Lock Plate to Snail Bolster "Innies & Outies"

[Majorjoel]

I'd like to start this thread with a note of thanks for all of the help regarding the fitting of the slant breech\tang into the stock of my Hawken project. With some good heat and hammer blows I was able to get the forward hump of the tang to bend downwards and the tail of the tang to rise up enough to lay everything together into a nice tight fit along the slant of the breech plug snug into the stock. "Goot'n'tite" from my limited German vocabulary!   I also peened the upper lip of the breech plug for a perfect tang union with no slop movement whatsoever.  Am now at the lock inletting stage which brings up another issue I'd appreciate some advise on. The bolster snail on this patent breech set up is only about 1\16 of an inch wider than the lock plate. If I am going to use the Ron Long percussion lock that came with the kit, I'm going to have to cut out a section of the upper L\plate rail. There is no "innie" groove in the bolster for the plate to fit under it. Not enough metal there anyway as I mentioned earlier. So, I know how important it is to have this cut-out on the lock plate done for a precise fit. How can I make a pattern for this thing to come together? I have looked at the parts sets for the Hawken rifles in the TOTW catalog and see they supply the same lock (designed by R. Long) for their kits. From reading their info they just mention this lock plate without cut-out is made for the patent breech system. So anyone building this kit would run into my same situation. Sorry to be so long winded, again your help is most appreciated!     Joel

[rich pierce]

This is one reason the Hawken is so complicated.  Here's my approach:  Make sure the snail edges are squared up (90 degrees) to the barrel.  The squared up portion must be wider than the bolster for successful inletting and matching of snail to lock.     

Draw the snail and nipple profile very accurately onto thick card stock.  Place the pattern on the lockplate, moving it around till the cock (hammer if you will) looks like it will strike the nipple squarely.  Trace the cutout onto the lockplate but cut it somewhat undersized- 1/6" wiggle room.  Next closely and tediously fit the lock to the snail with the barrel in a vise until the nipple lines up and you have a good tight fit of snail to lockplate.

That's the easy part, lol.  Now inlet the lock precisely, within .005 of where it belongs.  This is where you'll be happy you really did focus on squaring up the snail.  I mean square for more than the thickness of the bolster.  Because it will then guide the lock inletting perfectly.  If the snail is sort of roundy where the bolster is, there will always be a gap.  You can round the snail from the outside of the bolster outboard later.

[Swampwalker]

I finished up a Hawken earlier this summer - my approach was a little different than Rich's.  I removed all of the innards except the tumbler and the cock from the lock, carefully lines up the correct orientation on the stock, then inlet the lockplate into the stock.  Only then did I rough out the cut for the bolster.  Then it was simply use of transfer color, file and try again to fully seat the bolster into the plate.  This provided for a perfect fit.

[Majorjoel]

Thanks Rich and S-W, this is also the part when I tell you that the lock is already 95% inletted (pre carved stock) so things here will most likely make for complications. Will cross this bridge when I get to it. I have been tossing around the idea of making a pattern out of thin balsa wood and using it to cut out the exact bolster shape. Then transfer it over to the lock plate. Will probably make more than one pattern so when I screw up.......not if will have some in reserve to continue.

[D. Taylor Sapergia]

The snail of the barrel on a Hawken rifle does not have a cut out of the bottom, ala T/C, nor does it protrude past the lock plate ala T/C.  On many late Hawken rifles, the snail is a mere 1/16" past the lock plate.   Some commercial breeches have a snail that protrudes a little more than that.
Since you already have a lock inlet cut in your wood, you'll have to use that as your guide.  Strip the lock but for the tumbler and hammer, and then set the plate into the inlet if it's already finished.  Mark on the plate where the bolster contacts, and using files cut away the bolster of the plate until the plate will fit into the inlet.  It is likely that you'll have to heat and bend the hammer some to align with the nipple.  Most of the originals are bent inward.
Or you can make a new lockplate out of brass or aluminum that fits into your existing inlet, and cut out the area that accommodates the snail, then use that as the pattern to transfer the cut out onto your lockplate.  You can do this as many times as you need to to get it perfect.

