Alexander Henry back-action percussion cap lock

[Naphtali]

Blackley and Son sells Alexander Henry back-action percussion cap lock castings' sets - that is, parts "as cast," without finish machine work, without heat treat (http://www.blackleyandson.com/acatalog/Lock_Sets_Percussion_Rifle.html near the bottom). I have zero experience with their product, and no one I know has experience either.

1. Is this lock appropriate for an English-style Big Bore sporting rifle, based upon 1.25-inch O.D. barrels? I have located a bazillion photographs of such rifles having bar-action locks, but none having back-action. Photographs of Alexander Henry bar-action sporting rifles show attractive rifles, to my eyes. And photographs of back-action locks I have seen on Engish/Scottish/Irish sporting rifles, circa 1870-1900, are comparably attractive. But these are cartridge guns.

2. Please describe the quality of their raw castings - finish/RMS, precision of castings to finished part, materials used for non-springs - and degree of difficulty metamorphosing their castings to Alexander Henry lock. My experience the The Rifle Shoppe's "as cast" parts has me concerned about circling the drain of an endless job.

4. In an earlier query of mine regarding effectiveness of Pedersoli's Mortimer flintlock "stalking safety," the consensus was parts associated with that safety were flimsy. Does this lock set suffer a similar problem?

4. What finishes are appropriate for such a lock, and rifle? I suspect color case hardening, or pack hardening would be okay. But what others, if any?

[T*O*F]

Did you read the description.  That lock set is for a falling block cartridge rifle, not a muzzleloader.

[Naphtali]

Yes, I read that. I did not, do not understand what difference there might be, except perhaps a tumbler that causes the hammer to rebound?

[JTR]

That's also a left side lock isn't it?

I ordered some flintlock parts from them some time ago. The parts are very nice castings, excellent, probably some of the best, but it took Foooooor eeeeever to get them! I mean like close to 1 1/2 years.
Maybe he's improved his shipping since then, but I've never re-orderd to find out.

John 

[Feltwad]

I receive all my castings from Blackley, all are made using the lost wax method and took from the originals .Yes I live in the UK but if he has them in stock I receive them within 3 days .The only time I have too wait is when  I have just missed a cast. For the quality of his castings to me they are good .
Feltwad

[Naphtali]

While I am uncertain whether the lock is made right-handed, it is made left-handed - as am I.

That's also a left side lock isn't it?

I ordered some flintlock parts from them some time ago. The parts are very nice castings, excellent, probably some of the best, but it took Foooooor eeeeever to get them! I mean like close to 1 1/2 years.
Maybe he's improved his shipping since then, but I've never re-orderd to find out.

John 

[Acer Saccharum]

Old back action shotgun locks can be had. Some are total junk, but others are quite nice. You can switch the hammer to one you like.

Also, L&R makes a back-action perc lock, quite nice.

Building a lock from castings is a real chore. It took me several locks to 'get it'. I always buy an off-the-shelf lock and modify it whenever I can.

[westbj2]

"1. Is this lock appropriate for an English-style Big Bore sporting rifle?"
A back action lock on a 1840-60 percussion sporting rifle would be somewhat unusual, as conventional front action locks are by far most commonly seen.  With that said, because of the 1 1/4" inch barrel you mention, it happens that the dimensions would come close (depending on bolster/breech) to allowing you to use this lock.  But there are some considerations.

If you look closely at the pictures of the Blackley parts, notice the sear.  It has the "offset" or "step" also found on the lockplate, bridal, mainspring and sear spring of this lock.  This "offset" allows the architectural transition from an action width of 1.600" down to 1.150" width of the wrist. 

A picture of an original lock from the top:



Here is a better look at the "crooked" internals on a original and a new lock



The Blackley hammer casting would require more effort and work to adapt to a 'percussion conversion' than it would be worth.  You would have to make a new hammer because the angles and dimensions are just too far off.

By the way, the Alex Henry locks are not rebounding, rather the forward movement of the hammer is stopped as the flat on the bottom of the hammer throat comes in contact with the top action corner.  So, once again you could make a new hammer which stops the lock upon hammer contact with the nipple.,



As to making one of these locks from castings, Tom's advice is sound.  It would be difficult.  The tolerances required are quite close.....more so than a conventional lock.

