doublegunshop.com - home Forums General Discussion DoubleGun BBS @ doublegunshop.com Intercepting Sears

All,

Grateful for comment on the worth of intercepting sears. Tried to raise the issue in the long discussion Ken Hurst started on making a modern version of the Lefever. Poster G.P. argued for possibly considering a hammer block as an safety-enhancing alternative. Both he and I recognize that adding intercepting sears would be a change to the basic Lefever design. But it could be a salutory change depending on the views heard and, of course, on the extra costs.

Of especial value would be comment from gunsmiths and doublegun fundi.

Regards, Tim

An intercepting safety is another line of defence agains accidental discharge.

I think it matters little whether this is an intercepting safety sear, like those used in Boss and Purdey sidelocks or an intercepting safety bolt, like in some Scott guns.

The point is - what is there to stop the tumbler hitting the striker in the event that the sear/bent connection should fail or be jolted out whithout the trigger being pulled.

If you don't have an intercepting safety, the gun WILL fire if the sear is jolted out of the bent, with an intercepting safety, it will be prevented from so doing.

Well made locks accidentally discharge rarely to the point of never, but that extra insurance has to be credited as a better system in my opinion.

Tim,

Hammer block is not a bad or new idea. Bakers had hammer blocks about 100 years ago. Take a look at the design. It may work in your application.

Phil

Personally, I have always felt the hammer block as used on the American Bakers (other than the batavia line) was about the best of all systems. With mechanical connections & the safety engaged there is simply not much chance of it moving. I have also felt an intercepting sear should work somehow in a different direction than the primary sear, less a blow sufficient to "Jar Off" the sear also jar the interceptor out of engagement position. The Lefever design with it's sear engagement on the outer periphery of the hammer is less subject to jar off than those engaging close to the axle. Another very good sear design in my opinion is one found on a J P Sauer/VL&D sidelock ca 1900 I own. This sear also engages on the outer periphery, but the sear itself is mounted vertical & it's pivot is near center. Thus it does not have a "Heavy End" to be so easily moved by a blow.

Don't change the design, it’s a Lefever keep it exactly as it was designed. There is no such thing as a mechanical safety, all mechanical safeties fail. The ONLY safety that exists is to keep at all times the barrels pointed in a safe direction. But what does that mean, it means don't run and fall in a gopher hole cause your all excited about seeing a bird, spilling your gun on the ground like a fool. It means while your hunting you move slow, and I mean as slow as molasses in winter time, know where at all times to place your feet and approach all and I mean all situations, which takes experience, where it could possibly be dangerous and then move even slower.
All the best

Miller,
Could you elaborate on advantage of sear engagement on the outer periphery of the hammer as it pertains to reduced probability of disengaging accidentally?

It would be tough to come up wit a more simple, foolproof design then one similar to the Baker hammerblock system. A true, English pattern intercepting sear design requires bunches of parts, very delicately fitted up, and, might be very difficult to engineer into the Lefever cocking hook, boxlock design-remember, the Lefever only looks like a sidelock, Tim. It is a boxlock.
The actual "need" for a mechanism to prevent accidental firing, on a limited production bird and clays use double, is likely slim to none. I'd like to believe the eventual users will be a thoughtful lot. Excepting a V grade Darne I once owned, none of my past guns has had them, and I've never had the need.
Best,
Ted

Treblig,
While retaining a vintage design is admirable and your advice on hunting and gun handling well meaning and probably practicle to adhere in many situations, hunting in itself often pushes the physical limits of hunters and events often occur which can lead to potentially unsafe situations. There are undoubtedly stories all here can tell. Of course, one can point out the faults of the hunters/gunhandlers in each situation cited. However, the fact remains; guns pointing in unsafe directions or being dropped, mishandled, or an AD happens and it happens relatively frequently.

Managing risk is part of the biz I'm in. We can't eliminate it but we evaluate risk using all available good tools and information. Service history is a big one. Regardless of how we recommend a product be operated, service history is the reality. It cannot be ignored where lives are at stake. If we instruct operators to use our product a certain way, yet there are numerous examples of operators using it another way where a hazard is created, if the consequences and probabilities of occurrence are high, we explore a solution that will reduce the risk to an acceptable level.

It's a matter of deciding if the Lefever design is within an acceptable risk and if further reduction in risk is needed or desirable balanced against the cost(effort, time, money, etc.).

This discussion is a good one, IMO. Now is the time to have these discussions and to see if practicable design solutions can reduce risk that is known in the proposed design.

Chuck, I think Miller just meant that sear-bent contact points nearer the axle require (create) higher engagement forces to resist a given spring torque, so are more prone to slip / break / whatever if something bad, or a combo of bads develops (like wear, etc.).

Intercepting sears are usually, if not only, seen on sidelocks. The sear/hammer design and relationship on a Lefever side-plate Syracuse action is so different from the typical sidelock action, trying to add intercepting sears would be as useful as adding air conditioning to a motorcycle and probably more difficult. Has anyone ever heard of a Lefever jarring loose and firing accidentally. Lefever claimed it couldn't happen. That's certainly more believable than the claim of a continuous tapered choke, from chamber to muzzle.
If you're going to build a Lefever reproduction, reproduce the Lefever design, for Petes's sake.