Seating depth inconsistant

[D.Camilleri]

Since I have been trying to be very careful with my seating depth in my 338 rum, I am noticing that my lengths are varying up to .010. I have an older rock chuck reloading press and I am using a redding micrometer seating die with a vld insert for seating my Berger 300 gr OTM's and a rcbs seating die to seat my 300 gr accubonds. I seat each bullet twice since I am compressing powder and I usually still have +- .005

Any thoughts?

 

[EricL]

If you are measuring off of the tip of the bullet it could be the bullet tip itself that is that far off from one to the next. The other thought I would have is, how compressed? The reason I say is my shooting partner was telling me that he had some loads that were so compressed that after seating the pressure would push the bullet back out just a little bit. I think he switched to a faster powder and decreased the charge just a bit to fix it.

 

[dok7mm]

You didn't mention whether you are talking about CBTO length or COAL length. If you're referring to base to ogive, it could be you don't have enough neck tension to keep your bullet from backing out of neck due to powder compression. The Redding comp seater does not play well with heavily compressed loads. If you're referring to OAL, you'll have to sort bullets, at least base to ogive length, if you are not already doing it. Hope you get it figured out.

 

[D.Camilleri]

Well, I put my bullet comparator on my digital caliper and measured all the shells I loaded yesterday. 90% were within .001 and several were off by .005+ and -. The bergers were very uniform and the accubonds a little less so. Time to go shoot again and see how it goes.

 

[Gene]

With compressed loads, inconsistent OAL is a given.

 

[Corey Schwanz]

Redding's competition seater does not play well with compressed loads and they recommend not doing it if possible. As others have mentioned, measuring base to tip may give more erratic measurements than measuring CBTO. I would imagine the VLD stem is giving you enough clearance, but it might be worth the time to check to make sure the bullets are being cupped properly by the stem and you aren't bottoming some of the out on the tip inside it. Take the stem out of the die and grab a few bullets to see how they are contacting.