Lyman Gen 6 powder measure flaw

M

maccluer

New member
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Lyman Products Corp
475 Smith Street
Middletown, CT 06457
800-225-9626
800-423-9704
860-632-2020

October 6, 2015

RE: Gen 6 Powder Measure Failure

Dear Lyman:

Your new Gen 6 powder measure is ideal for benchrest shooting but for one flaw:
the rotating dispensing tube seizes up after approximately 400 grains of powder.

The trouble seems to be that small cut sticks of powder eventually prevent the two tube seals at either end of the tube scoop from rotating within their envelopes. The incapacitating friction occurs at the circumference of the envelope inner diameter, not at the contact of the seal with the tube.

Removal of the two seal/envelope units solves the seizing problem but then much powder is lost to leakage.

We competitors typically use Vit N133, and to a lesser degree IMR8208, H322, and other similar speed powders. In the heat of competition there is no time to do a through cleaning before continuing. After the first cleaning, the time-before-failure decreases monotonically. This Gen 6 flaw surfaced during the NBRSA Nationals in St Louis this September.

Please find a fix. Your measure could become universally used were it not for this fatal flaw.

Chuck MacCluer
6mmPPC.com
 
I wold be very interested since I was about to order it at Sinclair.

I can easily switch to another company at around the same price.
 
maccluer said:
COPY COPY COPY

Lyman Products Corp
475 Smith Street
Middletown, CT 06457
800-225-9626
800-423-9704
860-632-2020

October 6, 2015

RE: Gen 6 Powder Measure Failure

Dear Lyman:

Your new Gen 6 powder measure is ideal for benchrest shooting but for one flaw:
the rotating dispensing tube seizes up after approximately 400 grains of powder.

The trouble seems to be that small cut sticks of powder eventually prevent the two tube seals at either end of the tube scoop from rotating within their envelopes. The incapacitating friction occurs at the circumference of the envelope inner diameter, not at the contact of the seal with the tube.

Removal of the two seal/envelope units solves the seizing problem but then much powder is lost to leakage.

We competitors typically use Vit N133, and to a lesser degree IMR8208, H322, and other similar speed powders. In the heat of competition there is no time to do a through cleaning before continuing. After the first cleaning, the time-before-failure decreases monotonically. This Gen 6 flaw surfaced during the NBRSA Nationals in St Louis this September.

Please find a fix. Your measure could become universally used were it not for this fatal flaw.

Chuck MacCluer
6mmPPC.com
Click to expand...
Chuck:
Some of the U-Tube demonstrations discuss this.
Their solution was to only put small amount of powder (Maybe 1" of powder) in reservoir/powder tube at a time.
Too much powder causes the unit to operate slowly also.
The larger powders (Stick) are more likely to have this problem.
I don't have one so none of this is from experience--just viewing from internet.
CLP
 
Lyman replies

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Tom Griffin tomg@lymanproducts.com
7:47 PM (21 hours ago)

to chuck

Dear Mr. MacCluer,

In regards to your recent letter, powder should not be able to get behind the rubber seals to bind up the powder feed tube. If this is happening, we would suspect that the seals are a little too large in diameter. The scale should have come with a spare set of seals. Did you receive these and did you try the other set? If not, or if the other set had the same issue, we would be happy to check out a new set of seals and send them to you.
Tom Griffin
Tech. Manager

Chuck MacCluer <maccluer13@gmail.com>
8:30 PM (20 hours ago)


MY REPLY MY REPLY MY REPLY


Tom:

The binding is not occurring where seals mate with the tube but instead where the seals rotate in their sleeves. The seals are evidently designed to rotate with the tube.

When I change out the seal set to the included second set, it is only a matter of time before the bind up occurs again with the new seals.

I would very much like to try some alternate seals to see if the problem disappears. I will be delighted to pay for the additional samples.

Thank you for your attention to this problem.

Chuck
 
Chuck,

They are great when they work. I bought one and it lasted a week. I returned it for a full refund. Billy's lasted about 4 months, but quit working at the World Championships. He sent it back to Lyman. I'm curious to see what they do.

Bart
 
What color are the seals?

If they are black, then they are rubber based. You could try replacing them with the blue or red silicone based units. They last longer and don't shrink when the weather and humidity changes
 
To clarify, we are talking about o-rings

Here, not actual seals or gaskets?
 
