what is average pull/DRAW- poundage measured-when cocking lock hammer?

[CHARLY]

   Has anyone  tried to calibrate the load /effort  required to load a std lock hammer?

what is the acceptable  poundage or ft /lbs ---or tension on mainspring of a average long rifle
lock ---that is required ---to load the hammer?

I used a rather primitive fishing scale--recorded a shaky 27 -30 lbs average

is that too much ?----if so ---what is correct tension ?

appreciate any data ---

[Acer Saccharum]

With flintlocks, there is no standard.

A strong main must be balanced by a strong frizzen spring. Locks are all about balance. Strong springs usually equal reliable ignition, short flint life.

A well set up lock will be difficult to pull back at the beginning of the stroke, and by the time the hammer gets to full-cock, the pull is much lighter. This is because the tip of the main spring gets closer to the center of pivot as the tumbler is rotated back.

[Hungry Horse]

Charly;

  I am afraid you are severely overthinking this issue. Stong springs for flinters, both main, and frizzen, are the best. For percussions, if it consistently busts the cap, you're good to go.

              Hungry Horse

[Ky-Flinter]

Charly,

I think 27 to 30 pounds is too much.  I used an antique scale on a new Siler lock and it went to full cock with about 14 pounds of pull.  I must qualify that by saying that I'm not sure of the accuracy of this old scale.

-Ron

[E.vonAschwege]

I too think you're overthinking this a bit.  Heavy springs shouldn't jar or torque the gun at all if the mainspring is balanced with the frizzen (geometry plays a role to, but that's a different story).   Acer is right that balance is what is important between the mainspring and frizzen spring.  Also consider that a well polished, tuned, and case hardened lockplate will require less effort to cock than one that has rough bearing surfaces and the steel left in its mild state. 
-Eric

[Pete G.]

It depends on where you are connecting the hammer to the scale and the angle of the pull. The closer to the hammer pivot the more force required, the further from the pivot the less force required. If you vary the angle of the pull from anything other than perpendicular you will get yet another value.

Since you can get various measurements with no change to the mechanism itself it means that the recorded weight is essentially meaningless

[JTR]

I checked a new large Siler and on my new fish scale, and it required 15 or 16 pounds to pull the hammer back to full cock.
A new small Siler took 8 pounds to half cock and 11 pounds to full cock.
A 35 year old Durs Egg lock took 8 pounds to half cock and 10 pounds to full cock.
And an original fine condition Baker flint lock took 15 pounds to half cock, but only 11 to go from there to full cock.

The scale hook was on the top jaw screw for the test, and I kept the scale pull perpendicular to the axis of the hammer.

As for 'feel' the old Baker was by far the best. The Durs Egg was very smooth. The Silers, both so-so.

I also checked a couple of my original guns for 'feel', though didn't measure them with the scale. Both took more force to pull to half cock, than from half cock to full cock. Like the Baker lock did. I've heard this before from a number of guys and I'm supposing this has to do with better geometry/spring quality in the old locks, than with the new ones.

John

[chris laubach]

I checked a new large Siler and on my new fish scale, and it required 15 or 16 pounds to pull the hammer back to full cock.
A new small Siler took 8 pounds to half cock and 11 pounds to full cock.
A 35 year old Durs Egg lock took 8 pounds to half cock and 10 pounds to full cock.
And an original fine condition Baker flint lock took 15 pounds to half cock, but only 11 to go from there to full cock.

The scale hook was on the top jaw screw for the test, and I kept the scale pull perpendicular to the axis of the hammer.

As for 'feel' the old Baker was by far the best. The Durs Egg was very smooth. The Silers, both so-so.

I also checked a couple of my original guns for 'feel', though didn't measure them with the scale. Both took more force to pull to half cock, than from half cock to full cock. Like the Baker lock did. I've heard this before from a number of guys and I'm supposing this has to do with better geometry/spring quality in the old locks, than with the new ones.

John

You are correct.....On a lot of the good quality English and German Locks that I have studied have what I would consider proper geometry....as the mainspring gets closer to the center of the pivot point of the tumbler it becomes easier to cock.

C. Laubach

[Dphariss]

   Has anyone  tried to calibrate the load /effort  required to load a std lock hammer?

what is the acceptable  poundage or ft /lbs ---or tension on mainspring of a average long rifle
lock ---that is required ---to load the hammer?

