Help - Redding Competition Seating Die

[constable79]

I recently purchased a Redding Competiton Seating Die due to their reputation for consistent OAL and the ease of adjusting for different bullets with the micrometer.

I'm loading on an RL-550, using FC brass (HST brass) from the same lot in 9mm. I'm loading Montanna Gold 124gr CMJs. All other dies are Dillon dies.

I set-up the die according to the instructions. I then adjusted the die to an COAL of 1.135 with all toolhead stations full when making the adjustment. I loaded five dummy rounds and they came out within the range of 1.1345-1.1355. I was certainly excited at this point.

I then loaded 100 rounds. Of the 100 rounds approximately 60 where more than .003 greater than my setting (1.138-1.141). I was expecting the first few and the last few rounds when the shellplate is not full to be off but not that many or by that much. I then reinserted the 60 rounds in station 3 and ran them thru the seating die and crimp die again. The 60 rounds then came out in the range of 1.1345-1.1365 with 2 or 3 outlyers in the 1.132 range. This is what I would have expected the first pass thru the press.

Any ideas on what I might be doing wrong?

Appreciate any help you can offer. Thanks.

Edited June 17, 2012 by constable79

[Racer377]

If the dummy rounds without powder (I assume?) came out perfect, but 60% of the charged rounds don't, I suspect you're using a compressed charge of some sort. That has been known to cause irregular OALs.

Edited June 17, 2012 by Racer377

[Jaxshooter]

When loading normally you will see the variance you are experiencing. When you run them thru one by one you there is nothing keeping the die from coming down to the same place on each stroke. With a full shell plate the variance in brass length will make a difference. Powder spilled on the shell plate or a primer that is not seated quite as far as another will also contribute to the variance.

I use Redding Comp Seating dies on all of my loaders and experience the same thing. The difference will not cause any problem with accuracy etc. Just load them up and shoot.

[constable79]

If the dummy rounds without powder (I assume?) came out perfect, but 60% of the charged rounds don't, I suspect you're using a compressed charge of some sort. That has been known to cause irregular OALs.

Racer, Thank for thought. Yes the dummy round was without powder. I'm not using a compressed charge as i'm only using 4.3gr of 231. I did not have this type of variance with the Dillon seater die.

Again, thanks for the input.

[constable79]

When loading normally you will see the variance you are experiencing. When you run them thru one by one you there is nothing keeping the die from coming down to the same place on each stroke. With a full shell plate the variance in brass length will make a difference. Powder spilled on the shell plate or a primer that is not seated quite as far as another will also contribute to the variance.

I use Redding Comp Seating dies on all of my loaders and experience the same thing. The difference will not cause any problem with accuracy etc. Just load them up and shoot.

JAXShooter,

Thanks for the advice

I'm not sure I understand how the length of brass would affect bullet seating as these dies seat off the ogive. I'm used to some variance but never saw this wild a swing with the Dillon Seater die.

Also I'd like to ask what is your thought on when I ran them thru a second time they all came out within a range variance that I would have expected (+/- .001 versus +/- .005).

My concern is that if I see this type of variance (especially longer) that I could run into a situation where the round is setback when chambered thus increasing pressures if I were to increase COAL in the future.

If you are also seeing this type of variance on your loads then I don't see what I gained by spending the money for this die over the standard Dillon die.

Thanks for your input.

[Racer377]

The bullets themselves will cause some variation. In my MG 124 JHPs, the bullets have some length variations, for example a batch I measured came out

0.579

0.579

0.575

0.575

0.581

0.579

0.578

0.576

0.573

0.578

But on my press, the variations in OAL are rarely more than +/- .003, My SD on OAL is .00174, so I'd suspect there's something going on there for them to come out .006 longer than they should, and that large a percentage of the time.

Maybe your dummy batch used 5 of the shortest bullets in the batch, thus throwing off your average OAL? Statistically unlikely, but stranger things have happened. That would make sense if all of your variations are to the plus/longer side.

ETA- the other possibility is maybe short stroking the press on the production run, but being more careful with the dummy/setup run?

Edited June 17, 2012 by Racer377

[Sarge]

Could it be that you are realizing, as I did, that the competition seater die is no better at being consistent than any other seating die. I'm not knocking it but it is not the magic bullet of reloading accessories as many think. I bought one and sold it after not getting the expected results then reading some threads on here about others who found the same thing. Again, not knocking it, but I bought a $25 die that is more consistent than the $80 die was.

[warpspeed]

The Redding die is designed to do two things ; repeatable adjustment & improved concentricity.

Keep in mind that the die makes contact with a place on the shoulder, not the tip so any variation the shape will result in a variation in the OAL. I guess the Dillon dies do too but the spring mechanism in the Redding must result in some play that creates the variation you are seeing.

That being said, we are not talking about benchrest loads here but if you get some satisfaction out of chasing perfection, I say keep it up. I don't bother anymore.

