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Just to understand ...

The 270 grs Speer / 56grs N140 load I favor shoots apart about about 12-13 cm. Considering Grame Wrights "Theory of Convergence", I would have to increase the mussle velocity to get the individual groups moving down and inwards ... making the gun converge.

Now, iirc the 56 grs N140 load (~2290 fps, ~41900 psi) is close to the max pressure, and even if I increase it up to 60 grs (~2400 fps, ~ 46300 psi) – which is beyond max pressure, the "shooting apart gap" does not close considerably. The above numbers are calculated, not measured - as I don't have a cronograph yet so I have to depend on the results of the program “Quick Load” for speed and pressure.

However, in my understanding, his would mean that I cannot push the 270 grain slug fast enough to get the gun to regulate. It also could mean, that the maximum converging effect is reached already and the gap will not close further, no matter how fast I push the bullets.

Beyond using a heavier bullet - the Nosler 286 Grain partition it will be in the next tests - is there anything I can do to make the gun regulate?

I was thinking about having it re-regulated by Heym or a Heym related gunsmith, but that would mean loosing the current soldering situation: it looks as if the barrels are soldered without thermal stress ... at least the gun shoots it's individual groups no matter which barrel I fire in which order or at which pace ... also it would cost around 600 Euros and 100 rounds …

Any ideas?

Joachim

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