Ethnographic Arms & Armour - View Single Post - A 1548 Nuremberg Dagger-grip Over-and-Under Double Wheellock Pistol

Raf · 11th December 2013, 06:16 PM

On lateral push buttons...
In case anyones confused by this esoteric conversation. With a 'normal ' 2 part sear and prop system two relatively light springs are used to push the release prop under the tail of the primary sear and push the primary sear into the wheel slot .Which is fine except that strength of the primary sear spring is a bit of a compromise . Two weak and it may not push the primary sear in far enough so the secondary prop wont engage . Two strong and it creates extra drag on the internal face of the wheel creating unnecessary friction and wear to the end of the primary sear. The push button allows the spring to be omitted since pressing the button while the wheel is being spanned ensures the sear is always going to fully enter the wheel slot so that the secondary prop will always engage. But will not drag on the face of the wheel when released. In some locks it looks as if the role of the sear spring may actually be reversed and is used to help the sear disengage from the wheel . But if i'm wrong I am sure Michael will correct me. Everybody clear ?
And Michael ; thanks for the brilliant photographs of locks one doesn,t normally get to see. However ; on another thread I suggested that the use of square bolts , (as on these locks ) rather than screws on the major components of some early locks was a distinctive feature that might be indicative of a geographic link or a guide to dateing . Do you have a view on this ?

11th December 2013, 06:16 PM	#25
Raf Member Join Date: Nov 2013 Posts: 238	On lateral push buttons... In case anyones confused by this esoteric conversation. With a 'normal ' 2 part sear and prop system two relatively light springs are used to push the release prop under the tail of the primary sear and push the primary sear into the wheel slot .Which is fine except that strength of the primary sear spring is a bit of a compromise . Two weak and it may not push the primary sear in far enough so the secondary prop wont engage . Two strong and it creates extra drag on the internal face of the wheel creating unnecessary friction and wear to the end of the primary sear. The push button allows the spring to be omitted since pressing the button while the wheel is being spanned ensures the sear is always going to fully enter the wheel slot so that the secondary prop will always engage. But will not drag on the face of the wheel when released. In some locks it looks as if the role of the sear spring may actually be reversed and is used to help the sear disengage from the wheel . But if i'm wrong I am sure Michael will correct me. Everybody clear ? And Michael ; thanks for the brilliant photographs of locks one doesn,t normally get to see. However ; on another thread I suggested that the use of square bolts , (as on these locks ) rather than screws on the major components of some early locks was a distinctive feature that might be indicative of a geographic link or a guide to dateing . Do you have a view on this ? Last edited by Raf; 11th December 2013 at 09:33 PM.