Small powder charges in Hornady LNL crushes case!

[Taterhead]

The binding is the same when worked by hand. If I raise the charge to above ~4.0 gn the resistance disappears completely. Drop the charge down to ~3.5 gn and it takes both my hands to push the rotor up.


All my four measures (I have three with case activators and one for a RCBS stand for my single stage reloading) came with only one drum.

Like I said in my earlier post, I'm most certain that the disc part of the metering screw is emerging through the cylinder and contacting the housing body when activated. Screw it out a little, it will have the needed clearance (as you've already detected). Unfortunately, that is the lower limit of the potential charge volume.

[Whistler]

Like I said in my previous post... If I empty the measure there is no binding, even with the micrometer set to the low charge values.

[ph4570]

A wild guess -- maybe at the low setting there is a small enough gap between the adjustment ram and the powder measure body that individual powder kernels jam up between the ram and the body. But with larger charges the gap is big enough for kernels to slide out of interference path.

edit addition -- From your original post, I see that is your suspicion as well.

It would be interesting to know what the gap is between the ram and the drum edge at that low powder setting.

Also, have you tried a non-micrometer type powder adjuster ram?

[Whistler]

Yes. I have two without micrometer and one with. Same thing on all three, at about the same charge.

[OS OK]

A wild guess -- maybe at the low setting there is a small enough gap between the adjustment ram and the powder measure body that individual powder kernels jam up between the ram and the body. But with larger charges the gap is big enough for kernels to slide out of interference path.

edit addition -- From your original post, I see that is your suspicion as well.

It would be interesting to know what the gap is between the ram and the drum edge at that low powder setting.

Also, have you tried a non-micrometer type powder adjuster ram?

You know I'm inclined to agree with you too. Just now I looked at this powder in the National Center for Forensics Science…http://www.ilrc.ucf.edu/powders/samp...?powder_id=480
That powder doesn't look like it would roll as the meter slot goes by the case where kernels get rolled in or out of the metering hole and sliced…It looks like a jam fixin to happen with that metering screw almost all the way in. ESPECIALLY is he is using the larger rifle rotor where that little space will be quite small at that weight charge.
Can you pull it out and see if it's 'very' close…measure it? Isn't the center of that rifle metering screw a dome shape?

charlie

Edit: Looking at the N310 those kernels are almost the same diameter as the N340 but they are shorter…could be that not having the longer grains they allow that wiping action of the rotor without having to shear/cut too many if any.

This is a pretty good brain teaser.

[Lloyd Smale]

I have 4 of them and they all came with 2 drums and two adjusting stems. One for small charges up to about 10 grains and one for larger charges. Did you buy them used? I'm sure that's your problem. Pick yourself up the small charge drum and adjuster.

The binding is the same when worked by hand. If I raise the charge to above ~4.0 gn the resistance disappears completely. Drop the charge down to ~3.5 gn and it takes both my hands to push the rotor up.


All my four measures (I have three with case activators and one for a RCBS stand for my single stage reloading) came with only one drum.

[Lloyd Smale]

this is what you need. http://www.midwayusa.com/product/164...ering-assembly

[Whistler]

So... The plot thickens, we're getting closer, I smell something rotten, etc...
Or just the regular Star Wars quote "I've got a bad feeling about this".

After about a dozen emails to and forth with Hornady customer service, and some confusion to what parts I have, this is a summary:

Measure 1: Old style deluxe, one rotor, two inserts. Allen screw fastens the insert in the rotor.
Measure 2: Old style deluxe, one rotor, two inserts. Allen screw fastens the insert in the rotor.
Measure 3: New style standard, one rotor, one insert. Push button to release insert.
Measure 4: New style standard, one rotor, one insert. Push button to release insert.

All four measures behave the same way:
3.5 gn N310 = no problem3.5-4.5 gn N320 = binds. Empty measure at same setting, no binding.
3.5-4.5 gn N340 = binds. Empty measure at same setting, no binding.

Hornady writes that I have to get the pistol rotor and insert for measure 3 and 4. This is in line with the advice given in this thread.

Hornady then writes that measures 1 and 2 are "the old style deluxe measures" and that "they are meant for rifles only, they will not do pistol at all".

So far the specs I have been able to find is this:
"Standard insert and rotor" will do 15-100 grains powder.
"Pistol insert and rotor" will do 0.5-17 grains powder.
"Bench rest insert and rotor" will do 20-65 grain powder.

There is no spec at all regarding the "old style deluxe measure". My own experience is that the "pistol" insert for the deluxe measure will go to about 17 grains, then I have to put in the "rifle" insert. Hornady though continues to say that they are the "same size insert except for the adjustment position is smaller in the pistol insert."

On the standard measure I can go down to 4.5 grains N340 without binding, but the throws will be uneven, one will be 4.2 and the next 4.8 grain. I accept that I will need a new rotor and insert for the standard measures 3-4.

However, the pistol inserts for the deluxe measures should be able to do down to 0.5 grains if I understand correctly. I still cannot understand what is wrong and causes the binding. The powder kernel size is obvious, since I don't have this problem with N310 using charges down to 2.0 grains.

[Whistler]

Some Visual explanation as well:

Standard insert (also available with micrometer head):

Standard pistol insert (also available with micrometer head):


Bench rest insert:


Old style deluxe pistol insert (fastens with allen screw):


Old style deluxe rifle insert (fastens with allen screw):


The standard measure also has a wider powder container.
The benchrest/deluxe measure is thinner, they also have a smaller rotor.

My "old style deluxe" measures was called "benchrest" when I bought them. Apparently Hornady changed the name and the new benchrest measure is for rifle only.

The deluxe pistol insert has the same outer diameter as the rifle insert, but has a hollow cavity where the powder goes.