Home Forums Hunting & Shooting Muzzleloaders New Knight bare primer breechplug

It's no secret that hot primers are recommended for BH209. It's also well documented that the Knight bare primer guns have had problems with CCI magnum primers sticking in the plug and or the bolt due to blowback and possible headspace issues. As a result, I've been using standard Winchester primers, which are what I was able to find locally. While getting ready for Saturday's VA ML opener, the W209s seem to give good ignition, but accuracy was spotty, with occasional fliers. When I got home from the range, I went online to look into possible solutions and found a number of posts about the issue and also about flash channel erosion problems. I decided to order a new plug to have one on hand. I also emailed Knight about the projected lifespan for a plug. Their response was that a plug should be good for 500-800 shots, depending on the powder type and charge.

When the new plug arrived, it was clearly different from the original. The flash channel just in front of the primer was much larger. The actual touchhole seems to be the same (I don't have pin gauges). On my next trip to the range, accuracy was still spotty, and one shot was clearly underpowered, indicating poor ignition. Thankfully, I had packed the CCI magnums along and gave them a try. Accuracy immediately improved and there were no problems at all with sticking or bulging primers. Obviously, Knight finally figured out what was wrong and corrected it. Also obviously, the standard primers, which had just barely been getting the job done with the old plug, don't have the fire needed to work with the new design. The last thing I did was fire one shot each with 3 bullet/sabot combos other than the Barnes T-EZs I sighted in with. All of them struck within an inch or so of the 1" center dot on my targets at my sight-in range of 100 yards except the Nosler 300gr Ballistic Tip which was a couple inches out, but still in the killing zone.

When I ordered the new breechplug, I also ordered a cap ignition which I intend to use with black powder for shooting full-caliber conicals. That breechplug is very simple in design with the nipple leading into a good sized ignition chamber similar to a Manton breech, but with the fire coming into the rear. The kit came with both #11 and musket cap nipples.


Edit: What I left out was that during the first range session, accuracy was fine until I decided to try the CCI magnums again. After sticking a few primers, I went back to the W209s, but apparently the plug became fouled by blowback to the point the W209s no longer provided enough fire.

Knight bare primer breach plugs had a 5/32 flash channel since Lehigh started making them. If your old plug was smaller it was either a pre Lehigh plug OR you just have not cleaned it out with a 5/32 drill bit.

Ive used Win209s from the first day Lehigh started making Knight breach plugs and i never had a missfire or hangfire....not once.

Want a better plug that wont leak and primers wont stick? Contact bestill on the modern muzzleloader forum. His are made to order for your gun and they use a tungsten carbide bushing for the flash hole.

You will literally get 1000s of shots from the bushing before its needs replacement. Plugs are $80 or about $125 if he does the install.

THE answer. I can attest to that being truth.

Yep, ive got one and its perfect. Lehigh makes them for Bestill but he uses the original 17-4 stainless that Knight is too cheap to pay for. Current Knight plugs are 416 SS.

Each plug is fit to your rifle based on your measurements. Its pretty easy to do but if you are not comfortable just send it to him. He does top notch work.

Your primer sticking and even poor ignition is mostly poor headspacing. You can shim your existing plug as a band-aide solution. Add shims till you get a .003 crush on a primer and test it. Upto a .005 crush might be needed.

No need at this point. The new plug works fine with the CCI mags and I've got hundreds of those. I'm actually lookng forward to trying some FFG with conicals in this thing using the cap ignition. All the substitutes I used (Pryrodex, 777, and BH) have quirks. Goex just goes bang.

So, are you cleaning your Knight bare primer plugs with a 5/32 drill bit? The old bare primer plugs are 1/8".

No need?...shims are a few cents each and work until the flash hole wears out. Primers will almost never stick if the head space is set correctly.

Not sure why you feel the need for a cap when shooting conicals. A 209 works fine. Ive shot tons of them with a 209 primer and real black powder. I do prefer a cap for loose Triple7. The crud ring goes way down.

I clean them with the proper size drill, whatever that happens to be. I check for proper fit with the smooth end.

Why would I complicate my breeching with shims, when the new plug I have works perfectly well as is? I fired at least 20 rounds the other day without any sticking, bulging, or ignition trouble.

The breech plug for caps is, as I said before, a simple affair that I can just pick and prime like any other caplock. It's also easier to prime using a capper than the gyrations you have to fittting a 209 in the boltface. and, as you said, a cap works well with 777. When I was shooting 777 in a sidelock, I simply ran a dry brush down the bore periodically to keep the crud under control and kept on shooting. I like the way 777 performs, just not the problems with shelf-life, limited availability, and price.

Try something.

Measure the length of whatever primer you like to use.

Put it in the the action and close the action.

Remove the unfired primer.

Measure the primer again and post your measurements or the amount of primer crush you are getting. If you are not getting any crush, you still have a problem waiting to occur.

If both the new plug and old plug look like this on the powder end then they are both made by Lehigh and all Lehigh made plugs have a 5/32 flash channel



BTW Knight just started selling a 209 capper. It looks like it might work well. https://www.knightrifles.com/product/bare-209-primer-capper-decapper/

My primers (Win209s) come out squeaky clean on my stock UL plug, but just out of curiosity, how much crush should you be getting?

Also, I've heard the Knight plugs will wear out around 100 shots...I've shot mine over 200x. How do they wear out? Any signs I should be looking for?

My UL is an early one. The old plug has a 1/8" channel ; the new one 5/32.

Holston: Knight says a plug should last for 500-800 shots, depending on the powder and charge weight used. A set of pin gauges should allow you to measure the touchhole, but I don't have one as yet.

Squeaky clean is how a Win209 should come out. The plug was made for a Win209 to seal on the nose of the primer. A .003 crush works ok but closer to .005 is better.

The process of brazing in the vent liner greatly cut down on life of the plug. The vent liners are a real PITA to remove too. I know of several people that got less than 100 shots out of the brazed in vent plugs.

The original Lehigh plug vents lasted a much longer number of shots.

Bestill makes bushing plugs for the Ultra Light/Mountaineer. Lehigh only made removable vent plugs for the older DISC rifles before being contracted by Knight.

They still make all the plugs for Knight as far as i know.

Tagged one with the Ultra Lite yesterday. 290gr T-EZ over 80gr of 209. DRT at about 40 yards or so.

Wow, that is one freaky cool buck! Nice work!

Fwiw, I use W209's in my Knights also. Most have zero blowback without shimming (using actual Lehigh plugs).