Better consistency

[codym]

Hey guys been reloading for a long time but never to the point that I am now. I'm having trouble keeping my ES down. I'm loading .243 win with H4350 BR primers, lapua brass and 110 SMK's. I dont weight sort Lapua brass but may need to start. I'm FL sizing with a forster bushing bump die .002 off the shoulder and .002 under the outside daimeter of a loaded round. I then run a .241 mandrel through the neck. I'm trickiling powder on to a FX-120 I. Trim to length on a Forster trimmer and hand primed with the RCBS hand tool. SD is ok like 11-12 avarge over a lab radar but I get these big ES usually one or two rounds 30-40 FPS slower. Any ideas or suggestions? I'm thinking of re-working the load. I'm getting 3080 on virgin brass then drops to 3060 on the subsequent loadings. 39.6 gns of powder.

 

[antithesis]

Sounds like you are outside a node. Go up (unless you are already pushing max) and down 0.3 grains and see if you find something different.

• Check concentricity. If you don't have a gauge, when you size your brass take 2 more runs by turning the brass 1/3 each time.
• The velocity change is most likely a result of the virgin brass not being fully expanded. Once you fire, you get more volume. You should be doing load development with fully expanded brass (more volume means less pressure/slower velocity).
• Annealing is another thing, but likely not the root cause.
• You may want to try without using the expander. I have tried with and without and gotten mixed results. I gave up on trying.
• Proper chamfer and brushing necks are a must to avoid scoring the bullet when seated. Guessing you are already on top of this one.

 

[codym]

I was thinking along similar lines. I’ve got 50 rounds loaded with the SMKs then I’m going to move on to the 115 Dtacs and rework the load. I’m going to mess with some with the mandrel and without and try the turning deal. Annealing will be done before the 3rd reload for sure

 

[pbatesaz]

I agree with antithesis, probably outside a node. With an SD of 11 or 12 your expected ES at the 95% level is 44 to 48... probably not the load you are looking for.

 

[MtnCreek]

Sounds like it could be a seating issue. Either bullets bottoming out in stem or trying to load too close to the rifling.