Jim

[Bob Roller]

There was an article in a magazine sometime back,maybe the Double Gun Journal or maybe "Rifle Magazine" about a superb Whitworth with a back action lock and I saw one at Friendship in the museum that had a back action lock. I think this was in 2000 when the display was dedicated to English Target Rifles. Tom Schiffer knows for sure.
They may be rare but they are not unknown,
I will guess at the name of theauthor of the article about his Whitworth with the back action lock and say Ross Siefried or maybe Siegfried. He killed a moose with it as I recall.

Bob Roller

[Bob Roller]

One problem I have encountered with "kits"reproduced from antique locks is that the antique lock itself was made to minimum dimensions and the parts reproduced by using them as masters for moulds are below minimum dimensions due t shrinkage. .
I think these kits are more useful for restoring relics than for today's shooter/hunter. I use cast plates,hammers,cocks and frizzens but will have nothing to do with the often flimsy internal parts made from antique locks. The American made locks from Jim Chambers and others are designed to be used with parts made in moulds that compensate for shrinkage
and seem to work quite well,much better now than ever as a matter of fact.

Bob Roller

[Naphtali]

Many thanks, guys. The castings are unsatisfactory for my intended purpose.

One facet of Blackley's blurb AND mentioned among replies is that castings - I believe everyone means investment casting DIES - are made from original parts. As a rule, this is a recipe for cast parts that look like the original while castings' dimensions are off. How much off would depend upon part's shape. And to render the potential yet more bizarre, materials used for castings could render parts smaller than original - or larger. Some stainless steels cast larger than some alloy steels - for example, Armco 17-4PH casting alloy drops 1.4 percent larger than AISI 6150. And 17-4's casting alloy has different chemistry from its bar stock, to compensate for changes/migration of elements during the melt.

I have wondered for years whether this "creating dies from original part" is the reason why TRS parts I obtained years ago were such a nightmare. . . . I have no idea whether any problem remains.

[Acer Saccharum]

Usually epoxy hard tooling is made from original parts. Then Wax is injected into the mold (wax shrinks). Then a ceramic shell mold is made with the waxes, burned out, then metal poured in. Then the metal shrinks.

So you have two shrinks to deal with, wax and steel, or brass.

[Jim Kibler]

When molds are made from original parts, silicon rubber is often the material of choice.  Molds made from this material are much less labor intensive and costly to create.  Hard molds made with epoxy and aluminum shells often require cores and sliders etc. for all the complex geometry to be cast.  Silicon rubber is flexible enough that mold relief often isn't necessary.  There is no concern with any parts becoming larger in this process with alloys used on longrifles.

[Acer Saccharum]

I found that using silicone when I use high enough pressure to fill the parts to reduce sinking in heavy sections, the mold often blows out. Then if you don't use enough pressure the parts can sink.

[Jim Kibler]

I started by making hard aluminum shelled, epoxy filled molds.  These were produced from masters I made.  In making an english fowling piece with a fair amount of relief work, I opted to try silicon rubber molds.  These were made with a plywood shell.  I was very happy with the results I got from the silicon rubber.  It's much simpler, less time consuming and costly.  For relatively limited runs, I think this is usually the best choice.  It is likely not quite as accurate, but for gun hardware this isn't a problem.  I did find that I had to run lower injection pressure and higher temperature as compared to the epoxy tooling.  I've cast standard fowling piece hardware and haven't noticed suck or shrinkage problems, but can imagine it being a problem on very thick sections.  The good thing is in an area where wax shrinkage is a problem a little additional wax can usually be built up by hand.  A touch more finish work, but probably not a big deal on small run projects.  I think it's a safe bet that most of the parts reproduced from original work are done so by investment casting with silicon molds.

[Bob Roller]

I posted a while back about the late Lynton mcKenzie telling me about some Swiss made dies to produce lock parts for the British "4 pin locks"but the parts were costly and the VERY limited interest in precision cast parts was killed the whole idea. My own preference is to make the whole mechanism from bar stock and use a cast hammer and sometimes,a cast lock plate.
I don't know if the Swiss made dies are still extant or were scrapped or what their fate was.

Bob Roller

[gunsports]

If you are looking to build a large caliber Englsih sporting rifle, this is probably what you should look at. This is an original from a half stock 10 bore ESR. It is a brute of a gun. The lock is all of 5 1/2" in length and fits to a breech that is just on 1 1/2" in width. Unfortunately, the barrel is shot all to $#*!; but I plan to rebuild this rifle with a 12 bore 1:104 Forsyth style barrel for ball.