Can I go shorter??

[weebeestie]

By suggesting the OP load 20 thou off the lands you are taking him back to where he started, factory loads shoot ok in the rifle its his reloads where the problem lies, possibly originating in this "load as close to the lands as possible" mantra that seems to have taken hold .

The OP has got it into his head that starting at the lands and then backing away untill he finds a sweet spot is the way to go. Hes had no progress with backing of thats why I said go back close to the lands.
Hes been cleaning the barrel before each test string effectivelly turning a test group into fouling shots which will have poor to zero accuracy.

I am guessing/hoping that you worked up a powder load at book COAL then picked the tightest group that didn't show any pressure signs and started to change the length to fine tune

Im with pothunter here.
Reload development starts with powder load testing and then COL for fine tuning

[Parabuteo]

The OP has got it into his head that starting at the lands and then backing away untill he finds a sweet spot is the way to go. Hes had no progress with backing of thats why I said go back close to the lands.
Hes been cleaning the barrel before each test string effectivelly turning a test group into fouling shots which will have poor to zero accuracy.


Im with pothunter here.
Reload development starts with powder load testing and then COL for fine tuning

Yep, cos sometimes you aint going to be able to mess with COAL much in a mag fed rifle

[Ka-Boom!]

I've skimmed this thread, so apologies if I have the wrong end of the stick, or am repeating advice above.
It sounds like your reloads and PPU factory shoot awful, but RWS factory shoots OK? I have never had PPU ammo shoot well in any of my rifles, and maybe your barrel doesn't like the 75gn Vmax.
Therefore try some reloads with the same bullet as the RWS factory ammo, or same weight bullet if you can't find the exact one. Try a middle of the book load at standard SAAMI length. Subsequent fine tuning charge and COAL may bring improvements. FWIW, I have never seen significant improvements seating bullets out long near the lands for short jumps. IMO this is benchrest twiddlyness that is suited to tight match chambers, though others' mileage may vary. I would assume that your Howa chamber will be large, and to get near the lands you have seated the bullet out almost as far as it will go. This could possibly reduce concentricity and consitent neck tension. I prefer 1x cal of shank seating depth.
Accuracy and consistency is fundamentally down to making sure your reloads are as close to identical as possible.
Well maintained kit and consistent shooting and is taken as read, on a windless day and without heating the barrel.

[phil384]

Once again thanks guys, I've got some more stuff to digest.