I'm having trouble developing a load for my 6.5x55, I am after a bit more velocity I believe I am only getting around 2500 fps and am already getting stiff bolt lift and extractor marks if I go up .5grain. The rifle is a ruger m77 with 22inch barrel I would have thought 2750 should be well within reach. This velocity is figured from what the books say I should be getting with the powder charge and from a proven trajectory. Crony is on the Xmas list.
The load is 140gr sst, 41grns AR2209 this is well under book max, I have three areas I'm looking at.
I seam to get really dirty necks, I have heard this can be from underloading which doesn't seam to make sense, I'm just a bit confused by this if the brass is showing max preassure surely the necks should be sealing.
The brass is PPU so it may be a low quality, as said I'm getting stiff bolt lift and extractor marks but I would have thought even soft brass should handle his load comfortably. I have got a batch of hornady brass left over from a couple of boxes of superformance I could try.
The seating depth, currently I have a .1mm jump to the lands, I am wondering if this is to close and causing some preassure spike.
My question for you is what would you try first change the brass or lower the COAL?
If I change brass or COAL do i need to lower the charge weight and work back up and by how much?
Thanks every one.
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