lock bolt placement

[The other DWS]

At last I have my barrel and tang  and lock now fully inletted.  I am at the point where I am ready to locate, drill and tap the upper lockbolt. I have about half an inch fore and aft of space to locate the bolt within.  I have seen them located all the way from behind the cock to almost touching the "fence".  Are the stylistic reasons or functional reasons why one particular location would be desirable than another.

if it matters the lock is the Davis "early english" roundfaced with the light cast-in engraving

[James Rogers]

The better original English guns I have seen had a blind hole in the bolster. Second choice for me would be through and behind the cock at half bent. You can do this with a Chambers but I do not believe you can get enough bolster on your particular lock.
I am thinking the Bumford trade gun with vine painting comes thru in front of the cock and there are American made pieces that have that.
What are you making?

[Swampwalker]

Leave the lock in the stock and remove the barrel.  Scribe across the bolster where the breech of the barrel comes too.  Anywhere on the bolster behind this scribe is fine.  I usually center them vertically on the bolster just behind the breech, with the screw extending through a hole through the breech plug.  The only stylistic issues would be if you were copying a specific rifle.  I'm not aware of any significant regional differences in where they were placed.

[Dr. Tim-Boone]

Be aware that you want to make sure the head of the lock bolt is below the top edge of the sideplate molding  .. Sometime the bolt will slant down slightly from where it istapped into the lock bolster (Slanted hole too obviously....  So depending on the taper on the sidepanel and how fast it drops from the highest point down to the wrist you may want the lock bolt a little forward..under the highest point of the sidepanel.....  measure twice drill once 

[The other DWS]

"measure twice drill once"   

amen,  Amen,  and AMEN!!!!!!!    a critical lesson learned in this game, thankfully early.

also  "if in the slightest doubt, ask lots of questions"  followed by  "be patient, wait for the answers before proceeding"

[Jim Kibler]

You may want to consider your sideplate design.  This may help you decide where to place the bolt. 

[JTR]

I'm probably wrong, but wouldn't you want to locate, if not inlet your side plate, before drilling the hole? Assuming you're using a two bolt side plate.

John

[rich pierce]

Might be custom designing the sideplate.  I have a feeling that on many originals they used templates or uniform castings for the sideplate though.  Certainly the case for trade guns etc.  So probably they put the rear bolt where it belonged on the sidplate and jiggled the lock and sideplate relationship to the breech, if you follow.

[Keb]

I had to be pretty careful on my last rifle because of using a Chambers Early lock & a side plate with the mounting holes already in it. There is a limited amount of room in front of the main spring so I  actually put the front screw in 1st then tapped & drilled the stock to locate the side plate. I then drilled the rear screw location thru the stock. It barely caught the edge of the tang bolster.

[Jim Kibler]

I'm probably wrong, but wouldn't you want to locate, if not inlet your side plate, before drilling the hole? Assuming you're using a two bolt side plate.

John

I've never used a pre-made commercial sideplates, so it's simple to install the bolts and then make a sideplate to fit the panel and bolt spacing.  It seems likely that during the 18th century a standard pattern was cast and consistently used on multiple guns, even with varying lock sizes.  This is likely why sometimes sideplates are seen mounted at odd angles. 

[James Rogers]

I have heard that some of the locks imported here came with the nails and the plates were threaded and ready to go. Is this true?

[Jim Kibler]

Gary Brumfield made mention of this a short while ago.  A search will probably find his post.  As to fitting cast sideplates to a lock with a pre-determined bolt spacing, perhaps the front extension of the sideplate was cast from a pattern where this was made intentionally long, thus allowing fitting to varying sized locks.  This can be seen on the hunting scene English sideplate used by Richards and Griffin.  The same pattern was used on a rifle sized lock and a pistol sized lock.  The area directly behind the front lock screw was produced such that it could be shortened to fit the smaller lock without disturbing the design.

[The other DWS]

{got sidetracked and forgot to "send" earlier}

very good points, and so more waiting and thinking and measuring.
I have ordered two more sideplates the other day,   found out that my 1st purchase would be too small. found two that should be properly sized but with different appearances.

but I can calculate and measure out a "box" on the plate side of the stock that the bolt could go in. that'll help when the sideplates get here.

[Pete G.]

{got sidetracked and forgot to "send" earlier}

very good points, and so more waiting and thinking and measuring.
I have ordered two more sideplates the other day,   found out that my 1st purchase would be too small. found two that should be properly sized but with different appearances.

but I can calculate and measure out a "box" on the plate side of the stock that the bolt could go in. that'll help when the sideplates get here.

Cut your own sideplate to fit your own gun.

[Acer Saccharum]

If your main lock bolt is too close to the breech, you don't have much artistic license too shape the breech wood in the way you like. Move that screw back as far as you can so you can shape the sideplate area around the main lock bolt to your heart's desire.

This view shows the lock bolt too close to the breech. While it appears to work, visually, I'd like to see a little more wood between screw head and woo.


While this gun works, I'd still like a little more wood betw the screw head and breech. Why? I would allow a little more rounding betw screw and breech wood.

