Blackhorn breech plugs.

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casper

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Does anyone make a custom breech plug to seal the breech of a Knight revolution that is Blackhorn compatible ? I love the rifle, hate the clean up.
 
Not that I know of. I don't think there are many here that have a Revolution. Didn't they only come with a breech plug for the Red Plastic jacket? I know this was asked before but don't think anyone had a fix for it.

The Knight KRB7 was a dirty rifle too that really did not reliably shoot BH. Me and one other member have modified those so they are clean and are reliable with BH but I don't think what we did would work with yours since the KRB7 only came with a naked primer breech plug. I would love to see one of those Revolution actions up close some time.
 
How do I get ahold of this Ron guy for breech plug mods ? :huh?:
 
No camera and not computer savy enough, sorry. Mfg # 900043 if that helps ? Midway has a good picture of it.
 
Here is what i think i might know now. The 900043 plug has a domed end. The 900024 has a small concave end, and is the same size as the 900043. It seems the 900024 should work in your rifle, and should ignite Blackhorn, but i really wouldn't know. There probably will be a lot of blowback.

What i would do to your 900043 plug is remove the dome, and create a chamber similar to the chamber of the 900024 plug; this would be done by utilizing a vent liner. Then it is possible the 900043 plug will ignite Blackhorn good, but there will still be a lot of Blow back. It may be, the Revolution is not meant to burn Blackhorn.. i know nothing of this.

If you wish, you can mail me your breech plug, and i will install a vent liner for you, but i don't know it this will allow you to use Blackhorn. It will cost you $25, and there is no guarantee.

Have you tried the 900024 plug?
 
I have not tried the 900024 plug, but I will look into it. Thanks. :D
 
When you shoot your Revolution now with a sub powder like 777 and the Red FPJ, do you get a LOT of soot (Blowback) into the action area?

If you do have a lot of blowback, I personally seriously doubt that you will be able to make that rifle shoot Blackhorn 209 until the leakage is stopped. There are 2 of us here that have the Knight KRB7. Those rifles did not shoot Blackhorn reliably, lots of fail to fires and no fires. My rifle had a stock breech plug the other rifle has one that had a ventliner installed in it. The one with the vent liner would not shoot BH209 reliably either. Just too much blow back. We made a couple other mods to make the action cleaner and when the leakage was stopped then all the pressure and flame got to the charge making them reliable, Mine still has the stock flash hole size too.

The primary difference I see between our KRB7 and yours is that the Revolution uses the Red FPJ. That is why I asked about blow back. If the Red FPJ sealed the action area up good then you stand a better chance than we did to start.

There was a post not long ago from someone that was asking if there were mods to just make the Revolution cleaner in the action IIRC.

Good luck with the project.
 
I just fired primers in it so far and it gets dirty all ready, even without powder. I'm going to give up on trying BH in that gun. :( Thanks everyone for your help. Where the action closes on the primer and plastic jacket it's spring loaded, so sealing the primer won't work, as when you fire the primer, the pressure pushes on the spring and pushes the primer back away from the breech plug, so it's not going to completely seal.
 
I'm the one with the other KRB7, one of the mods we did was to beef up the springs that hold our action shut. While the action is still able to move I find that it doesn't. I have since replaced y ventliner that I had bored out to .035 with a stock one and have had not ignition problems. I would be curious to know if a heavier spring would help. Don't people use the FPJ in the DISC line and ignite BH ok just a little dirty compared to the Lehigh Conversion? I also believe that Shawn's stock plug for the KRB7 is domed so I do not believe it necessary to remove it to ignite BH209.
 
Casper,

I have seen the Revolution only one or 2 times but did not really scrutinize the action, so I don't remember if it work like a Rolling Block (Like Our KRB7) or if it is more like a falling block. Doesn't the Trigger/Block assembly drop out of it? Is it possible you could take some close up pictures of it and post them?

