Original Knight Disc Extreme with Power Technology

[Mark Strong]

New to muzzleloading. What Breech plug can be used to replace the existing long stem power technology plug in my original Disc Extreme 52 Cal. I prefer to use 209 powder for all my rifles and 209 gives me a hang fire. I believe that is does not have enough volume to get past the long stem. If no breech plug is available what is the bet powder to use with this long stem.

 

[GM54-120]

Lehigh bare primer plug and NFPJ adapter is the easiest and cheapest route. Get a 4 pack of vent liners at the same time.

Lehigh bare primer plug with 1 vent liner. $16.50
https://sskfirearms.lehighdefense.c...reme-master-hunter-and-long-range-hunter.html
Adapter for the bolt. It stays in unless you remove the bolt. Not something you need to remove each shot. $14.50
https://sskfirearms.lehighdefense.com/bare-primer-adapter-knight-disc-elite-extreme.html
4 pack of vent liners $22.00
https://sskfirearms.lehighdefense.com/vent-liner.html

 

[GM54-120]

IIRC the Power Stem plug was intended to be used with 130gr of Triple7 by volume or more. So since its by volume you could use any sub besides BH209 with it. Real black should also work fine as long as you are between 130gr and 150gr by volume.

 

[Mark Strong]

Thank you for the reply. When I purchased the gun from a friend he gave me a couple canisters of Jim Shockeys Gold FFG. How is that powder replacment in this situation with a 325 grain bullet? Does the 130gr to 150gr still apply. Again only been shooting a muzzleloader for a year and learning each day.

 

[GM54-120]

The 52cal was rated for upto a 375gr bullet and 150gr of loose Triple7. Shockeys is a rebranded American Pioneer Powder product. Its less powerful than Triple7 and more "chunky". My only concern would be how well it settles between the stem and bore.

About the only good thing i can say about it is......Its easy to ignite and cleans up easy. Less corrosive than Pyrodex and much less crud ring than Triple7.

 

[longbowsteve]

We always just used regular disc extreme breech plugs in the 52 cal at the factory.Works better than the power stem.

 

[GM54-120]

The factory FPJ plugs ignite any powder but BH209 just fine every time. They work with BH209 too but not as well as a bare primer setup. Knight wants over $25 for 1 breech plug and about $15 shipping. That is more than half the way to the price of a full kit at Sportmans Warehouse but they are out of the Extreme bare primer kits. Not sure if they got just plugs.

It would not surprise me if one of the guys here has a FPJ plug they could spare. Most of us swapped to bare primer and wont go back to FPJ.

 

[GBG]

The 52cal was rated for upto a 375gr bullet and 150gr of loose Triple7.

FWIW, I contacted Knight by email in 2018, asking what the upper limit on bullet weight is with maximum allowed powder charges. The email reply stated there was no limit on bullet weight.

I've shot 600+ grain bullets over 150 grains Pyrodex RS in the Disc Extreme several times, with no malfunctions or noticeable blow back from bare primer breech plugs. I'm still reluctant to try that much Triple 7 under 600+ grains of lead. The 150 RS load has penetrated two feet of soft poplar firewood (using heat treated WW bullets), and recoil already exceeds my senior citizen comfort level.

If this information is in error please correct my misunderstanding.

 

[Mark Strong]

We always just used regular disc extreme breech plugs in the 52 cal at the factory.Works better than the power stem.

Did they use the bare primer plug or the breech primer that uses the orange disc?

 

[longbowsteve]

Almost all of us at the factory used the standard Disc Extreme plug with the red full plastic disc and FFG triple 7 powder. I personally used 100 grains with awesome results. The power stem BP was a gimmick,in my opinion.I also prefer the 375 grain Barnes bullet,for what that is worth.

 

[GM54-120]

The Powerstem did increase velocity but it also creates other issues such as you cant swab all the way down and ive seen people post about barrel damage. Not with the 52cal but when the stem was used in a 45cal with big loads of powder.

I actually have a Lehigh stemmed vent liner prototype. You can remove the stem and its much shorter than the OEM Knight stem. While it worked fine with Triple7 it would not work reliably with BH209.

Im not sure if you have seen a "vented set screw" before. Its sort of like the lock collar used to hold the bushing in a carbide plug. I always wanted to try one that was an inch long over the carbide bushing. The hole or vent in that screw is about .060. Its the only easy way i can think of to make a bare primer "stemmed" plug that might light up any powder.

 

[Mark Strong]

Lehigh bare primer plug and NFPJ adapter is the easiest and cheapest route. Get a 4 pack of vent liners at the same time.

Lehigh bare primer plug with 1 vent liner. $16.50
https://sskfirearms.lehighdefense.c...reme-master-hunter-and-long-range-hunter.html
Adapter for the bolt. It stays in unless you remove the bolt. Not something you need to remove each shot. $14.50
https://sskfirearms.lehighdefense.com/bare-primer-adapter-knight-disc-elite-extreme.html
4 pack of vent liners $22.00
https://sskfirearms.lehighdefense.com/vent-liner.html

Sorry for so little knowledge on this but I do have one question that I could not get answered on You-Tube. How does the adapter fit or attach to the bolt? Bare primer plug is back in stock.

 

[michiganmuzzy]

Sorry for so little knowledge on this but I do have one question that I could not get answered on You-Tube. How does the adapter fit or attach to the bolt? Bare primer plug is back in stock.

When you remove the bolt from the rifle the adapter just drops right into the nose where the FPJs normally go. Except that when the bolt is reinstalled the adapter can not fall out or be removed without removing the bolt again. But the bare primers just drop into and out of the adapter.

 

[HC]

just remove the bolt from rifle, insert bare primer adapter into bolt, replace the bolt into rifle. Hope this helps.

 

[michiganmuzzy]

Best thing youll ever do to your DISC gun

 

[GM54-120]

It just slides in just like a red plastic jacket but ONLY with the bolt out. After that its stays in the bolt and you just drop a bare 209 in the adapter. The adapter will not come out until you remove the bolt again.

 

[Mark Strong]

View attachment 17399 just remove the bolt from rifle, insert bare primer adapter into bolt, replace the bolt into rifle. Hope this helps.

Perfect, pictures work miracles for the challenged. Thank you.

 

[Mark Strong]

Lehigh bare primer plug and NFPJ adapter is the easiest and cheapest route. Get a 4 pack of vent liners at the same time.

Lehigh bare primer plug with 1 vent liner. $16.50
https://sskfirearms.lehighdefense.c...reme-master-hunter-and-long-range-hunter.html
Adapter for the bolt. It stays in unless you remove the bolt. Not something you need to remove each shot. $14.50
https://sskfirearms.lehighdefense.com/bare-primer-adapter-knight-disc-elite-extreme.html
4 pack of vent liners $22.00
https://sskfirearms.lehighdefense.com/vent-liner.html

Thanks again for your help. Finally getting around to ordering the Lehigh bare primer plug for the 52 Cal. Hadthree weeks of hunting to get in. Did get an elk with the 50 Cal so it was a success. I can't see in the string regarding powder for this conversion. Will I need to use 777 or can I use Blackhorn?

 

[GM54-120]

The bare primer plugs were designed for use with loose powder. Either is fine just not intended for pellets. BH209 reliability was the main goal but as long as its loose powder im sure it will be fine.