lyman 55 powder dispenser

[treeman]

Bought one of these a week ago and battling.I use s365 & s355 powder.40 odd powder throws and 40 odd differant weight readings.Took it back to Aquila Firearms in PE and Chris the owner tested it and said its right.You must always use a powder trickler to correct a charge dispensed by a powder dispenser. ?????? This seems to defy the reason I bought it and the adverts (accurite to 1/10th of a grain *accurite to a fraction of a grain * constant precision) if I still have to trickle the final powder I might as well use the spoon and trickle the finl.Why spend R1600 for the same result --- any comments ???

[THOMAST]

treeman, S355 &S365 are both extruded propellants (little cylindrical granules) and you will always get variations in the weight when using a powder measure, because, depending on how the propellant granules fall into the volume chamber of the powder measure and how they fit together, you are going to have variations in weight per volume.
S335, which is a smaller granule size , gives less variations and the Spherical propellants(ball like granules) like S341 &S361 give more constant volume/weight ratios. (I find spherical propellants are too temperature sensitive for my liking)
The trick is to keep the powder/propellant collumn at a constant density, by maintaing the exact same technique with each dispensing. Swing the dispencer lever with the same pace each time, and if you tap the unit , do so every time.
(Fill a small tube with propellant and tap it gently- see how the propellant drops deeper into the tube as it settles and compacts - this is what happens in the cylinder of your powder dispenser)
The problem with the extruded propellants is that some get caught and cut between the cylinder and body of the dispenser when you rotate the dispensing lever and this disturbance upsets the apple cart, because you can't maintain a constant motion.
Some dispencers even have a baffle in the powder cylinder to try and keep the powder density constant.
When I use a dispenser, I would dump approx.90% of the weight onto the scale and then trickle the rest in, using a powder trickler

[treeman]

In the end I ran to ol Gerrie schults of Custom Guns (GS Custom bullets fame)
amazing 10 minutes later had it throwing 365 at 1/10 and 2/10th of a grain varience time after time.Just how you do it and a small mod to the housing - a piece of spacer.

[carlp]

treeman, can you maybe tell us were the spacer was installed?

[treeman]

You bush out the drum attached to the handle with some of that gasket material paper or exray plastic. That drum can move slightly left right in its housing oviusly the space then varies. Take end nut out cut spacer put between and tighten up- if you get stuck email address and will email photo

[RyanD]

I hve just got one of these, so I am curious to see the mod, please check your PM for my email, I would appreciate a photo.

Just a question, the manual says to completely degrease the unit with alcohol or degreaser prior to use, did you do this, I am thinking of doing this job tomorrow ?

Thank you
Ryan

[Gerard]

A Lyman 55 is not supposed to throw equal weight charges. You have a choice between equal weight charges and equal volume charges. You cannot have both except by accident. Equal volume charges are more consistent than equal weight charges. So, if your powder measure throws charges that are not of equal weight, but the chronograph says the speed variance is acceptable, it is doing what it is supposed to do.

Do the test: Load 5 over the scale with trickled charges and load 5 with a Lyman 55 that is properly operated. Mark the ammo loaded with the powder measure. At the range, put up two targets, one marked "scale" and the other marked "measure". Fire a shot or two with non test ammo. Put the test ammo in a bag and mix them up. Pull a round at random from the bag and, depending on what it is marked, fire it for group at the appropriate target. Finish the 10 rounds, shooting at 2 minute intervals.

The targets will say which is the best method.

[treeman]

G but then how do you measure the first charge----
How do you replicate volume at a later stage to redo the same thing 9Other than storing a set up powder trickler.
I only load like 40 rounds at a time, so replicating will become a whole developement process or what

[Gerard]

If you use (for example) 45.5gr to give the speed you want, that would have been the average load thrown by 5 consecutive loads with the Lyman 55. When you load again, and the measure has not been used for another charge in the meantime, just carry on loading again. By all means check the charge to see if it is still set to the charge that you think it is. If it has been set to another charge, just set it to give an average of 45.5gr with five throws.

[Stonewall2]

I have a Lyman 55 with a Culver conversion (new drum with clicks).
I found that by adding the Hornady plastic powder baffle it keeps a constant powder charge in the case.

hornadypowerbaffle_996d06a62204eec2edd4fdcd56630662.jpg

I use this for Benchrest shooting but have been impressed with IMR-4350 in hunting loads.

Glenn