If it works similar to the rolling block, then you might benefit from a similar mod to what we did. I just looked for a picture but can't seem to locate one at the moment. In ours we removed the spring from the Block Detent and installed a "Duplex" Spring (Spring inside of a spring). The larger spring was about he same size diameter of the original but was a bit stiffer, then inserted a stiff smaller diameter spring inside of that one. This allowed more force to be applied to the base of the block so it maintained more forward pressure on the primer under fire, yet was still not hard to pull back. We then made some mods to the primer pocket too but that was because the KRB uses a naked primer instead of the Red FPJ.

If it works like a falling block then I am not sure as I have not worked on one of those yet. Though I am hearing some rumors that my Uncle wants me to look at a falling block 22 for him when I head home next weekend that don't close up tight. Guess I also need to Prep my maintenance box with some spring stock. :think:

So if you can remove the Trigger group and take some nice pictures so we can see how it is made, who knows. Some of us like puzzles. :wink:

You are not the first to ask about that action, it is just not many here has or had one to work on and the couple that did I have not seen post in quite a while.
 
Shawn T, I don't have a camera or for that matter computer savy to post pictures, but if you GOOGLE knight Revolution recall there are a lot of good pictures there. I think if I tap out the 2 top roll pins that plunger assembly will come out and I can look for a stiffer spring set up. If I can stop the blow by and change to the 900024 plug or get mine modified I should be good to go. One other problem is leaking around the plug itself, which I can stop with a bronze thrust washer. Thanks guys for all your help. :yeah:
 
You may want to try bh209 in your gun before any major modifications. I have a krb7 that I added an oring under primer(had to buy and try several sizes) that has never had a hang or miss fire with no other mods. Now I know the other 2 weren't so lucky,but I have hunted at around o degres and no problems either on deer or touching off at end of day.I tested this gun and a hunterbolt I modified after leaving in car at -1o degrees overnight on 2 different occasions with instant ignition and dead on.No blowby with cci mag primers.
 
casper said:
Shawn T, I don't have a camera or for that matter computer savy to post pictures, but if you GOOGLE knight Revolution recall there are a lot of good pictures there. I think if I tap out the 2 top roll pins that plunger assembly will come out and I can look for a stiffer spring set up. If I can stop the blow by and change to the 900024 plug or get mine modified I should be good to go. One other problem is leaking around the plug itself, which I can stop with a bronze thrust washer. Thanks guys for all your help. :yeah:

Never thought to actually ask this, but have you tried BH209 yet in the rifle or just assuming it will not fire?

The KRB also uses the domed plug too so you may not "Have" to install the ventliner.

Here is another test for you to try before you start tinkering. Take a DRY patch put it on the jag of the ramrod and run that down the barrel till it stops at the breech plug (NO CHARGE) and leave it there. Place a little piece of tape on the rod even with the muzzle. Next put in a primed FPJ and while pointing in a safe direction pull the trigger, don't worry the rod is not gong to leave the barrel just don't point it at someone close. :wink: Now measure how far the rod moved up the bore. IF it only moves and half inch or so then you may have a good bit of leakage where it is not sealing well. IF it moves say 4 or 5 inches, then Like Stude283 said load up a charge of BH and try it.

When I first started working on my KRB7 I was just trying to get the thing to shoot clean in the action with 777. Smoke would roll out of the action of this rifle leaving the inside of the action real dirty. I was not trying to shoot BH209 then, but Hornet22savage was and was having issues reliable ignition. We found once we did the 2 mods both were not only clean in the action but even I could shoot BH209 with the Stock Knight Flashhole (Domed plug).

When I tried the above test I don't remember the rod moving more that about an half inch or so (Very little) and after the mods (O-Ring was the main fix) then that rod moved about 6 to 7 inches, indicating a much improved seal on the primer. :shock: The heavier spring was to maintain more forward pressure on the block under fire. Was it really absolutely needed, don't know but I like the heavier spring tension holding the block forward tighter to maintain that primer seal. The O-ring fix will not apply to the Revolution since it only can shoot the FPJ and can't shoot Naked primer. Are you sure that the block on yours is moving back under fire. I know that the block on those don't sit as high as the KRB. IF there is a gap between the action cutout and the block when it is in the closed/fire position you could try wedging something (Like a strip of stiff plastic or some compressed cardboard, strip of brass something that will not damage the action) in the cutout between the block and the back of the cut out to stop the blocks rearward movement. If it seals up better and it is much more clean then you know for sure that the block is moving under fire and allowing some leakage, IF it is still dirty, then a heavier spring by itself will not help. and you would need to investigate farther.

