The Savage Breech Plug.

[ET1]

This is one of the most unique in design and quite often carried over into smokeless muzzle loader builds. The most popular build is the .45 with the .416, .40 and .375 coming from the rear. In most of these builds the Savage BP is the first choice for their build.
So why is this BP so popular? Understanding how it operates might reveal some of the reasons why.

10ML-II Breech Plug.JPG


We basically install a 209 primer at one end and at the other end a vent liner with a particular size orifice. In between we have a gap that is often referred to as the Flame Channel that serves a dual purpose.
Before I go any further the principle of operation I’m about to share has been accepted as such by many others and not simply concocted by me.

When the primer is detonated it dumps a good amount of thermal energy into the flame channel which in turn is bled off in a regulated fashion by the vent orifice into the bore to ignite the powder. As powder in the bore ignites it begins to build pressure to a point that any further feed of thermal energy is stopped from the flame channel and now bore pressure again regulated by the vent orifice will start to flow back through into the flame channel. The flame channel now becomes a cushioning reservoir so to speak to reduce max pressure the spent primer will be exposed to.

What some deem as the weakest link in this design is the vent liner because of the wear of the orifice hole. To extent the vent liner usage you can use a stronger grade material but you have to make your own. The material normally used for purchased vent liners is Grade 8 material. You can purchase Grade 12 material screws but IMO you need cobalt drills to get a decent number of vents drilled per drill.

Another approach being developed for a vent liner replacement is using bushings of hard material such as tungsten alloy or even pure tungsten. The required orifice hole is being accomplished with an EDM process. Then the Breech Plug is modified for the bushing and secured with a retaining fastener that is screwed over the bushing. Sorry I don’t have a picture of this off hand to share.

Some of you are probably aware of ignition systems that employ Large Rifle Primers and modules. For my purpose the 209 is simple and functional so at the moment I have no interest in possibly changing it. Just a mention that I do know it exists.

Just a final note.
The volumetric space of the flame channel does play an important role and if you want to have a little fun you can actually calculate the volumetric space by using this formula.
Pi x radius squared times x length.


Ed

[bellerivercrossbowhunter]

Thanks for the info.

I have a brand new savage 10ML ii on the way so I hope you don't mind me picking your brain to ensure mine performing @ it's optimal level...

[ET1]

Thanks for the info.

I have a brand new savage 10ML ii on the way so I hope you don't mind me picking your brain to ensure mine performing @ it's optimal level...

Whatever knowledge I posses is yours or anyone’s for the asking. I can’t guarantee I will have all the answers. I went down a long road about learning of the 10ML-II and hope to share to make someone’s else’s journey less tedious and as long as mine was. I seek no recognition like some might think but a willingness to share and learn from others even in different sections of the board.

This thread is not finished with more to come. I didn’t want to start an information overload that could cause more confusion and harm for learning.

I left off with the mention of the flame channel and will continue from there with this.


Breech Plug Fouling.jpg


Ed

[ET1]

Where I sort of left off was actually in my second post just with a picture of a clean and fouled breech plug. This was intended to show you how fast these plugs can foul. This in turn alters & reduces the volumetric space available for thermal energy and handling return pressure from the bore. I’ve never allowed my shot string to go over say 24-shouts with 6 additional primers for between intermittent bore cleaning. So I can’t say what happens should the BP fouling be allowed to increase even more.

When I first started cleaning my BP I just used a .156” drill and kept the center cleaned out not paying close attention to the carbon buildup on the shelf where the primer enters the BP.
Then one range outing I had trouble seating the primer and difficulty closing the bolt forcing me to apply some effort to close the bolt. On my last shot pushing harder on the bolt wasn’t enough so I just gave her a little snapper push forward. What a stupid move on my part because the primer went off and ignited the load. The 10ML-II was facing down range sitting on the rest with the rear stock supported with my left hand. The recoil caught my left hip inches from my family jewels. Just glad only my pride was hurt.

Valuable lesson learned, 209 primers don’t need to be stricken on the head to ignite them period. Most would not share such an incident because of their pride but if mention of what can occur helps prevent someone else from making this same mistake then I’ll gladly eat my pride.
After that the area where carbon can build up underneath the primer definitely gets cleaned.

There is no specific method to clean your BP so I’ll just share mine. The picture below is of a kit I put together. The vent comes out and the two different sized drills with a modified drill chuck go to work first. Then an older 10/32 tap is run into the threads to remove any carbon deposits left behind. If the vent orifice size is okay I recoat the thread on the vent with nickel based anti-seize grease before installing. This nickel based grease is also used on the threads of the BP. Then I’m done with the BP.

Breech Plug Cleaning Kit.jpg

One thing I forgot to mention is if carbon removal is required on that first diameter going into the BP I just lightly scrape that area.



Ed

[MikePal]

There is no specific method to clean your BP so I’ll just share mine. The picture below is of a kit I put together. The vent comes out and the two different sized drills with a modified drill chuck go to work first. Then an older 10/32 tap is run into the threads to remove any carbon deposits left behind. If the vent orifice size is okay I recoat the thread on the vent with nickel based anti-seize grease before installing. This nickel based grease is also used on the threads of the BP. Then I’m done with the BP.

Breech Plug Cleaning Kit.jpg

Holy crap Ed....sounds like a lot of work....all I use to clean my breach plug after using Triple 7 is a cup of hot;



(just poking fun Ed ..giggles)

[impact]

This works the best for me. I pre soak the breech plug in Hoppe's no 9 and it comes out shiny and new.




Nothing effects the performance of your muzzleloader more than the breech plug. When you are using a high performance powder like Blackhorn 209, it is very important that your breech plug be as clean as possible. Normal use leads to primer fouling buildup in the flash channel. This fouling is extremely hard and can lead to poor accuracy, misfires, and hangfires. Primer residue cannot be adequately removed with a brush, pick or pipe cleaner so we recommend a thorough and regular cleaning of the breech plug before using Blackhorn 209. The use of a drill bit assures a perfectly cylindrical flash channel, which promotes a consistent ignition and better overall accuracy. Be sure you use the correct diameter drill bit for your breech plug and DO NOT remove any metal from the breech plug during the cleaning process.

The following cleaning procedures will ensure your muzzleloader performs at its best when using Blackhorn 209. Insert a drill bit suitably-sized to fit the flash channel and GENTLY TURN BY HAND to remove excess fouling/buildup. Use a torch tip cleaner of the appropriate size to clean the flash hole. Use solvent to remove any remaining residue (we recommend Blackhorn 209 Cleaning Solvent by Montana X-Treme). Dry with compressed air or ensure the flash channel and flash hole are completely dry before use. NOTE T/C, Traditions and most Knight breech plugs use a 1/8″ drill bit For CVA use a #32 drill bit. Numbered drill bits are machinist bits and can be found at various online supply houses like ENCO, or search “numbered drill bits” for more

[ET1]

MikePal

Here I thought you were being a gentleman offering me a drink.
Just in case my choice is chilled Diet Pepsi straight up, chuckle.


Impact

Thanks for sharing your method that offers the shooter another choice or option to try.



Ed

[DJB]

Check out the Eezy-Breech at www.plugcleaner.com. I found this to be the easiest way of cleaning the primer pocket, flash channel and flash hole in seconds. I don't even have to remove the plug. The tool is relatively inexpensive.

[MikePal]

The tool is relatively inexpensive.

The web site says it's $16 US (approx $20 CDN) ..a tad on the expensive side for two drill bits

http://www.plugcleaner.com/shoppingcart.htm