Nipple to bolt head spacing

[Harald]

Being a newbie to black powder, I'm not sure it what I'm experiencing is normal or desireable.  While inspecting my new Knight Disc Extreme rifle, I noticed that there's a gap between the bolt face and the cap when it's installed on the nipple.  In the metallic cartridge world this would be undesireable because you want the bolt face to hold the cartridge in the chamber, but I realize I'm in a different world with the muzzle-loader.

It would be easy to measure said gap and install an appropriate shim under the nipple to eliminate the gap.  But is this needed or a good idea?  I'm asking because the CCI musket caps I'm using are peeled open and there's a lot of combustion debris in the bolt area after firing the gun.  Is that normal?  Please enlighten this newbie.

[jackelope]

Normal.

[Magnum_Willys]

Consider a standard side hammer muzzy - the hammer to cap gap is inches.  Now if your firing pin is weak or short then it could be a problem - like many northwest traditions striker muzzys.

[theleo]

With a muzzle laoder you've already loaded the cartridge into the chamber before you've put the nipple on (powder and projectile). The primer is being used only as an ignition source for the powder, the projectile (ball, bullet, sabot...) and powder are being supported by the barrel by the very nature of them being used a muzzle loader.

[goldenhtr]

"I noticed that there's a gap between the bolt face and the cap when it's installed on the nipple."

It's there to make the gun Washington State Legal.

[Sabotloader]

Being a newbie to black powder, I'm not sure it what I'm experiencing is normal or desireable.  While inspecting my new Knight Disc Extreme rifle, I noticed that there's a gap between the bolt face and the cap when it's installed on the nipple.  In the metallic cartridge world this would be undesireable because you want the bolt face to hold the cartridge in the chamber, but I realize I'm in a different world with the muzzle-loader.

It would be easy to measure said gap and install an appropriate shim under the nipple to eliminate the gap.  But is this needed or a good idea?  I'm asking because the CCI musket caps I'm using are peeled open and there's a lot of combustion debris in the bolt area after firing the gun.  Is that normal?  Please enlighten this newbie.

In the very early models, it was Knights intention that the hammer when in the fired position should NOT hit the top of the nipple.  The hammer dropping on the nipple could and would eventually cause the nipple to peen and it would not ignite the cap.  It was a good thought but I am not so sure that in real life it was the best ideal.  Because of the different tolerances of all the parts involved this thought has caused them some problems because there have been Western Knights out there that are not igniting the cap - putting a dent in them but not igniting.  Mine I have modified to make the sure that problem does not occur - and yes because of that - I do not ever allow the hammer to come down on the nipple without a cap.  And when I do peen (round it) the nipple they are $4 bucks for a new one.  Not much to insure that the rifle goes off every time - especially hunting.

If yours is shooting with out any hitches it is good to go.

[Harald]

Thanks all for reassuring me that this is normal.

@theleo
I understand that there's not the same situation of a modern metallic cartridge backing out and blowing the rim off.  I was just wondering whether having a larger gap allows the musket cap to back up more and blow more combustion gas into the bolt area.  I'm guessing there's no practical way to seal the cap off so that no gasses blow back and still have an easy to reload system.

@Goldenhtr
I thought what makes it WA legal is that part of the bolt collar is partly cut away so that the cap is exposed to the elements?  If that cutout were not there, then the whole area would be closed off from weather.  I've never seen a Knight Disc Extreme without the Western mod, so can't say for sure how it differs.

@sabotloader
Obviously no hammer on my gun, but I did notice that the nipple is offset from the threaded portion that screws into the breech plug.  The affect of this is that the firing pin will impact an edge of the nipple and not go straight into the center of the hole.  Makes sense to have such a hard backing to ensure that the cap goes off.  Sort of reminds me of a rimfire cartridge firing system (and the potential damage when dry firing).

Now that I'm thinking further about how this works, I plan on measuring how far the firing pin sticks out when fired and comparing it to the bolt face to nipple dimension to make sure the firing pin won't stop short of a deep hit into the cap.  I know you can adjust firing pin extension depending on how far you screw the assembly into the bolt body.

[Sabotloader]

Thanks all for reassuring me that this is normal.

@theleo
I understand that there's not the same situation of a modern metallic cartridge backing out and blowing the rim off.  I was just wondering whether having a larger gap allows the musket cap to back up more and blow more combustion gas into the bolt area.  I'm guessing there's no practical way to seal the cap off so that no gasses blow back and still have an easy to reload system.

