doublegunshop.com - home Forums General Discussion DoubleGun BBS @ doublegunshop.com Chips/cracks at rear of locks?

Is there any way to stop the cracks/chips you'll often see at the rear of sidelocks/sideplated guns? It's my understanding that they often result from a stock that is inletted too tight.

The majority of guns I have seen that have been used regularly show signs of fine cracks or chips in this area. I've seen it on sideplated guns right up to Purdeys. I have a couple just starting on my own guns and would like to rectify it now as opposed to just letting the stock split a few years from now.

Thanks..

Chips and cracks are caused usually by the movement of the metal against the wood. As a stockmaker, it is poor workmanship to leave gaps around the metalwork on a sidelock. One can make the fit close enough that the locks don't bind on the wood.

After much recoil/wood compression the fit becomes too tight. It may take a long time or a short time depending on the way the stocker inletted the action into the wood and the wood pore structure itself.

Your question about how to stop it is not an easy one. If the wood compression is sever, one must stop the compression. Epoxy can and has been used to stop this process. Of course there must not be any oil in the inletting in order for the glue to adhere to the wood. You fix the cracks at this time too.

Sometimes the easy fix is to just releave the stress areas. Scapers, knives, chisels, or sandpaper have been used to accomplish this action. In my opinion though, this is not a solution to the problem. It is is only a bandaid. In my experience cracks and chips are a symptom of the problem that must be addressed not the cause. Ok, poor inletting doesn't help either.

On a LC Smith in particular, it's been my experience that the cracks originate at the head of the stock about 3" forward of where they show at the back of the locks. By the time they show at the back of the lockplate, they are fairly long. I've used carbon fiber cloth to reinforce the head and under the lockplates of the stock (in the trigger slot).

Check this and the next 4 pics
http://www.picturetrail.com/gallery/view...amp;offset=1300

Interesting thread. I think most cracks behind the lockplates are caused by setback of the action into the wood. Some actions have more bearing surface designed in the head of the stock, and others don't. If you're around double guns for a while you'll get to know which are more prone to cracking. Once in a while someone will write that cracks are caused by old wood that's tightened around well inletted lock plates. While I suppose that might happen once in a great while, I really don't buy that explanation as a general rule. Take a look at some Manton or W&S flintlock and percussion double guns. All have very tightly inletted locks. Another example is the excellent Syracuse Lefevers circa 1890's. You'll rarely see cracks behind the tightly fitted lockplates. In both examples, the wood is pretty dry by now!

Too much oil squirted into the firing pin holes, running into the wood and softening it? That happens with all makes including Lefevers and Holland & Hollands. If a gun has enough bearing surface in the head, the action won't set back as much as one with lesser bearing area.

Personally I think that glassing a classic sideplate gun to prevent it from splitting is like pop riveting some galvanized sheet metal onto the fenders of a 1933 Packard coupe so they don't start stress cracking if you want to drive it a lot. If I have a shooter-grade gun that is already cracked, the glass route might make some sense; but if it's a collector grade gun I'd sell it off and get another classic double gun I can shoot as much as I want without worrying about getting cracks started. In fact I have done that. IMO of course. Silvers

I think I may need to post some photos to get an assessment. All I know is that both of my Garbi's are showing minor signs. You couldn't fit a piece of paper between the locks and wood but the locks come out easily enough so I don't get the sense that they're binding. They're all copies of an H & H seven pin so I don't know if they're more prone surface area wise than anything else.

All I do know is that they shoot great and are expensive and I have no intentions of selling them. I'll take whatever steps I can to avoid having a real problem later.