New Knight bare primer breechplug - 11/03/16
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.
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.