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RDavies wrote:, but changing from jammed to jumped, always needs more powder to keep in the node.

Yes,
I had to add .5-.6gn to keep the same speed when switching to bergers "jammed versus jumped", should have read "jumped versus jammed"
Into the rifling= reduce charge for the same speed

Moving from jammed to jumped *should* reduce initial chamber pressure so if you need to get back up you would add more powder so I agree with that, the thing is if you do then replicate the pressure and accordingly MV with say a jump of .010" do you see the same accuracy and if so is it not a better move to start with a jump and reduce potential pressure spikes?

This is one of the reasons I moved from VLD to Hybrids in my 7mm.

Something I,m wondering about, is if you are running the low node, like I am, then maybe the jam gets to pressure up to where the powder likes to burn consistantly? Conversly, if you are pushing for a high node, then yes, the jumped Hybrids will be good for cutting peak pressures to a consistant, non peaky level. ??

dont get hung up on fps nodes its the pressure nodes you want to concentrate on.

My choice of hybrid was more based on the fact that they are not so sensitive to OAL so I was not going to end up putting 150 rounds up the barrel to find an optimum load as that is potentially 25% of the barrel life. With my F Open rifle I was trying to determine the optimum load in as few shots as possible which is never an easy thing to do.

Of course (moving off at a tangent now) this does mean I can never be sure in my own mind that I have the optimal load however if it can hold better than .5MOA at 600 yards then it should be good to go, I would apply this rule to most rifles other than bench resters who are looking for better than quarter MOA every time out. I think anyone that can hold the V at 1000 in their class is doing a lot more than just loading consistent and accurate loads.