Semisane

ITEM - In my first try with Blackhorn in the Mustang using a .25 ACP breechplug and small pistol magnum primers I had delayed ignition on every shot and several failures to fire.

ITEM - In my second try using a 209 breechplug and CCI 209 primers I had failure to fire with the first two primers I popped. The firing pin broke on the third try, ending the test.

ITEM - I've fired 15 shots with Blackhorn and CCI 209 primers out of the Omega X7 with no ignition problems.

FACT: The Omegabreech plug is slightly longerthan the Mustangplug. A very small difference, but still longer.

FACT: The flash channel in the Omega breech plug is a lotsmaller than the flash channel in the Mustang plug.

QUERY: What the heck is going on?

Here are the two plugs - Omega on the LEFT, Mustang on the Right.








So, I got curious and did a little measuring. The measurements shown in the (amateurish) diagram below may not be exact, but they are pretty close.



Note that the flash hole on the Mustang plug - though almost twice the diameter of the Omega plug - is almost four times longer.

Now I'm wondering if I'll ever get Blackhorn to work well in the Mustang. Hey, maybe that's a good thing.

sabotloader

Semi

But! the TC 'Speed Breech' is a lot longer than either of these two plugs and they are shooting the heck out of BH with the Triumphs...

cayugad

It really sounds like you have a rifle in which BlackHorn 209 will not work and a different rifle that it works just fine in. When you were using the small rifle primers ... did you shoot Goex?

ronlaughlin

What if you drilled an 1/8" hole for a ways into the flash hole of the Mustang plug? That would make it look some like the Omega plug. Would be hard on the drill if the plug is stainless. Need lubrication and one of them drills made of titanium or some such thing.

Semisane

Is that so, Sabotloader? Curiouser and curiouser. I'd love to see a cut-away diagram of the speed breechplug.

Semisane

Cayugad, I've been using small rifle primers (non-magnum) in the Mustang for over a year. They ignite T7, Pyrodex, and GOEX with no problem at all. In fact, I don't think I've ever had a misfire or hangfirewith them. What's interesting is that the small rifle magnum primers DID ignite the Blackhorn 8 out of 10 times, although with a hangfire every time, but the two 209 primers did not.

Ron, I am considering modifying that plug, or even one of my two .25 ACP plugs to look something like the Omega plug - even to the extent of getting someone with a lathe to dish the face of the plug. Do you suppose there would be any danger in that?

sabotloader

Semi

ronlaughlincomment made take a second look at you drawing again. I did not notice look at your drawing that well.

I divide the BP into 3 areas.... the primer cup - the flash channel and theflash hole. I did not recognize the fact that you really do not have a flash channel per say.... you have a flashhole that extends the lengthfrom under the primer cup... that might be a big problem. So my next question is what about the 25ACP BP is there a flash channel or just a flash hole? I am thinking a flash hole again...

Did you look at my last post in your other 'Mustang Down Thread' I posted a couple of pics of breech plugs. Look how long the 'speed breech' is....

http://www.huntingnet.com/forum/tm.aspx?m=3328417&mpage=2&=#3329215

If you are up for an experiment when you get your gun back... duplex a load.... load in 10 grains of T7 or even Goex, then drop in 90 grains of BH compress the load with sabot/bullet combination and shoot that. If it shoots and I think it will - that would be a definite indication you are not getting enough heat through your flash hole to ignite BH but it will ignite the sub charge which ignites the BH.... If it doesn't shoot you will then know that the problem is compression leakage either out the BP or by the load...

What do you think?

LaneNebraska

Just drill about half way thru the plug , from the primer side, with the 1/8 drill bit and you'll be all set I'd say
Use some 3-in-1 oil as you drill it out, for a good smooth cut.
And keep the plug fastened tight, BH209 needs a nice tight seal all around.


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Semisane

Good thoughts Lane and Sabotloader. Pretty much along the same lines as Ronlaughlin suggests.

I've pretty much resolved to go that way, probably with both a 1/8" flame channel from the primer side and a deep dish on the face of the plug, separated by a 3/16" long flash hole. Fortunately, I have a buddy with a lathe. I'll probably have plenty of time to get that done before the receiver assembly comes back from Dixon's.

ronlaughlin

Seems like i remember someone here or elsewhere getting a breech plug designed for BH209, to test, from Knight. Did the photo of the plug show a flat face? Perhaps the concave face isn't critical for BH209 ignition.