So you think size doesn't matter?

[Shuz]

I recently discovered that size does matter! The rifle is a Remington 700CDL in .35 Whelen with a stock factory 1:16 twist bbl.
The load is 25g of 2400 behind a 206g Lee 35-200FN that has been quench cast to achieve a hardness of Bhn 22.Primer is CCI 200 and boolits were loaded to an OAL of 3.075".

The following are the results of 4 separate 5 shot strings measured over an Oehler 33 chronograph:

Bullet sized diameter: .359" ES 81 Ave 1923fps SD 32
.359" ES 29 Ave 1968fps SD 12

Bullet sized diameter: .360" ES 86 Ave 2136fps SD 36
.360" ES 13 Ave 2190fps SD 5

Whoda thunk that a mere .001 difference in sizing would result in such a difference in velocities!

The sad thing is that none of the 5 shot groups at 100 yards was good enuf for CBA competition with the best measuring 2.497" .
I always seem to get one "flyer" out of each 5 shot group. Oh yes, all boolits were weighed, and as each was shot, there was no discernible difference in shot placement due to weight differences; which only amounted to +-1g from 206g.
Comments!

[Ateam]

I have found recently that to shrink my group size (after load development of course) I had to work on my cheek weld, and raise my comb height. I was working on a tika t3 light 300winmag, and was unable to get the groups much below 1.5 inches at 100y, and I knew the gun was capable of better. I wasted loads of components chasing phantom accuracy issues when stock fit on a factory rifle was the real problem.

[17nut]

You dont mention lubing but here is what i have found:
A bullet can have to much lube and be "slippery" ie. flyer.
I started to lube just the bottom 1 or 2 grooves and the fliers went away.

[Shuz]

I don't think I'm getting lube purging, but I could try some with lube wiped off all but the smallish area ahead of the gas check and see what happens. Or, could try some tumble lubed boolits and see what happens.

[Sakoluvr]

I would try using Ramshot TAC instead of 2400 and compare that velocity with 2400.

[Shuz]

I've never seen Ramshot TAC in my area, but I do have some Accurate 5744 that I might try after exhausting my trials with 2400.