I used a rather primitive fishing scale--recorded a shaky 27 -30 lbs average

is that too much ?----if so ---what is correct tension ?

appreciate any data ---

As others have mentioned.
On many of the locks made in England (at least) and especially the late locks like Mantons etc with a linked mainspring the initial pull is much harder than it is nearing full cock due to the "arm" of the lever being shortened as the tumbler rotates if the link-tumbler-mainspring are in the proper relation to each other. At full cock this reduced pressure reduced wear on the sear and the tumbler also made it easier to get a nice trigger release. Most locks  found on Kentucky rifles were not so well engineered.
The pressure is really not that important on a flintlock. If it functions well and the cock fall is not too slow then the mainspring strength is probably proper.
I never bothered to measure it but I am sure my Manton design lock requires a pretty hefty pull to come to 1/2 cock.
The thing that imparts the most energy to the gun in firing is the Frizzen.  A good lock with a lighter frizzen will not cause problems even with stiff springs.
Dan

[CHARLY]

I checked a new large Siler and on my new fish scale, and it required 15 or 16 pounds to pull the hammer back to full cock.
A new small Siler took 8 pounds to half cock and 11 pounds to full cock.
A 35 year old Durs Egg lock took 8 pounds to half cock and 10 pounds to full cock.
And an original fine condition Baker flint lock took 15 pounds to half cock, but only 11 to go from there to full cock.

The scale hook was on the top jaw screw for the test, and I kept the scale pull perpendicular to the axis of the hammer.

As for 'feel' the old Baker was by far the best. The Durs Egg was very smooth. The Silers, both so-so.

I also checked a couple of my original guns for 'feel', though didn't measure them with the scale. Both took more force to pull to half cock, than from half cock to full cock. Like the Baker lock did. I've heard this before from a number of guys and I'm supposing this has to do with better geometry/spring quality in the old locks, than with the new ones.

John

 THANKU SO MUCH JOHN ---
 that's all I really wanted to know --
obviously --my mainspring is far too powerful --

the scale was hooked on to the  top of the screw that holds the flint JAW down
in other words ---directly onto the place where anyone would INSTINCTIVELY grab & pull the darn hammer back ---I am no fool as others seem to believe--AND  it was parallel to axis of hammer--

27 lbs was rather too much as I suspected --THAT  is why I asked a logical question--
as I have never seen any scientific data on this mainspring tension

--so I will simply forge another --
 appreciate your help tremendously - John---problem solved  -thanku so much
C

[E.vonAschwege]

 that's all I really wanted to know --
obviously --my mainspring is far too powerful --

-I am no fool as others seem to believe-  

--so I will simply forge another --
C

Charly,
  I don't believe anyone here thought you were a fool - more so I don't think anyone here had ever thought to measure the draw weight of the cock on their guns.  So much about these locks is primitive technology and is done by "feel".  A series of springs made for the same lock all might work, one might just work a bit better than the others.  If you mentioned initially that you were forging the spring out from scratch, there wouldn't have been as much head-scratching on our end.

 Instead of forging out a new spring, Can you grind some of the thickness from your current spring to weaken it?  Test it gradually as you go until you're satisfied with its weight.  
-Eric

[jerrywh]

 No body is a fool for asking questions. The fools are the ones who don't ask or think they know everything.
 As far as your question goes it is not possible to answer because there is no way to average all the locks around.
 However, I personally am a believer in very strong main springs. I suspect you are asking this question because you are having some problem that you think this may be causing. If so tell us what that is. A strong spring is not usually the reason that flints break if that is the problem.   

[CHARLY]

 
 ok -- thankyou -- Jerry --Eric
appreciate your sage advice ---
novice lock builder --wish I had several locks to test /mess with
to get the "feel"
will try to grind spring thinner ---
 the lock  I made was painstakingly copied from a PDF  French 1770 lock- sent from  Poland
 has very detailed  dimensions ----exactly what I needed --waited 6  months for
 the mainspring max thickness is shown 3.8 mm at V bend --tapers to 2 .4 mm at cup hook end ---first time I have ever seen such accurate /specific dimensions --no more estimating from fotos---

shattered /blunt flints after only a few shots --tells me  this spring
acts like a recurve force draw curve ---starts easy 8 lbs --gradually stacks up --till last 1/2 inch --where it suddenly requires 27 lb to click into sear/trigger engage position

so  JTR  is spot on ---his 15 lbs max ---should be ok-- as he went to all the trouble to test with fishing scales on various locks --
so will try to grind thinner --- or remake a slimmer mainspring with the correct stock  Mark SENT  me ---
 back to forge ---learning fast --thanks to all your help
 appreciate
 C

