WST with Dillon Xl 650

[Jukez]

Anyone notice some some variation in velocity using WST. I am getting a range of 917 to even as high at 970 sometimes randomly. I am checking the powder in random cases as I go to ensure they are getting 5.0g at 1.185 using BBI. Even then I tend to range from 935-942 which feels a little better.

[cslafrain]

A couple of things:

1) Polish the powder die - Polish the powder die - Polish the powder

2) Auto indexing presses tend to snap into position at times and can expel a little powder out of the case - enough to make a difference - search the forums as there are plenty of topics on it.

3) When at the chrono to get the most consistent results - tap the powder down so that it is closest to the primer. Do this by elevating the muzzle and slightly tapping the side of the weapon - must be done on each case.

4) A range of 935-942 is phenomenal - expect an ES number of about 20 FPS or a little bit greater. Try to keep a Standard Deviation less than 10.

5) Please remember that variation comes in various forms - range brass, press cycle smoothness, temperature & humidity, etc and each has an impact at the chrono

[bigcraig]

#2 and #5 from the above post is what has given me issues in the past.

While I have chrono'd all my ammo with mixed brass and all made PF, I have found that using brass of the same mfg always has a tighter deviation range across the board.

[razorfish]

WST can be difficult to tame. I've found that with WST it's especially important to maintain a smooth consistent stroke while loading. When I first started using WST I was lucky to achieve a standard deviation of 18 on a ten shot string. I've now got WST maintaining an SD of 10 using BBI projectiles. Be patient and don't give up.

Also be sure to make careful temperature notes while testing as you'll find yourself reviewing that data throughout the year.

[njl]

A couple of things:

5) Please remember that variation comes in various forms - range brass, press cycle smoothness, temperature & humidity, etc and each has an impact at the chrono

Are you using sorted (by headstamp) brass? Have you checked the consistency of the length of the bullets (before loading) and consistency of OAL of your finished cartridges? Inconsistencies in any of these can affect internal case volume, which will affect pressure, which will affect velocity.

Are you finding any powder on your shell plate/ram after a loading session?