doublegunshop.com - home Forums General Discussion DoubleGun BBS @ doublegunshop.com 5 pin, vs 7 pin v 9 pin sidelock--discusson

It took my V-C sidelock pigeon gun to an English trained gunmith and he said it was a "9 pin" sidelock. I had been told it was a 7 pin and you did not count the hammer axle and the pin that holds the main spring.

I have always been confused on this issue, especially the 7 pin vs the 9 pin discussion. I understand that the 5 pin has coil springs for intercepting sears and the 7 pin has leaf springs but how do know which pins to count to determine the correct type action?

Confused in Missouri---

Me too...Geo

Hello Paul,

maybe some help here???:

http://www.youtube.com/watch?v=vO15tbeaWGg

Regards,
Wolfgang

So...the two extra holes in the lockplate are for the screw that secures the top of the leaf spring and pin at the fold?

Gunwolf I have seen Dan Moore's presentation many times and it does not help. I need for someone to approach it from the outside of the lock plate tell me which pins count on the 7 pin vs 9 pin discussion.

Any help appreciated.

The only pins(screw posts)that count are the ones that hold something. That would be for a bridle, sear, sear spring (if any), mainspring, intercepting sear. Technically the sear post and tumblers are axles.

The 7 pin sidelock is for reference sake similar to the Holland and Holland bar action lock which is supposedly the most copied lock in the world. If you count all the pins including the tumbler and the mainspring pin, you come up with 9 pins. Most back action locks I have seen have less than 9, but some have that many pins. I think as a general rule, and barring the pinless lock, the less pins the less sophisticated the lock.....or more primitive the lock. For example, the L. C. Smith lock, which is a 4 pin lock (maybe less if you don't count the tumbler) is a back action lock that lacks intercepting safety sears and I think most would agree, more primitive than a Holland lock, yet probably just as functional. At least this is the way I look at your question which I have pondered myself.

Buzz, is there any reference books that would help me understand better the pin question? I think some people count the pins differently and I would like to know the correct way to determine what lock arrangement that I am looking at. Any more help from anyone would be appreciated.

This is an L.C. Smith bar action 6 pin lock showing pins and or axles.

Zabala Derby 6 pin lock

Zabala Derby showing pins/axels. Note the 6th pin is a dummy pin. Since this has a coil mainspring, the 6th pin was most likely used for a leaf mainspring.

You can also see how the hammer screw pivots in the bridle and has an indexing to show fired and unfired position.

Most screw pins have a polished,rounded end to make them look like pins.

One of the most coveted sidelock actions is the Lancaster 12/20, invented by William Baker. It has only 8 pins. Is it more or less worthy than a 9 pin sidelock?

Speaking of Baker, his other superbly simple sidelock has only three pins, but it makes up in robustness and simplicity what it lacks in pins.

In engineering it is considered an advance to develop a device that works with fewer parts. Perhaps we should keep this in mind.

The Dickson Round Action has no visible external pins anywhere. One reason people like it is because it bypasses these sort of dilemmas.