[CHARLY]

---- Apologies ---nearly forgot
thankyou  Ky -  Flinter -and  Chris for your help /research
and any others I may have missed

appreciate all your help tremendously--will let you know how the new mainspring performs

shattered nearly all of  Mark,s superb English black flints he so kindly sent me

so ---ifthe problem is not this  French mainspring monster ---I will soon find another problem

--but that's for all you experts to have fun solving--
I just keep learning from dumb mistakes --- Mark said it takes years to get right !
   - one more question --

what is the safe clearance for lead ball -inside a 62 cal barrel sides--?--5 or 10 thou ?
ie what is  average OD  for a lead cast ball ---for a 15 .5 mm inside diam barrel?

ie what clearance is considered "safe " ?

or is a tight fit ball rammed down into breach dangerous --?
again --what pressure is required to force a patch and llead ball  -with ramrod--down a barrel into breach ---ie std muzzleloading procedure /?

OR IS IT  a case of "feel " again ---
apologies for these questions -----but some of us have never been shown actual muzzle loading effort /strain to push lead ball down ---say a 50 cal barrel --

appreciate any feedback or data ---to prevent me blowing my jaw off
( can black powder 3f  or similar--ignite by tamping too hard --the lead shot /wad into the powder?)
all these seemingly instinctive NORMAL actions one sees ---in movies --
 is a lot more difficult to execute in reality--!--- my lead " slug " slides easily down barrel
---with aprox 10 thou clearance  on circumference---with gravity--the lubed patch cloth
makes a loose snug fit --no rattle or ball wobble is apparent--very little ramrod push is needed--to seat the ball ---should it be rammed TIGHTLY?
 I have no idea of the correct loading procedure -- just ad lib as I go --and that's not wise!

regards -- C

[Bill Paton]

Charley, I have two thoughts about your lock problems.

1)  The sudden jump to 27 lb force to cock the piece sounds decidedly abnormal. I have seen that sudden high magnitude jump occur when the paw of the mainspring (sliding on the spur of the tumbler) is too long. The overly long mainspring paw can contact the body of the tumbler toward the end of the cocking motion and the tumbler can actually begin to compress the mainspring LENGTHWISE, causing a great and sudden increase in cocking force. The solution is to shorten the mainspring.

2)  The cocking force should be measured with a scale always positioned along the arc perpendicular to the long axis of the cock. This keeps the effective lever arm of the cock constant, and duplicates the arc our thumbs follow when we cock the piece. You will notice when cocking a flintlock, the thumb does not pull straight back parallel with the barrel. It naturally applies its cocking force in an arc that stays perpendicular to the long axis of the cock. Our brain-thumb connection automatically understands the best leverage position for cocking the lock, and the scale measurement should duplicate that.

Please let us know if either of these issues applies to your lock or measurements.

Bill Paton

[jerrywh]

  I like strong springs but not that strong. Sounds ridiculous to me.

[JTR]

Charley, I have two thoughts about your lock problems.

1)  The sudden jump to 27 lb force to cock the piece sounds decidedly abnormal. I have seen that sudden high magnitude jump occur when the paw of the mainspring (sliding on the spur of the tumbler) is too long. The overly long mainspring paw can contact the body of the tumbler toward the end of the cocking motion and the tumbler can actually begin to compress the mainspring LENGTHWISE, causing a great and sudden increase in cocking force. The solution is to shorten the mainspring.

Bill Paton

Charley, Pay particular attention to Bills' comment regarding the spring being too long. That could easily cause your problem.

Also, check that you have enough arch at the toe of the spring, where it rests on the tip of the tumbler spur. Watch the tip of the tumbler spur as you cock the lock to be sure that the tip of the spring stays in contact with the tumbler spur as it travels, and that the tip of the spur does not start pressing against the spring as the hammer comes back to full cock.
John 

[Bob Roller]

Charley, I have two thoughts about your lock problems.

1)  The sudden jump to 27 lb force to cock the piece sounds decidedly abnormal. I have seen that sudden high magnitude jump occur when the paw of the mainspring (sliding on the spur of the tumbler) is too long. The overly long mainspring paw can contact the body of the tumbler toward the end of the cocking motion and the tumbler can actually begin to compress the mainspring LENGTHWISE, causing a great and sudden increase in cocking force. The solution is to shorten the mainspring.

Bill Paton

Charley, Pay particular attention to Bills' comment regarding the spring being too long. That could easily cause your problem.

