Donuts??

[NorCalMikie]

If a bullet is seated the "full length" of the case neck, down to the shoulder/neck junction will you still get donuts??

 

[tightneck]

Where you seat a bullet in the neck will not cause the forming of a donut. Donuts are created from necking brass up or down to different calibers and from improper neck turning. Even with proper neck turning donuts will form after multiple firings of the same brass. Brass grows in length with every shot and resizing procedure hence the need for a case trimmer. The brass that is being trimmed off is coming from the shoulder of the case which is thicker than the neks that have been turned. That thicker brass slowly finds its way to the neck creating a donut also. Now if you have donuts in your case necks, then seating a bullet below the donut line will actually push the donut to the outside of the neck creating a bulge in the neck. If that bulge is bigger than the neck diameter of your chamber, then you may have big problems. You will certainly have accuracy problems and could create very dangerous chamber pressures. The easiest way to avoid this is to always seat your bullets above the neck/shoulder junction and not worry about that damn donut.

 

[Preacher]

The only other real problem of those darned dougnuts is the restriction they cause.
They restrict NASCAR carbs with restrictor plates between the base of the carb and the intake manifold to slow em down.
So I figure the doughnuts are causing the same things by creating a tighter hole to flow all that powder plasma through.

 

[tightneck]

Preacher, in theory I agree 100% but I cant seem to see any difference at the target or on the chronograph.

 

[Preacher]

Tight neck,
I never did either but the thought is still there, and I like to contemplate about such things as that seeing it's been to darned wet to shoot around here.

 

[tightneck]

It's funny, actually I often find myself contemplating whether deburring flasholes or reaming primer pockets, or donuts or whatever is causing those damn fliers. But in the end, I'm pretty sure that the NUT behind the bolt is whats causing them