[bgf]

Acer,
I agree with that for what very little that is worth, and that picture makes the problem easy to see (although I like the rifle anyway).  Also, am I wrong in wanting to put the bolt farther back in order to use an open notch instead of hole through the tang bolster?  I really like it that way; pulling a lock bolt to pull the barrel (or breaking the stock when you forget) seems clumsy to me.  I seem to recall recent pictures of originals that were notched.

[Acer Saccharum]

Plenty of original tangs are notched. More often than a hole thru the tang.

I love a screw with a large head, and that means I need real estate behind the breech. I usually build a rifle and don't realize that I need to think ahead to get the lock screws where I want them. I think this might be my third rifle where I know what I need to do, but have not thought of it until after it's too late. Comes with the territory, I guess. Roger Fisher will tell ya this is so.

[AndyThomas]

bgf,
You'll still have to pull the rear bolt when it's notched. You need a hooked breech.

Swamp,
I determine where I want the bolt head to be and drill from both sides.

Also, I put the rear bolt hole at the rear of the lock bolster for the reasons Acer just made.

On the old guns, the front bolt is centered vertically on the lock, perhaps because the lock came that way, as was stated. I think we tend to use smaller diameter barrels than the locks were originally designed for, which sometimes puts a centered bolt hole too low, i.e., through the ramrod hole. If you place the lock so that the centered hole goes through the web between the bbl and RR hole, then the lock is canted too much (as some old guns are!). Things to consider!

Nobody said this stuff was easy.

Andy

[Swampwalker]

Andy, I don't really understand your emphasis; that's a given!
With the rear (upper?) lock bolt, you actually have a fair amout of latitude in placement to meet your design goals.  On the rifle which inspired my current build, the upper lock bolt is placed very far back on the bolster, which definitely changes the shape & proportions of the sideplate.  Presumably, he placed it there to avoid the breechplug, or to fit an existing sideplate as has been suggested.

[The other DWS]

I see that a number of rifles have the front hole too low and that kicks the tail of the sideplate up rather awkwardly, At least to my taste. 

IN my specific case I am just using the one bolt. The front lock-bolt will be dummied on both sides with a cutoff threaded stub in the plate notched on the inside to catch a pin holding the nose of the lock-plate in place.   That'll allow me to align the sideplate for the best visual line
I'm not sure yet how I'll do the front bolt on the side plate side.  I might cheat and put a glued in machine-screw threaded insert in the wood for it to screw into. or I could cut/grind down a wood screw I suppose

[Longknife]

I have a two  rifles made by highly regarded contemp. makers and they both used only one screw to secure the lock with the foreward one shortened and screwed into the wood. I drilled and tapped one and installed the foreward bolt, on the other I was worried about clearance issues and left it alone (THATS how her got the profile so thin!!!)  I believe the threads are 10-24 and they hold good in the wood....Ed

[bgf]

bgf,
You'll still have to pull the rear bolt when it's notched. You need a hooked breech.
...
Andy

Andy,
Maybe I should pull the rear bolt first, but I never have.  Now you have me wondering what I'm doing wrong.  The hooked breech is a further convenience, certainly -- you don't even need to pull the tang bolt.

[D. Taylor Sapergia]

If you use commercially cast or cut side plates, you must be very careful in their selection so that lock bolt placement is not a problem.  It is far easier to put the lock bolts where there are best, and then make a sideplate to fit...everything is a lot happier.  Side plates , made out of 1/8" brass sheet are fun and easy to make, and add a lot to the hand made appeal of the rifle.
I like to get the rear lock bolt as far back, and low, in the plate's bolster as I can.  Even so, almost always, I have to drill though the breech plug lug.  I make that hole with lots of clearance so as not to have conflict between the barrel and the lock bolt.  Often, the hole gets opened up in the back, but the lock always comes off the rifle first for cleaning anyway, so that is not an issue, for me.  I agree, again, with Tom...lock bolts with large heads are lovely.  A 1/4" x 20 tpi carriage bolt makes into a great lock bolt, turned down to 3/16" and threaded 10 x 24.  Before I had a lathe, I used my electric drill clamped in the bench vise, and a file to make 'em.

[The other DWS]

BGF,  I wonder if he is referring to the tang bolt or screw needing to be removed to remove the barrel, unless you have a "hooked breech"  If you have a breechplug lug notched out for complete clearance of the rear lock bolt it should not interfere with removing the barrel once the tang screw/bolt and the pins or keys are removed-----I think

[AndyThomas]

bgf,
You'll still have to pull the rear bolt when it's notched. You need a hooked breech.
...
Andy

Andy,
Maybe I should pull the rear bolt first, but I never have.  Now you have me wondering what I'm doing wrong.  The hooked breech is a further convenience, certainly -- you don't even need to pull the tang bolt.

What I meant was that the barrel must be removed straight up (I assume it's a tapered & flared bbl, perhaps a wrong assumption). I'm also assuming the notch is toward the back of the bolster (again, maybe a wrong assumption). If this is the case (on my guns it is) then the rear bolt must be removed.

You must have the notch going down, so the bolt isn't captured.

Andy