Redding’s Instant Indicator-Headspace And Bullet Comparator
Reviewed by Technical Editor
The Redding Instant Indicator is a bit like a Swiss Army Knife in that it can perform quite a few tasks. It’s a very useful tool for precision reloading but, as you would imagine with a big dial sitting on top of what looks like a reloading die, it is also all about measuring cases, bullets and ammunition. It comes with three inserts that allow you to perform the following measurements.
Die Setup and Headspace
One of the first parts of the reloading process is setting your dies up to suit the chamber in your rifle. We want to set the sizing die up to make sure we size the case just enough for reliable feeding in our rifle. In a bolt-action weapon we want the critical shoulder area pushed back only enough to allow you to close the bolt; this will be somewhere between zero and 4 thousandths of an inch, depending on the rifle.
The Instant Indicator makes this easy. Set it up as per the instructions and zero it, using the setup gauge-which is the same dimension as a Sporting Arms and Manufacturers’ Institute specification minimum chamber size (SAAMI). Then replace the setup gauge and use a case that has been fired in your rifle to get an indication of how close you are to having a minimum-spec chamber. Record this setting, or zero it, so you can use it as a reference point.
Now while it is nice to see the difference between your chamber and a SAAMI minimum spec chamber, what’s most important is how we can use this measurement to set up our resizing die so that we only size the brass enough for reliable feeding. Start by fully raising the ram on the press, remembering that some presses cam-over and reduce the ram height fractionally as the handle is fully lowered. Next, screw your full-length resizing die into the press until it touches the shell holder. In most cases this is how you would set your die up to fully resize your case.
Now we need to unscrew the die half a turn, insert a lubricated case, resize it, and use the Instant Indicator to see how much the case has been sized down. We continue screwing the die down a sixteenth of a turn at a time until we reach the desired measurement. I set up some cases that were fired in the Rod & Rifle Remington 5R in order to compare them to a fully-resized case and the reading from the setup gauge.
It is important to note that the cases should be fired at least twice in the rifle to make sure that have expanded to fully reflect the chamber dimensions. The 5R brass measured 5 thousandths more at the shoulder than the minimum-spec chamber as per the setup gauge.
I then checked a case that had been resized with the resizing die set up to touch the shell-holder; the Instant Indicator showed zero. This means that the Redding resizing die, when set up to touch the shell-holder, resizes a case to the SAAMI minimum specifications, which allow for a 10 thousandths of an inch variance between minimum and maximum dimensions; in this case the Remington chamber is right in the middle. Now, 5 thousandths is not a lot of room but it is more than we need. I wanted to preserve my brass by not overworking it while at the same time having ammunition that chambers easily; so I decided to set the shoulder back 2 thousandths of an inch. Bearing in mind that brass springs back after firing, the fired brass will be 1 or 2 thousandths smaller than the chamber, so my setting will allow the case 3 - 4 thousandths headspace; plenty for easy chambering. If I had set it with the die touching the shell holder I would have had 6 or 7 thousandths of an inch headspace, much more than is necessary. If I were loading for a competition rifle I would probably set it for zero and know I may have a crush fit.
The Instant Indicator is also great for checking the length of your brass. Brass stretches and flows after repeated firings and sometimes will lengthen significantly after even one firing. Checking brass is something I do more regularly now because it’s so easy with the Instant Indicator. All that is necessary is to remove the shoulder contactor and replace it with the sliding blank contactor.
The reason we check case length is for safety; when a case gets too long the end of the case can come into contact with the end of the chamber. If this happens you may be lucky and find you have difficulty closing your bolt, but if you do manage to close it you will have pushed the case into the taper that leads to the throat. This can increase the pressure in your chamber, leading to possible blown primers, case failure or firearm damage. Worst of all you can put yourself at risk here. Take a case that has been trimmed to the maximum length, for the .308 this is 2.015 of an inch. Put the case in the shell holder, raise the ram and set your indicator to zero; when you check your cases they will give you a reading above or below zero. Anything above zero should be trimmed back to 2.005.
Bullet seating depth
The Instant Indicator also allows you to check your bullet seating depth. Bullet seating depth has a big influence on accuracy, as well as your velocity, speed and spread. (It’s a subject in itself though, so I will cover it in more detail in an upcoming issue of Rod & Rifle.) Traditional wisdom says that seating the bullet out to touch or be close to the rifling will tighten accuracy - but this is not always the case, and multiple depths should be tried. You must also make sure that if a bullet is seated out to be close to the rifling it will still fit in the magazine. The Instant Indicator makes these measurements quickly and accurately and because it measures off the ogive of the bullet rather than the tip it gives a better indication of the actual seating depth. This is because some bullets - hollow-points especially - can vary in overall length, giving a false reading. Measuring at the ogive is always the most reliable way of getting a correct reading. It also makes it easier to setup other projectiles as the ogive dimension is essentially the same for bullets of the same calibre.
The Instant Indicator is a very handy tool for the precision hand loader; swapping the internal components to take various measurements is simple and the big clear dial means you’ll find it hard to make a mistake by misreading it. The Instant Indicator is versatile, very fast and easy to use, and the supplied instructions are good and clear.
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