In my Black Diamond XR I shoot only 209 primers even though I have the #11 and the musket nipples for it. It never gives me any problems.

It sounds like the cap is setting itself. I have one rifle that does the same thing. It is one of my Wolverines. And this is what I do... (do this at your own risk)

1. the rifle is empty and I am ready to load.
2. cap the #11 and then and fire it. 90% of the time the cap will not go off, but instead sets it self. It will fire the next time I **** and fire the rifle.
3. Load the rifle
4. pull back the hammer and take the shot.

Somethings I noticed about my Wolverine. When it starts to act up... it usually happens when the nipple is fouled real bad. So I take a Q-tip and keep that nipple clean. A little alcohol on that Q-tip and rub the fouling off. Then it will normally fire the cap the first time.

So looking at this I noticed I'm missing a couple parts anyway.
http://www.brownells.com/.aspx/pid=0...tail/MLS_50_54

I don't have part number 6 or part number 48. What is part number 48? Not sure what happened to these but like I said has always fired fine up until now.

#6 is a ****ing handle return spring.
#48 is a nipple protector (I think this is taken off prior to use)

That is built very much like my Black Diamond although I have no part #6 or #48 either.

I'm going to try to call Numrich in the morning and see if they have the two springs in stock in the morning and see if I can get overnight shipping. I realize I will pay a ton for this but if it's under $50 I will be fine with it as I need this thing fixed. I don't know what that other part is so I don't really know how to check on it.

So I don't need #6 or #48? So If I'm going to try and replace the spring should I just not worry about the #6 spring?

Is this an area where I should pay the crazy high fee for overnight shipping or is there a good chance a gunsmith will have stuff like this?

I'm going to have to make up my mind if I should order it before I get time to check with gun smiths so if this isn't a common part I'd rather just order it overnight.

Looking at that schematic, it sure looks like you could find a hardware store spring that would do the job, either as a replacement or as a "helper" for your old spring.

I'm going to see if some gun shops have it today or one that will work. Seems like it would be particular to this gun though. I with Numrich and they said I'd have to allow 2-3 days before it it shipped even if I chose overnight shipping.

I'm really really tempted to just go buy a new muzzle loader. However, I don't have time nor want to waste the bullets to go sight it in before BP season starts. That and the fact that when this one shoots it just flat out shoots amazingly. It's probably the ugliest gun I have but it shoots the best.

Just because my Black Diamond XR does not use the same parts, does not mean you don't need it. That one on the hammer striker I would guess is important. I would try a hardware store as well. Take the part in that needed to be fitted. Lots of them Hardware stores have drawers full of different size and power springs.

How do I know what power spring I'd need to get? Or would I need to try several?

So you mean your Black Diamond doesn't use those parts at all or you don't have them?

Do I need the nipple protector thing? I figured out what the other small handle return spring does. I don't need it it just doesn't automatically push the little handle forward again after I pull it back to **** it. It stays back unless I push it forward manually.

And a "spring is just a spring". Nothing special about a gun spring. Just find one that fits OK and has the power to work well.