$10.99
39 in stock
Online inventory may differ from in-store availability.
Quick turnaround so you get your gear sooner.
Trusted checkout with industry-standard protection.
Keeping Traditions Alive Since 1953
Secure Transactions provided with 
If you handload the 223 Remington family and want tighter control over how far you're pushing the shoulder back, this Sinclair #23 bump gage insert is the piece that makes it happen. It's machined for a 23 degree shoulder angle, which covers 223 Remington, 5.56mm NATO, 17 Remington, 221 Remington Fireball, 222 Remington, and 222 Remington Magnum. The insert drops into a Sinclair comparator body and gives you a clean, repeatable reference point for measuring shoulder bump.
Unlike a go/no-go gage that reads off the datum line, these inserts indicate off the actual shoulder of the case. That means you're measuring the real change between a fired case and a sized one, which is exactly what you want when fine tuning a full length die. Many reloaders aim for around .001 to .002 inch of bump for bolt guns and a touch more, in the .003 to .005 inch range, for AR-15 pattern rifles to keep feeding reliable.
The insert is machined from stainless steel with a taper that duplicates the shoulder of your brass, which cuts out the wobble you get from a plain drilled hole. You secure it in a comparator body with a 5/64 hex wrench, clamp the body to one blade of your calipers, zero out, and start measuring from the case head to the shoulder. It plays nicely with the standard Sinclair comparator body as well as current Hornady comparator bodies, though note that keeping measurements consistent matters more than matching another brand's exact readout.
Minimally sizing your brass stretches case life and helps keep your loads consistent round to round, and this little insert is the measuring half of that equation. It's a simple, well made tool that earns its keep every time you set up a sizing die for the 223 family. Pair it with a comparator body and a decent set of calipers and you've got everything you need to bump shoulders with purpose instead of guesswork.
The #23 insert is machined for cartridges with a 23 degree shoulder in the 223 Remington family. That includes 223 Remington, 5.56mm NATO, 17 Remington, 221 Remington Fireball, 222 Remington, and 222 Remington Magnum. One insert handles the whole group since they share that shoulder angle.
Yes. The bump gage insert is just the insert and has to be installed into a comparator body that clamps onto your caliper blade. It fits the Sinclair comparator body and current Hornady comparator bodies, and you secure it with a 5/64 hex wrench.
A go/no-go gage reads off the SAAMI datum line to tell you pass or fail. This insert indicates off the actual shoulder of the case so you can measure the change between a fired case and a sized one. It's about tracking how much you're bumping the shoulder, not checking against a fixed standard.
A common starting point is about .001 to .002 inch of bump for bolt action rifles, which keeps brass life long and chambering smooth. For AR-15 pattern rifles, many reloaders go a little more, in the .003 to .005 inch range, to make sure rounds feed and chamber reliably. The insert lets you measure and dial that in precisely.
| UPC | 050806111202 |
|---|---|
| Manufacturer |
You must be logged in to post a review.
Reviews
There are no reviews yet.