6 posts
Joined January 2013

Inconsistent Powder Charge

I am at a loss to solve this problem so I am posting this to solicit some of the expertise from members that visit this forum. I am using a Dillon RL550B with Dillon Carbide Dies. I am using Aliant Power Pistol to load .40 S&W. I have loaded about 2,000 rounds and the powder measure threw a consistent 6.0 grains without variation. I slightly reduced the bell on the cases to 11 thousandths. Since that time the powder measure has been inconsistent: 6.0, 6.15, 6.3, 6.20, 6.0, 6.10, 5.85, 5.95, 6.5, 5.40. These measurements were verified using a Dillon Beam Scale as well as an electronic scale. I removed the powder assembly and cleaned it with alcohol. The powder readings are still inconsistent as above. I read in some post about the bell size but the reduction in size is within limits as stated in the Dillon manual. If the bell size is the problem why does that effect the powder charge? I would appreciate any advice I can get on this issue. 
3,222 posts
Joined July 2007

RE: Inconsistent Powder Charge

The case pushing up on the funnel activates the powder measure and pushes the powder bar over. Variations in case length change how far the powder bar travels. If you reduced the case mouth flaring from the initial setting and used a longer case to check flaring, then shorter cases may not fully activate the bar.

Increase the flare by turning the powder die down in 1/8th turn increments, and weigh several charges at the adjustment, until the powder charges become consistent again.