5Tom wrote:How many neck-resizes would you put on a case before replacing it with newer (or once fired) brass?
Apollo wrote:Depending on your bullet brand it is possible that inconsistant seating depth is inconsistancy in the bullets themselves. Certainly if they are measured from their tip (meplat) to cartridge base. Measuring to the ogive datum point is far more accurate.
Warrigul wrote:While it is possibly the projectiles themselves often as the case reload numbers rise it is simply inconsistent neck tension that is the issue with varying seating depths, especially if the primer pockets are getting loose too.
Chronos wrote:can you explain what you mean by seating depths can vary with neck tension?
i assume if the neck is not gripping at all then the bullet the bullet may slip into the case during handling or transport or be driven into the case on recoil but the actual seating depth during reloading should be consistent if your seating die is contacting the bullet correctly (eg: standard die with VLD bullets may cause bullets to seat shallow with more neck tension)
thanks, not having a go just want to clarify your post
Chronos
Warrigul wrote:No mechanical part has zero clearance.
With an old case the brass in the neck often displays different properties from case to case(as well as brass thickness- another story again), if using a normal neck or FLS die you can end up with varying tension throughout a batch.
Say you have set the seater to seat to a certain depth and by trial and error(measuring at the Ogive) find you are seating at a depth that gives you a land clearance of .010". Often most leave it at that and just seat an entire batch or 24 etc trusting it will be consistant.
If you go through that batch and check each individual cartridge you can find up to .020" variance when really (in my case) all you want is +/- .002", this is more evident in older cases that haven't been annealed or neck turned (I don't bother turning much as I seat to the lands to get pressure not rely on neck tension). Unless you are using some of the top end presses there is always some slack in any moving part and if there is varied resistance to the projectile being seated from the case you will end up with different depths.
I measure each individual target round nowadays.
Yes there are steps you can take to minimise neck tension variations but these are unlikely to be used by the average loader.
5Tom wrote:Great info there chronos and warrigal. Apollo - I checked that website and using the Winchester LR200 primers, they are the biggest.
I haven't annealed or neck turned at all, only ran the neck sizer. I'll see how I go with the new brass as they are all once fired. I'll run them through the FL die, trim down, debut the flash hole and go from there.
5Tom wrote:
Apollo - I checked that website and using the Winchester LR200 primers, they are the biggest.