Seating Depth variability: consistent groups

[z7]

i was doing some further testing going and trying to work around the problems with seating depth variability found in this thread
http://www.thehighroad.org/showthread.php?t=768022

in short, my lee dies and hornady 178 bthp do not agree, giving me as much as .025" in OAL variation, i believe it was several things including the nose touching the seater stem. the variation was all over the boards and i could not get anything consistent. it was all over the place

round two: i use the RCBS seater die that came with my small base FL sizer.

i loaded up 40 rounds this evening over 44.5g of varget. about 18 of these were very consistent, 2.805"-2.809", i will take that.

another 22 were 2.831"-2.835" also very consistent. there was no in between.

also, the seater stem on my die left a nice ring around the nose, very consistently. this was not happening with the lee die.

so i took the long ones, adjusted the die and now i have 40rds with the same OAL so they will feed through my AR10. if the weather and other things cooperate i will see how they group tomorrow.


in the expert opinion of the THR, is this a bullet problem or a die problem, or a combination? there is up t .01" variation in the bullets length (1.343" to 1.353")

 

[jwrowland77]

Measure to the ogive using a bullet comparator.

It's common to have OAL differences. If you have differences when measuring to the ogive, then you have issues somewhere else.

 

[Walkalong]

The OAL differences mean nothing. As posted, check base to ogive.

 

[JimKirk]

the seater stem on my die left a nice ring around the nose, very consistently

Take a piece of 400/600 wet/dry sandpaper and push it into the seater stem with your finger tip ... make several twist of the stem .... just enough to break the sharp edge that is there ... then no more lines on your bullets...