@Goldenhtr
I thought what makes it WA legal is that part of the bolt collar is partly cut away so that the cap is exposed to the elements?  If that cutout were not there, then the whole area would be closed off from weather.  I've never seen a Knight Disc Extreme without the Western mod, so can't say for sure how it differs.

@sabotloader
Obviously no hammer on my gun, but I did notice that the nipple is offset from the threaded portion that screws into the breech plug.  The affect of this is that the firing pin will impact an edge of the nipple and not go straight into the center of the hole.  Makes sense to have such a hard backing to ensure that the cap goes off.  Sort of reminds me of a rimfire cartridge firing system (and the potential damage when dry firing).

Now that I'm thinking further about how this works, I plan on measuring how far the firing pin sticks out when fired and comparing it to the bolt face to nipple dimension to make sure the firing pin won't stop short of a deep hit into the cap.  I know you can adjust firing pin extension depending on how far you screw the assembly into the bolt body.

Well in away you are correct - but when you order that assembly is it called a 'hammer assembly' even though most would call it a firing pin.

The offset is with a Musket cap nipple - the surface of the hammer is not large enough to cover the entire musket cap and drive the edges of the cap into the nipple.  To compensate for this Knight off-sets the musket nipple so a portion of one edge of the cap is always under the portion where the hammer hits - there fore giving you ignition.

Were I you I would seriously consider using the #11 nipple and shooting RWS Dynamint Noble 1075+ caps.  They are as hot if not hotter than a Musket and with the #11 cap placed on the nipple in the middle of the BP the hammer pressure on the cap can drive most of the heat and pressure the cap generates directly down through the nipple flash hole to the powder.

Can to a certain extent - but if you install the hammer assembly in correctly you get the correct length - if you install it to tight the bolt will not operate correctly and if you install at less than the correct spot it will shorten the hammers extension out of the bolt face.

Have you already take your hammer assembly out of the bolt?  If you have there is really only one spot that is the optimal spot to release the secondary hammer.

When you take yours apart again - screw the secondary safety in as far as it will go - make sure it is at the end of it throw.  Turn the hammer assembly in clockwise as far as it will go.  It should go some distance beyond alignment.  In most case ff the distance is less than a 1/2 turn you will need to turn the hammer assembly CCW back to alignment and one additional full CCW turn to alignment then release the secondary safety. This should give you the optimal throw of the hammer when you release it to the nipple.  When you do release it - the bolt handle UP - pull the trigger and slowly push the bolt handle down that will release the hammer to move forward without dry firing and possibly reaching to top of your nipple.

This is the position that Knight would like to see with cap installed and bolt closed



This picture should show you the approximate distance the hammer protrudes from the bolt face when it is in the correct position...



Hope some of this helps a bit...

[Harald]

Thanks Sabotloader.

I will definitely try the #11 caps you recommended.  I've been having trouble with my Cash musket capper because it crushes half the caps in the holder when dispensing them.  I'm thinking a #11 capper wouldn't have this problem.  My main reason for starting out with the musket caps is because I saw a chart that shows the magnum #11 and musket cap put out the same temp flame, but the musket cap produces a much higher volume of gas.  I don't get many opportunities on legal deer here in WA and want to make sure that the gun will go boom when I touch it off.

Thanks for the assembly pics.  I printed the page and will check it out on the gun.

[Sabotloader]

Thanks Sabotloader.

I will definitely try the #11 caps you recommended.  I've been having trouble with my Cash musket capper because it crushes half the caps in the holder when dispensing them.  I'm thinking a #11 capper wouldn't have this problem.

If you can find a Traditions Brass Capper - it really works well with #11 caps...




 

My main reason for starting out with the musket caps is because I saw a chart that shows the magnum #11 and musket cap put out the same temp flame, but the musket cap produces a much higher volume of gas.  I don't get many opportunities on legal deer here in WA and want to make sure that the gun will go boom when I touch it off.

You are correct that the Musket cap has more volume - but IF you powder is dry it really doesn't matter... but if your powder is damp the extra volume could be an aid in that you would probably get a delayed fire but the gun could still go off.

Thanks for the assembly pics.  I printed the page and will check it out on the gun.

later - mike