[Majorjoel]

From what I am reading about original Hawken rifles, the slant breech style is of the late pattern. (1860-65). With the lock mortice already pretty much a done deal, I will have to put faith in the kit's design for much of this critical alignment to fit properly. I may have a little bit of leaway with the ability to raise the lock upwards a slight hair. The side to side placement is already in stone. When I place the plate into close position with the barrel installed, it appears that the hammer may come into contact with the bolster wall slightly. It is kind of hard to tell this for sure as the plate is well above the final inlet. I am going to install a nipple before going any further and check again. I know that the hammers striker nose will give about the most movement when it is needed. Thanks Taylor!

[BJH]

Be extremely carefull about dressing material from the bottom of the snail especially if this is a L&R breech. The flash hole channel under the nipple has a really thin bottom wall. I got a bad one, and still have the powder tattoo from the bottom of the snail giving away, blowing the lock off the gun and frying my right hand. Wrecking the gun. The bottom wall of the snail was paper thin, And not from filing, I did all my fitting from the lock plate side. Thank God it hapened to me and not my customer.
P.S. I bet you know what brand of patent breech I'll never use again!!!

[T*O*F]

Be extremely carefull about dressing material from the bottom of the snail especially if this is a L&R breech.

I didn't know that L&R made patent breeches, but I would give the same warning to the ones cast by Allan foundry.  Some of them are very thin, expecially the 1" ones.  What scared me most is that guys use them for long range Rigby bullet guns shooting 530 grain bullets.  Unfortunately, there are no alternatives being offered thru todays merchants.

[D. Taylor Sapergia]

I've never seen a breech plug and tang by L & R.

I bought a 1 1/8" Hawken styled plug and tang from TOW years ago, and installed it in Daryl's  69 cal. rifle.  The only filing was to dress it down to the barrel, and polish.  It had a casting void and leaked gas, and we caught it before any damage occurred.  I replaced the breech with another from the same supplier, and have had no further problems.

[Majorjoel]

I appreciate the heads up about the snail wall thinness BJ. I too did not know L&R made breech plugs. I honestly do not have a clue as to the maker of my kits plug. The barrel is by Bill Large. It was breeched when I bought it. From your very bad experience I will make sure no metal is removed from this area! I hadn't previously planned on it but will be sure to remove the plug and inspect it's installation as well as the internal depth's of the bowl. Something that should always be done on any and every build anyway. There is no room for laziness when SAFTEY is an issue!

[Daryl]

The square English breeches should have lots of material.

[D. Taylor Sapergia]

Not necessarily Daryl.  Kip's rook rifle breech failed right in the corner of the thread journal where the drilled passed to connect the cone to the nipple seat.  That drill passes very close to the corner and no metal should be removed, nor the hole enlarged.
And the author of this thread has a Hawken slant breech to deal with.

[T*O*F]

The square English breeches should have lots of material.

They don't, at least on the 1 inch breech.  If you measure down thru the nipple hole, there is about a 16th between it and the flat bottom of the breech.  I had to file the lockplate to fit the breech, rather than take any material off it.

[D. Taylor Sapergia]

Excellent planning ahead, Dave.

[T*O*F]

Taylor,
You can pretty much slap a longrifle together without a lot of thought.  An English gun requires that you spend at least twice as much time thinking as you do working.  Without forethought there are a plethora of things that will bite you in the arse later in the build if you haven't allowed for them early on.

[D. Taylor Sapergia]

's truth.

[Dphariss]

The "events" mentioned above in this post is why things have to be carefully inspected and must be proved with an overload.
The best proof IMO is a standard load followed by a load of a double the service load and 2 patched balls.
I used  piece of 2x8 with a block of 2" screwed to the end, this works best for hooked breeches with no tang. If this interferes with the tang it can be dispensed with or worked around as shown.
I use wood or lead blocks and "C" clamp the barrel to the board. NOTE. Swamped barrels should only be clamped at breech and muzzle to avoid BENDING the barrel.
CLAMP TIGHT. I usually clamp them vent up.
It may be easier to load off the board.
For flint guns a piece of green "cannon fuse" and some powder on the vent will do fine. I staple the fuse in place in this case is runs to small pile of powder with a second pile on the vent. If its windy I have to make adjustments for the priming trying to blow away.




This was a 1 1/8" straight in 58 caliber.   



Dan