Also, check that you have enough arch at the toe of the spring, where it rests on the tip of the tumbler spur. Watch the tip of the tumbler spur as you cock the lock to be sure that the tip of the spring stays in contact with the tumbler spur as it travels, and that the tip of the spur does not start pressing against the spring as the hammer comes back to full cock.
John  

I would think that very much lineal compression of the lower limb of a mainspring would possibly snap off the pin on the upper limb.

Bob Roller

[CHARLY]

 NO --   BOB ---

 THE  clearance at full cock is fine --5 -7 mm --no lateral compression of mainspring
--after 200 shots it shud have broken or something snapped --but its still 27 lbs
--its stacking up gradually -- at half cock position ( I have omitted the notch in tumbler)
its already compressing this afRENCH  1760 large spring --
 nb this lock is much bigger than a  Siler ----so is my modified tumbler "spur " --much longer--22 mm radius---as my axle cock hammer is a huge 12 mm  HT  bolt --
also modified --to a woodruff key slot milled in --by hand
 - my tumbler spur /horn -describes a wider arc /travel than the tiny fiddly little 12 mm siler tumbler --at 22 mm ---

 you are right however about the  PAW  or cup hook ---way too shallow
 but --as I cannot show you my fotos and close -ups
 you will soon see the problem --
27 mainsprings later ---ther is  NO  collision at the final  cocking point --
the big beefy spring id dead accurate from the  PDF  I was given 6 months ago

I compared /measured this m spring with all the actual sized fotos on track of wolf --
its a cm longer --& thicker

luckily  Bill  Paton has emailed me --direct --SENT  him the pics
 have attached the fotos of my crude amateur lock --loaded and relaxed
 you can see the modifications that will probably attract scorn from lock purists--
but hundreds of shots later its still ok -just grunt when loading--a bit

but its all bush made --no luxuries here --and I enjoy the hard learned experience
no better way than making mistakes --if I am not in plaster!

many thanks to all your valuable help
one day I will have a genuine lock to get the feel /dimensions off --

but for now its scrapyard dynamics ---poor man,s lock build --every single bit --
 ok see ya --  C

[Acer Saccharum]

Charly, I congratulate you on your bush made lock. This is a challenge few of us here in the land of plenty would be willing or able to tackle.

[CHARLY]

   Has anyone  tried to calibrate the load /effort  required to load a std lock hammer?

what is the acceptable  poundage or ft /lbs ---or tension on mainspring of a average long rifle
lock ---that is required ---to load the hammer?

I used a rather primitive fishing scale--recorded a shaky 27 -30 lbs average

is that too much ?----if so ---what is correct tension ?

appreciate any data ---

As others have mentioned.
On many of the locks made in England (at least) and especially the late locks like Mantons etc with a linked mainspring the initial pull is much harder than it is nearing full cock due to the "arm" of the lever being shortened as the tumbler rotates if the link-tumbler-mainspring are in the proper relation to each other. At full cock this reduced pressure reduced wear on the sear and the tumbler also made it easier to get a nice trigger release. Most locks  found on Kentucky rifles were not so well engineered.
The pressure is really not that important on a flintlock. If it functions well and the cock fall is not too slow then the mainspring strength is probably proper.
I never bothered to measure it but I am sure my Manton design lock requires a pretty hefty pull to come to 1/2 cock.
The thing that imparts the most energy to the gun in firing is the Frizzen.  A good lock with a lighter frizzen will not cause problems even with stiff springs.
Dan

 Hi Dpahriss--

 you have me curious
you mention a "linked mainspring-"--- on a MANTON  lock

can you --if possible --post a foto of this "linked mainspring "
I would really be grateful --it sounds intriguing
 
by the way ---you guys were all more or less correct
 the spring paw --as  William  Paton - showed me--
---is the culprit ---I made the inverted cup too shallow
--did not snag on tumbler ---but the tumbler horn
 moved closer /crept onto the thicker "wrist" of the paw -
ie it hit a bump just b4 engaging the sear at full cock--
--hence the dramatic jump in final pull poundage --

problem solved --my lousy amateur paw will now be re-forged
--or another agonising mainspring made with a big deep cup /paw hollw

or I may try to build that fascinating STIRRUP --- I SEE ON PERCUSSION  locks
---that pivot action may reduce resistance----

anyhow ---love to see a linked mainspring on  Manton lock
 Thankyou for the supa info
 regards --
  Charly--