There can be a good bit of variation in one rifle to another and I personally think that Knights QC in the Revolution and KRB were getting a bit off by then. A good example here is since Stude283 only needed the o-ring in his KRB then the tolerance's on his rifle work to his advantage so that he did not need to go farther to get good ignition, whereas for me just installing the o-ring pushed the block to far back and then it interfered with the hammer, so I also had to deepen the pocket a bit to correct that. In My MK-95's there is .006 differences in the actions and plugs so that the new Brass cases I am now working with do not work between 2 of the same model rifles.


I would be real interested in seeing how far the rod moves in the current stock form. Try that and let us know.

As for sealing around your breech plug, have you tried using Teflon tape? If not try it before putting a washer down onto the flange in the barrel. If you look at the face of the plug you can see a "Ring" where it has sat on the flange down in the barrel. Start wrapping the tape so that you have overlap that you can press down onto the face of the plug covering that ring fully. It will help maintain a good seal on that plug face and the flange in the barrel. Once you have the plug wrapped use a finger nail in the threads and twist the plug so that you push the tape down into them. Then install it as normal.
 
The ramrod test shows a whopping 3/4" movement. One thing that makes me feel the primer plunger is moving back under fire is, the primer does bottom out on the breech nipple. There is a gap before the RPJ bottoms out on the nipple and no gap with an empty RPJ. So that tells me the primer is toughing the nipple before the RPJ. I had the firing pin and plunger out, now I just have to find a stiffer spring.
 
casper said:
The ramrod test shows a whopping 3/4" movement. One thing that makes me feel the primer plunger is moving back under fire is, the primer does bottom out on the breech nipple. There is a gap before the RPJ bottoms out on the nipple and no gap with an empty RPJ. So that tells me the primer is toughing the nipple before the RPJ. I had the firing pin and plunger out, now I just have to find a stiffer spring.

Is there a way to wedge something behind the block to make it stay closed? Those don't have an exposed hammer either do they?
 
I dug up 2 pictures online but they are a tad fuzzy. That trigger group looks to have a "Fixed" block that rotates down when the lever is released, probably what the pins you are talking about hold. Then there is an internal hammer inside of that trigger group. It looks like the only thing that really holds that block forward in the fire position is the small release lever that is located just behind the trigger guard when it is closed. If this is true then the spring you are talking about replacing is the hammer spring and not one for the block. If that is true replacing it might not help. :think:


This one shows the little lever that holds the trigger group in the locked position.



Is this correct on how that group works? Is there more than one spring in there? When in the closed/locked position does the group still move if you lift up on the trigger group lever on the trigger guard?

I don't know what the recall was actually for but have you had the recall performed on the trigger group?
 
There is a plunger, spring and floating firing pin in the block at the top of that trigger group in between the two roll pins. That's the spring I would have to make stronger, so the primer pressure won't push the plunger back. The recall was user error, people were closing the action with their booger hook in the trigger guard, Knight couldn't duplicate the problem when used correctly. No I did not send mine in as I like the way my trigger feels and I've heard horror stories of people getting their triggers back with a 10 pound pull.
 
Ok. I can't find a real good picture of the top of the assembly. Does this Plunger you refer to push forward on the FPJ/Primer?

Do you know if the whole assembly moves up and down any when it is up in the locked position?

By the way, what did the patch look like that you fired the primer on? How much was it burned through?

Many questions, see what you did you got me real curious. :lol:

That is a type of Rolling block too, not a falling block.
 
Yes the plunger is slightly larger dia. than a FPJ and it's flush with the housing until you close the action, that's where the spring pressure comes into play. As you close the action it compresses that spring. The patch was burnt black and started to burn a hole through it. I had no problem completely sealing my D.I.S.C. Extreme from "any" blowby. This design has got me working overtime. :lol:
 

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