[constable79]

Could it be that you are realizing, as I did, that the competition seater die is no better at being consistent than any other seating die. I'm not knocking it but it is not the magic bullet of reloading accessories as many think. I bought one and sold it after not getting the expected results then reading some threads on here about others who found the same thing. Again, not knocking it, but I bought a $25 die that is more consistent than the $80 die was.

Sarge, I am with you on that. The micrometer feature is nice for quickly adjusting different bullets but from my experience detailed in the thread my results are much worse than the standard dillon die. I also have one for my .223 and 7mm which I haven't tried yet. So I guess I have 3 to sell.

[constable79]

The bullets themselves will cause some variation. In my MG 124 JHPs, the bullets have some length variations, for example a batch I measured came out

0.579

0.579

0.575

0.575

0.581

0.579

0.578

0.576

0.573

0.578

But on my press, the variations in OAL are rarely more than +/- .003, My SD on OAL is .00174, so I'd suspect there's something going on there for them to come out .006 longer than they should, and that large a percentage of the time.

Maybe your dummy batch used 5 of the shortest bullets in the batch, thus throwing off your average OAL? Statistically unlikely, but stranger things have happened. That would make sense if all of your variations are to the plus/longer side.

ETA- the other possibility is maybe short stroking the press on the production run, but being more careful with the dummy/setup run?

Racer,

I measured my bullets before starting and my readings were in line with what you have listed with most in the .576-.579 range. At the time i was not concerned with the variation because the Redding seats off the ogive and not the bullet tip as the dillon seating die. I don't have the proper tools to compare but this is leading me to believe the MG's vary just as much in the ogive area as they do in length.

Thanks for all your imput.

[kineteks]

Just an observation.... am I wrong or will bullet OAL not impact round OAL with a die that uses the tip of the bullet to seat? The die is seating the bullet to depth based on the bullet tip and whatever is locating the case, base of the brass, shell-plate whatever. A longer or shorter bullet will affect how deep the bullet goes into the brass, not OAL. If the Redding die uses the ogive area and there is a length variance between where the seating die contacts (dia. = X) and the bullet tip... that WILL give an OAL difference. Does this mean that as far as tight tolerance round OAL is concerned a die that uses the bullet tip will give better results that one that uses the ogive area?

That said, I wish I shot well enough for +/-.005 to make a difference....

[constable79]

Just an observation.... am I wrong or will bullet OAL not impact round OAL with a die that uses the tip of the bullet to seat? The die is seating the bullet to depth based on the bullet tip and whatever is locating the case, base of the brass, shell-plate whatever. A longer or shorter bullet will affect how deep the bullet goes into the brass, not OAL. If the Redding die uses the ogive area and there is a length variance between where the seating die contacts (dia. = X) and the bullet tip... that WILL give an OAL difference. Does this mean that as far as tight tolerance round OAL is concerned a die that uses the bullet tip will give better results that one that uses the ogive area?

That said, I wish I shot well enough for +/-.005 to make a difference....

Kineteks,

As explained to me by both Redding and Dillon techs, the following statements are correct.

1. If using a seating die that seats off the bullet tip, if you measure using calibers you will get a more consistent OAL reading

2. If using a seating die that seats off the ogive, if you measure with a bullet comparator you will get a more consistent OAL reading.

You are correct when you state that bullet variance will not affect round OAL when seating off the bullet tip if you measure with a caliber. If you measure with a bullet comparator you will see a variance since it measures off the ogive. Also, in this case, you will have a greater variance of each round from the chamber size on the ogive to the distance to the chamber.

As you also summarized, when using the redding competition seating die, you will see a wider OAL variance when you measure with calibers. Assuming the bullet variance is between the ogive and bullet tip, the redding competiton seating die will put the same "length" of bullet in the case. When seating off of the bullet tip, the bullet length variance will cause the "length" of the bullet seated in the case to vary.

As to your question about tight tolerance and OAL the answer should be no. The redding competition seating die is designed so that the seating stem is approximately the same size as the chamber. Therefore if using the redding die you will see a larger OAL variance when measure with caliber but there should not be an issue other than you may have a magazine fit issue if your desired OAL is close to max magazine length. There should not be any issue with the bullet contacting the rifiling as long as the OAL was setup for your individual gun. I would think the Redding die would yield better accuracy since the distance from ogive to chamber engagement is consistent for all rounds. As you stated, i'm not sure my shooting capability would notice the difference except maybe longer distance rifle shooting.

This was the first time I have ever measured my bullet lengths because of the wild OAL range. I'm not sure if this range of variance is standard with Montanna Gold bullets or not. I did measure some Nosler 308 bullets I have and their variance was much tighter, in the .002 range.

The purpose of my post was to educate those thinking of using the Redding Competion Seating die of how it is designed to work and alert them they would probably see a wider OAL variance if measuring with a caliper.

Thank you very much for your inputs.