Split Necks & Accuracy

[gbw]

Recently at a range I found several .30-06 cases with split necks - I believe these were fired by a member through a Garand.

I never really thought about it much - does a split neck affect accuracy in a rifle? Why, and by how much roughly?

Seems it wouldn't matter much, especially if it splits after the bullet is released. But I know nothing of the behavior physics of cartridges & ballistics.

 

[WestKentucky]

If anything it SHOULD drop pressure a bit if gas escapes before bullet has left the barrel. Full power loads swell to chamber so it would seal off so no change. If a light load is used it would be of a bigger deal as the case wouldn't seal to the chamber and hot gas will escape towards the rear around the rupturing case. As far as accuracy goes, that round may hit a bit low. The next few May show exaggerated flinching as the debris in the action will slightly slow it down increasing lock time and therefore flinch will show more. Flinch will be really exaggerated if you have powder burns on your hands and face.