M Casselton said:
Here, not actual seals or gaskets?
Click to expand...

No, they are not O rings. They are disks of thin rubber-like sheets with a hole at the center that (too) tightly fits the dispensing tube. These disks rotate within square sleeves that seal away the outer compartments from the powder.
In my opinion the problem is that the disks fit the tube too tightly --- they were probably meant to remain stationary while the tube rotates. Because of this too tight a fit, the disks rotate with the tube within their sleeves, and the powder flakes gum up the space between the disks and their retaining sleeves. Proposed solution: With a rat-tail file, slightly enlarge the disk's center hole so that the tube rotates freely while the disks remain stationary.
 
maccluer said:
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Tom Griffin tomg@lymanproducts.com
7:47 PM (21 hours ago)

to chuck

Dear Mr. MacCluer,

In regards to your recent letter, powder should not be able to get behind the rubber seals to bind up the powder feed tube. If this is happening, we would suspect that the seals are a little too large in diameter. The scale should have come with a spare set of seals. Did you receive these and did you try the other set? If not, or if the other set had the same issue, we would be happy to check out a new set of seals and send them to you.
Tom Griffin
Tech. Manager

Chuck MacCluer <maccluer13@gmail.com>
8:30 PM (20 hours ago)


MY REPLY MY REPLY MY REPLY


Tom:

The binding is not occurring where seals mate with the tube but instead where the seals rotate in their sleeves. The seals are evidently designed to rotate with the tube.

When I change out the seal set to the included second set, it is only a matter of time before the bind up occurs again with the new seals.

I would very much like to try some alternate seals to see if the problem disappears. I will be delighted to pay for the additional samples.

Thank you for your attention to this problem.

Chuck
Click to expand...


Chuck...
Did you ever get a reply from Tom Griffin at Lyman?? What did he say?
 
Lyman Gen 6 malfing redux

XBBR Shooter said:
Chuck...
Did you ever get a reply from Tom Griffin at Lyman?? What did he say?
Click to expand...

Tom:

No reply yet. I have delayed a follow up letter because I wanted to try a fix. I used a rat-tail file to open up the seals so they would not bond so tightly to the dispensing tube. It made no difference. ---binding recurred after about 300 grains.
I am now waiting for 3mm-thick sheets of teflon. I will fabricate precision one-piece seals that will not rotate. The present seals use a sticky rubber O-ring-like seal that rotates within a sleeve, much like the 5 1/4-floppies of yesteryear. Stay tuned. Chuck
 
maccluer said:
Tom:

No reply yet. I have delayed a follow up letter because I wanted to try a fix. I used a rat-tail file to open up the seals so they would not bond so tightly to the dispensing tube. It made no difference. ---binding recurred after about 300 grains.
I am now waiting for 3mm-thick sheets of teflon. I will fabricate precision one-piece seals that will not rotate. The present seals use a sticky rubber O-ring-like seal that rotates within a sleeve, much like the 5 1/4-floppies of yesteryear. Stay tuned. Chuck
Click to expand...

Give Tom Griffin a follow-up poke, or your question will go unanswered.
 
XBBR Shooter said:
Give Tom Griffin a follow-up poke, or your question will go unanswered.
Click to expand...


COPY COPY COPY (Email to Lyman)


Tom:

Any progress in curing the bind up of the Gen 6 powder measure?

I've tried enlarging the diameter of the O-ring seals so that they no longer turn with the dispensing tube but their sticky rubber has too much stiction.

I am waiting for sheets of 3mm Teflon with which to manufacture fixed seals.

I will let you know if that is successful.

Thanks for any progress toward a solution. It's otherwise a magnificent machine.

chuck@6mmPPC.com
 
RCBS chargemaster

Are y'all getting good competitive throws with your chargemaster.
I talked to a couple of friends that load with chargemaster and says it throw powder great.
I can't seem to get mine to throw competively. What am I doing wrong . Any tricks I need to know about.
 
You need to reprogram the speeds. Rcbs techs can help you or there is plenty of info around the web. Theres 3 settings for trickle stops to optimize it for your powder
 
So is it overshooting or showing the correct weight but not proving out on the scale? If its the first then you need to work on the programming numbers increasing the last of the 3 so it trickles farther away from target. If its the latter thats just a chargemaster and you shouldnt be double checking it with such a nice scale
 
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