Dutchman
12-04-2019, 07:17 PM
For those of you who hear the term: locking lug set-back. This is what it looks like.
Its caused by the locking lugs on the bolt *pushing* back into the lug race, that part
of the receiver where the bolt lugs cam into place to lock the breech of the rifle.
Pressure pushes back on the bolt face and depending on the metallurgy of the action
the surface of the lug race *gives way*. It compresses the steel into an *imprint* of
the locking lugs. The threaded part of the receiver was milled away to illustrate this
issue. This is where *excessive headspace* comes from. (one of the places).
This action is a 1895 Chilean Mauser that was re-worked to 7.62 Nato.
It literally beat the rifle to death.
https://images45.fotki.com/v1200/photos/4/28344/9895637/DSCF3134-vi.jpg (https://public.fotki.com/dutchman/firearms/dscf3134.html)
https://images41.fotki.com/v608/photos/4/28344/9895637/DSCF3133-vi.jpg (https://public.fotki.com/dutchman/firearms/dscf3133.html)
Its caused by the locking lugs on the bolt *pushing* back into the lug race, that part
of the receiver where the bolt lugs cam into place to lock the breech of the rifle.
Pressure pushes back on the bolt face and depending on the metallurgy of the action
the surface of the lug race *gives way*. It compresses the steel into an *imprint* of
the locking lugs. The threaded part of the receiver was milled away to illustrate this
issue. This is where *excessive headspace* comes from. (one of the places).
This action is a 1895 Chilean Mauser that was re-worked to 7.62 Nato.
It literally beat the rifle to death.
https://images45.fotki.com/v1200/photos/4/28344/9895637/DSCF3134-vi.jpg (https://public.fotki.com/dutchman/firearms/dscf3134.html)
https://images41.fotki.com/v608/photos/4/28344/9895637/DSCF3133-vi.jpg (https://public.fotki.com/dutchman/firearms/dscf3133.html)