Powder Variance?

[woodsja]

Howdy,
I have a Hornady LnL with a case activated dispenser on my Lee Classic Turret.
I've never used a powder dispenser before and I'm getting a lot of variance in the throw weight with IMR 4064. My average over 14 throws was 42.32gr with a 95% confidence of +/- 1.32 grains. In other words 95% of my throws are going to be between 41.01 and 43.64 grains.

I know the LnL's supposed to have bad results with extruded powders but are they supposed to be THAT bad? Is there any way to make the situation better?


Results:
42.8
42.8
42.1
41.5
41.4
41.8
41.2
42.3
43
42.3
43
42.8
42.2
43.4

 

[Idano]

You can try a RCBS Uniflow Powder Baffle. I have a Uniflow Powder Baffle in all three of my powder measures: 2 RCBS Uniflows and one Honrady. I only run ball or flake on the progressive, I can live with +/- 0.1 grain deviation. However, when I load on my single stage with extruded I set it for -.05 and trickle in to target; with the baffle that is obtainable.

 

[woodsja]

http://www.midwayusa.com/viewproduct/?productnumber=493217

One of those?

The Hornady LnL came with one exactly the same that I'm using.

It kinda settled down after a pound or so of test charges. It's only off by ~ 0.5gr per throw now.

 

[woodsja]

Any particular way it's supposed to fit in there? I lined mine up so the baffle inlet holes are perpendicular to the throw handle direction.

 

[Walkalong]

It doesn't matter which way the baffle is lined up. Put it about 3/4 of the way up the tube, keep it filled above the baffle, work the handle of the press smoothly and evenly, not slow, not fast, bump it a little at the bottom each time, the same each time.. Practice.

 

[Bart B.]

Powder measures typically work best if they're mounted in a stand alone base. When they're mounted on a loading press, one needs to be extremely uniform and consistant in the way they operate the press, otherwise, the inconsistant bumps and shakes of the press will transmit to the powder measure. And that settles powder to different densities in their metering chamber.

If you measure dumps charge weights to less than a 3/10ths grain spread, that's good enough for 1/4 MOA accuracy through 200 to 300 yards if all else is right; even to 600 yards for some cartridges. Otherwise, you might want to weight each charge to that range.

 

[EddieNFL]

Loading Lincoln Logs, I mean 4064 requires the use of a chain saw.

 

[Walkalong]

When they're mounted on a loading press, one needs to be extremely uniform and consistant in the way they operate the press, otherwise, the inconsistant bumps and shakes of the press will transmit to the powder measure. And that settles powder to different densities in their metering chamber.

That is one of the reasons I size before loading. It is a great deal smoother loading without the sizing going on. Much easier to be consistent. Now if we were talking BR or HP, I would agree that a bench mounted powder measure would be the only way to go.

On his LNL, if he doesn't size while loading, he will find it very easy to be consistent, and that will help his spread.

41.2 to 43.4 is way too much. Although I have used some stick powders, I have not ever tried 4064 specifically, so I don't know how well it meters, but it should certainly do better than what the OP is getting.

If you measure dumps charge weights to less than a 3/10ths grain spread, that's good enough for 1/4 MOA accuracy through 200 to 300 yards

I agree, although, if I can get it, less spread makes me feel better.

 

[ranger335v]

No volumetric measuring of coarse materials will be consistant. Mounting the measure on a base that shakes (a press) only makes it more variable. If you want better consistancy you need to use a ball powder.

 

[Walkalong]

We used stick powder (albeit not lincoln log size) for Benchrest and threw all charges from a bench mounted measure with no weighing/trickling.

There is no doubt in my mind I could throw 4064 better than the results the OP is getting.

That said, no stick powder meters as well as ball powder. I am just saying it meters well enough.

Everything I have ever read or heard was that stick powders rule at long distance. Someone please correct me if I am wrong.

 

[woodsja]

It settled down a lot after I ran a lot of charges through it. I didn't calculate averages but I weighed three charges every three rounds and the farthest I saw from 42.8 gr was 41.8. I did find sometimes the powder throw would stick and I'd have to rethrow that case. The bottom limit for 168gr A Max in my manual is 41.8; if I threw one that was 41.4 or 41.2 am I going to have any issues when I go to the range?

Also: Has anyone had good experience taking their die apart and polishing the inside with a mandrel and polishing compound? I think it might smooth up the case forming but is it worthwhile?