Redding Comparater

Poconolg

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Has anyone used the Redding Comparater to compare length of shells and base of a cartridge to point of contact to the lands?
 
Has anyone used the Redding Comparator

No I haven't:

http://www.midwayusa.com/Product/173320/redding-instant-indicator-comparator-with-dial-223-remington

The Redding Instant Indicator Comparator with Dial is useful for quickly comparing headspace and bullet seating depths within 0.001 of an inch. The headspace measurement is from the case shoulder to the base.

It did not take them long to break into the 'the case has head space' routine. I off set the length of the chamber with the length of the case. $129.00:eek:

F. Guffey
 
Rant deleted. Daddy told me never to p*ss into the wind. I forgot that for a moment. May the dead horse live long and prosper. :)
 
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So this comparator gives us a gage to measure that is in the SAM spec.? Since the chambers can be loose of tight we still need to know what the chamber is to spec. I suspect a fired case would be ground (0).

The nice thing about forums is if you don't want to read it you can move on.
 
The nice thing about forums is if you don't want to read it you can move on.

Longshot4,

I suspect a fired case would be ground (0).

That would be a good start, another start would be to measure the length of the case from the shoulder to the head of the case before firing. Another start would be to measure the length of the case from the shoulder/datum to the case head of new ammo before firing.

The only method/technique a reloader has down pact is the' .002" shoulder bump'. A reloader that can 'bump a shoulder' .002" should be able to bump a shoulder .005" and measure the length of the case from the shoulder to the case head. I find bumping very limiting, I measure the length of the chamber before firing from the shoulder to the bolt face. Bumping does not get it done because I have a few long chambers, meaning I require cases with shoulders that are ahead of SAAMI specifications.

For me? That is not a problem, manufacturers do not make cases with long case bodies, again, not a problem, I find cases that have been fired in trashy old chambers or I form cases that are too long from the shoulder to the case head to chamber.

Then there is the $128.00 cost of the Redding comparator. A reloader with a few shop skills should be able to make a tool that measure the length of the case from the shoulder to the case head.

When deterring the distance off the lands, same thing. I use a transfer to adjust the seating die.

F. Guffey
 
I had 2 of the Redding Instant Indicators and was disappointed in them. Am curious to see if others had the same experience.

I had one for .308 Win and one for .223 Rem. Neither gave consistent, repeatable measurements of cartridge OAL or case headspace. (please spare me the “cases don’t have headspace” lecture :) ) Tried them with 2 different dial indicators and 2 digital indicators. The same inconsistencies across the board. And the headspace gauges that came with the RII’s were .001-.0015” shorter than multiple what I’ll call “gunsmith quality” commercial go gauges when I compared them using a Hornady headspace comparator. Overall, a big disappointment and I returned them for refund. Hopefully, others had better luck than i did.
 
I have found that calibrating the Hornady comparators against the full set of my Clymers chamber
headspace gauges results in about a 2-thousandths discrepancy. No big deal (and no different than when
using an RCRS Precision Mic) since it's the working comparator reading vis-à-vis a fired case that matters.
I just note it and move on.

The really big difference is that the Hornady comparators provide near instaneous/continuous feedback/tracking
when sizing, whereas the Precision Mic might take the better part of a minute to assemble/disassemble the
micrometer -- and the Redding looks like you've got to completely disassemble everything on the press itself.

.
 
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I made a tool in the mid '70s that was the fastest, I was told the users did not have time to do it correctly the first time, but always had time to do it over.

F. Guffey
 
I have found that calibrating the Hornady comparators against the full set of my Clymers chamber
headspace gauges results in about a 2-thousandths discrepancy. No big deal (and no different than when
using an RCRS Precision Mic) since it's the working comparator reading vis-à-vis a fired case that matters.
I just note it and move on.

