Great adds Idaholewis & sabotloader! I'd like to know if this "fix" would apply to my Knight Bighorn. As you may remember, I have a 1x scope on it and I've had a heck of a time trying to insulate the scope from blowback. I used my T/C Renegade stock with the Green Mountain 50 cal barrel this season over my Knight partially because of this blowback issue. The T/C is just easier to deal with but I feel that I am still more accurate with the Knight. Nice finding you guys again.

No this solution is specific to bolt action Knights. There is no bolt handle on a Bighorn. Adding shims to a plunger gun wont do anything to help blowby.

As GM indicated the 'fix' will not help a bit with a Bighorn. I recognize and understand you problem with the scope. For myself when faced with this issue - I wrapped the scope in a 'bra'

This not a great picture but it shows the scope bra installed around the scope. Held in place with black zip ties



Another example



This a template that might help building a protection device

Thank you for the details Mike!

UBet! give it a try.

Nice fix on the Breech plug, but you'd think Knight would have addressed the problem and re made a better BP.

They certainly could probably fix the problem if everyone agreed to use the same primer! The primers come in many different dimensions, both in circumference and length.

SPOT ON!

When I owned the Knight Mountaineer in the Video above, I bought 4 or 500 Winchester 209s for use in it. I found that they Varied Slightly all throughout the Same Boxes, I ended up measuring and Sorting ALL of my Primers. I couldn’t use The Largest ones as they would Get “Sticky” to Extract.

As Sabotloader Said, If Knight were to try and Correct this, EVERYONE would need to Use the Same Brand of Primer, And even then you would likely end up needing to Sort Through them for Best Fit

Nature of the Beast, so to speak. If you take the Time to Follow the Above, It DEFINITELY Works. I got ZERO Blowback, I shot as many as 20-22 Shots on a Few Different Outings, and i use Swiss Real Blackpowder to Boot.

My Spent Primers from a Few outings



The Breech of my Rifle after Shooting, 100% CLEAN

As always you got me on that one, I should have known better myself that Primers are all different but I wasn't thinking. A Good Fix and Nice Video's on explaining the process.

It REALLY is a shame these primer Companies are not tighter on their Tolerances, But fact is they are not intended for what we are using them for, So we simply have to deal with it! The Best way is to Measure and Sort them. I found Variances in My Win 209 Primers ranging from .296 to .301, the .296-.299s were PERFECT in my Rifle, But i had to be Careful with the the .300-.301s, They created A Little to much “Crush” they would get “Sticky” to Extract. I almost packed up went home over this a Couple of Different Outings, I didn’t think i was gonna get the Primers out? This is when i decided to Measure and Sort all of my Primers. I had ZERO Problems after i Measured, and Sorted Primers.

With the Primer Variances, You can see how difficult it would be for Knight to Try and “Tighten” the Tolerance, It would end up being nightmare for them. It’s better for the Owner to Choose what primers he Wants to use? And Shim the Breech Plug accordingly. It would Sure be NICE if they Sent a Shim kit to Do the Job Though, instead of the New Owner of the Rifle having to Purchase them Separately :)