are used to measure the amount of shoulder bump when setting up full length sizing dies. Our Bump Gages install in either of our comparator bodies and are machined to fit particular shoulder angles of cartridges. Rather than measuring to the datum line, these gages indicate off of the shoulder of the case to get a better, more easily assessable measurement of how much you are actually sizing your cases. We usually recommend between .001" to .002" bump for bolt action rifles and between .003" and .005" for AR-15 type rifles. Also a useful tool for keeping your brass and loaded ammunition separated if you have multiple rifles chambered for the same cartridge and checking loaded ammunition.
Sinclair Bump Gage Insert, Standard Magnums up to 30 Cal,25\
Attributes
Cartridge:300 Winchester Magnum,6.5 x 55 mm Swedish Mauser,225 Winchester,30 Remington AR,7 mm STW,264 Winchester Magnum,8 mm Remington Mag,7 mm Remington Magnum,338 Winchester Magnum
Delivery weight:0.023kg
Shipping width:83mm
Shipping length:146mm
UPC:050806111325
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.
Not recommended
Poor / Inaccurate Description 03/03/2018
Does NOT fit 300 Blackout without modification.
Not recommended
Incorrect fitment 24/02/2018
The details on this part say this fits 300 Blackout. Turns out it doesn't unless you modify it does not explain that anywhere in the description.
Slightly recommend
Feels Like Plastic 26/01/2017
I thought the product was made of metal, which is should be. Feels like plastic, which it should not be. I didn't have much luck with this product and the inserts using it as a bump gauge. The readings were inconsistent even with two different calipers. Even trying to bump .308 cases back 4/1000ths for an AR10 was nearly impossible to do with any consistency. The finished products did not shoot as well as a fully resized cases in the testing I did.
Not recommended
Only works with certain calipers 13/12/2016
We use Aero Space brand calipers at the EPA. The slot on these arent wide enough to fit over them. That's OK but Sinclair should list some models they work with OR the width of the slot.
Definitely recommended
Quality Construction 18/07/2016
The bump gauge/comparator body has quality construction, and hold the inserts well. They attach to my calipers securely, and work well.
Definitely recommended
great product 01/03/2016
I really like the insert it's made of Stainless Steel so it will not wear easy . The gauge is also very easy to use, works on my Hornady body too.
Not recommended
Does not work for .416 Rigby 25/01/2015
The .416 Rigby is a beltless cartridge that headspaces on its ample 45 degree shoulder. This bump gage hole diameter is too small to host the outside dimensions of the .416 Rigby brass. It would have been nice to know there was a size limit on the exterior brass dimensions so as to avoid a return.
Definitely recommended
These Fit the Hornady Tools 07/01/2015
This little item told me right away what problem My sons hand loads had very easy to use and the fact they fit the Hornady tools that look like this is a big plus....If you already have the Hornady gauges.
Slightly recommend
Requires honing geometry change 24/01/2014
The tapered opening is right at .277 and goes extremely far down VLD type/Accubond bullets, this makes it impossible to measure Ogive Combined Overall Length on loaded bullets. The older stainless steel hexagonal shaped comparator is much more useful as it's tapered opening is at .268". This comparator insert's tapered opening should start at .270" within .001" of that.
Definitely recommended
Great tool for measuring shoulder bump 13/12/2013
I bought this tool to use with the Sinclair XL Comparator body and it works great! I am able to measure the distance between the should and the base of a fire cartridge and then set my sizing die to bump the shoulder back a certain distance. I would definitely buy this tool again.
Definitely recommended
Great tool for measuring bullets/cases 13/12/2013
I bought this tool in order to measure bullets from the ojive to the base and also to measure should bump. It's a high quality tool and works perfectly for my needs. Being that it's the XL version, you're able to measure shoulders with a bullets installed.
Not recommended
Poor discription 02/07/2012
It's listed as "30-06 Family" but will not work with 17deg shoulders over 338 cal.
Definitely recommended
Much Better than Hornady LNL inserts 23/02/2011
It's much easier to measure headspace with an insert that's tapered to match the cartridge's shoulder angle. Easier to use than the 90 deg. edge of the straight hole drilled in the original Hornady LNL inserts.
Definitely recommended
Keep it simple 09/02/2011
Simplicity is more often than not the best way to do things...This product is so simple but is something every shooter should have at their reloading bench. Use it every few hundred rounds to make sure your desired bullet jump matches wear in barrel.
Get precise measurements with the Sinclair Bump Gage Insert 🔧, designed for Standard Magnums up to 30 Cal. Perfect for accuracy!
The Sinclair Bullet Comparator Inserts are designed for use with the Sinclair Comparator and Bump Gage Body to accurately measure bullet ogive-to-base and loaded round measurements.
These inserts are crafted from stainless steel with a taper and a short straight section to replicate the chamber throat more precisely, reducing wobble and increasing consistency.
They provide a more reliable measurement than overall length by focusing on the ogive, which is less variable than the meplat (bullet tip).
The Sinclair Chamber Length Gauge allows handloaders to measure the true chamber length from the bolt face to the chamber's neck end, revealing potential excess case length over published trim lengths.
Made of 12L14 soft steel, the gauge is designed to avoid damaging the chamber and comes with step-by-step instructions, suitable for repeated use.
Compatibility restrictions include the 22 caliber gauge not working on thin-necked cases like the 22 Hornet and 218 Bee, and the 30 caliber gauge not fitting the 30-30 Winchester.
The Sinclair TiN Expander Mandrels offer increased abrasion resistance and lubricity over standard steel mandrels due to the Titanium Nitride coating.
These mandrels are specifically designed to be 0.001" under bullet diameter for expanding the necks of brass prior to neck turning and setting neck tension.
The 17 Caliber TiN Expander Mandrel has a diameter of 0.171 inches and is a product of SINCLAIR INTERNATIONAL, suitable for those not requiring the upgrade to Carbide Mandrels.