Yeah, I found the same thing with the Hornady comparator, but like you say, no big deal. It's consistently off by the same amount. It wouldn't have been a big deal with the Redding tool either if the readout had been repeatable. But it was pretty much worthless as a comparator when it wouldn't give the same reading on the same case or go gauge 3 times in a row.
 
That's pretty disappointing. Was the variation in all the types of measurement it can make?

A couple of years before the Redding tool came out I made my own tool that resembles the instant indicator, but it is just for bullet seating depth. It measures the distance from the shoulder of a cartridge to the ogive of the bullet where it contacts the throat of the rifling. I figured that was what you really want to know, since the firing pin shoves the shoulder of a rimless bottleneck case up against the chamber shoulder, so that's what winds up determining the actual depth of ogive protrusion into the throat area.

OgivetoNeckComparator_zps8707d8fb.jpg
 
That's pretty disappointing. Was the variation in all the types of measurement it can make?

The problem was with both measurements, case headspace and cartridge OAL. I also remember one of the 2 I had would stick, that is, the internal bushing would jam up inside the die housing and I would have to tap-tap-tap the side of the die housing with a screw driver handle to unstick it. I tried everything I knew to try to get them to work consistently, but finally gave up and decided to send them back and just stick with the Hornady comparator. That was 2 years ago. Hopefully, Redding was just having some QC problems and has worked them out. I am a Redding fan, as I have a T7 press, a couple of their dies, and their case neck concentricity gauge… all are top quality products.

A couple of years before the Redding tool came out I made my own tool that resembles the instant indicator

Now that I have a lathe, this thread has me thinking about attempting the same thing.
 
I've chambered old and new barrels for many dozens of benchrest rifles and have never used a headspace guage. If you know the headspace of your action which is the measurement from the thread shoulder to the bolt face. Then you can chamber to the correct depth. We usually set up our headspace on the action (remington 700 usually) to measure .710. This was done by facing the bolt face square with the threads then then adjusting the shoulder to .710 from the boltface. Now with a supplied case the reamer is run in to the point that the supplied case will measure from the barrel thread shoulder to the case head .710.
Many times it was a wildcat cartridge supplied by the owner that was sized to his length but the shoulder wasn't blown out yet so I adjusted the head space to the case supplied. He would then seat the bullet for a tight push into the lands so the case would be held tight against the bolt face to fireform using a light load.
As strange as it sounds, I shoot one of my best groups while fireforming .222 mag cases with sharper shoulder. It measusred .106 for 5 shoots @ 100 yds.
 
Has anyone used the Redding Comparater to compare length of shells and base of a cartridge to point of contact to the lands?

then there is that part about testing the accuracy. Years ago I thought that came with the job as an 'assumed' skill. NOW? I am convened I was wrong.

I am the fan of transfers and standards. R. Lee in his book on modern reloading list the length of the case from 'a datum' to the case head. I assumed reloaders could find ZERO and I was never convened head space gages were made on Mars, I honestly believe people made gages, and now? I am convinced not all people can do it.

F. Guffey
 
Mr. Guffey,

I believe you have come to the correct conclusion!


Higgite,

Take a look at Sinclair's bullet comparator inserts. They'll fit your Hornady adapter. They are stainless steel and the hole is cut with something closer to a chamber reamer than the aluminum Hornady parts have. As a result, the Sinclair inserts contact the bullet a little further down, but it's nearer to where actual contact will occur anyway. They also make their own insert adapter. The only difference between it and the Hornady is that the Sinclair is centered and not offset to work with the Hornady Overall Length gauge, as Hornady's is.

I had a drawing of the gauge I gave to somebody, but I'll be darned if I can lay hands on it at the moment. I'll post it if I come across it.
 
Unclenick,

I should have mentioned I already have a set of the Sinclair inserts. Their adapter, too, I think, but I use the Hornady adapter.

I have given the Higgite Custom Redding Ripoff Instant Indicator a little thought, but family stuff keeps getting in the way. (I don't know why I expect my kids to grow up. I haven't, yet. :D) Would love to see your drawing if you run across it.
 
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