.308 Bolt Design Question

[Mike_Honcho]

Regarding (best) bolt designs:

- single ejector 180 from the extractor
- double ejector 180 from the extractor
- double ejector located at top and bottom

Round is fired, extractor claw has control of the rim and imparts tension toward the port as the case is pulled from the chamber. Which bolt design lends itself best to consistent extraction?

Would it be wrong to assume that the dual ejector with ejectors located vertically would hold a distributed tension that would in effect hold the case on the extractor a fraction of a second longer?


TIA

 

[EXTREMEPREJUDICE]

My understanding of the dual ejector design is to provide essentially same amount of force to the ejecting case as a single ejector but using only half the spring force, which allows the ejector spring(s) to last longer. Not really sure about the benefit, my experience is that broken ejector springs are not very common.

Supposedly results in a more consistent ejection angle because it has three points of contact instead of two. I doubt it really has anything to do with timing per se but ...................perhaps?

 

[supercorndogs]

I have seen talk of use of dual ejectors on Remington bolts fitted with aftermarket extractors, to correct the ejection angle, away from the windage the turret and to keep it from falling back in the ejection port.

 

[Mike_Honcho]

And your both talking about exactly what I am as well.

Regarding duality of springs to reduce required ejector tension:
- isn’t the lifecycle on an ejector spring greater than the barrel life?
- if there are two springs, are they equivalent or greater tension than a single ejector?

Regarding ejection angle:
- If the ejector(s) are located at the 180 to the extractor, all forces that are imparted on the case are in the same plane as the port. Conceptually (?) this promotes ejector pressure on the case mouth toward the port, with the extractor acting as a spring assisted pivot point as soon as the bolt unlocks. However, if the ejectors are top and bottom of the bolt, distributed tension is pushed by the ejectors, that are in line with the bore; and there is tension in a separate lateral plane by the extractor.

I am wondering if anyone has any thoughts / data on reliability as a function of those two approaches?