Hi all,
First Post! Hopefully it doesn't sound like a totally ridiculous question...
I have a Colerain .62 barrel that I am trying to make a breech plug for but am totally stuck. I will be honest, this is only the second barrel I have ever breeched and the first one had a plug from TRS that just needed some minor fitment.
To explain the issue with the new one, I bought a 3/4 UNF bolt and trimmed it to the correct length. I have followed every thread and video I can find and have been using prussian blue and been filing, fitting, filing, fitting. I get to a point where no more prussian Blue shows on the plug. Presuming it was due to the blue running out, I top it up, screw in and some more shows up (which I am now thinking is the raised areas of blue in there) and then I end up in the same position, I end up with no contact, anywhere.
Now I have looked inside the barrel and also at the plug from my other Colerain barrel. There appears to be a 'step' in the shoulder and thread inside the barrel and on the breech plug. The thread is interrupted and inside the barrel, there is a little step up. On the fitted barrel, I marked the plug and barrel at the position of this step and found that it matches when the plug is in.
My question is, could this be what is causing the new plug to not make contact? Is it the thread not matching up/indexing in the same way, do I need to cut a step in the thread on the plug like the one from TRS and if so, how the heck do you calculate where to put it?? Or, do I just keep doing what I'm doing, but the bolt is now too short. It's like I'm just making it shorter and shorter and something is stopping the face from making even contact.
I have attached a picture of the two plugs, one showing the interrupted thread (at the top of the plug in the picture), the other the bolt that I have been filing away at for 2 days.
Please excuse my ignorance with this. Total amateur here and looking for guidance.
Thanks in advance,
Jason
First Post! Hopefully it doesn't sound like a totally ridiculous question...
I have a Colerain .62 barrel that I am trying to make a breech plug for but am totally stuck. I will be honest, this is only the second barrel I have ever breeched and the first one had a plug from TRS that just needed some minor fitment.
To explain the issue with the new one, I bought a 3/4 UNF bolt and trimmed it to the correct length. I have followed every thread and video I can find and have been using prussian blue and been filing, fitting, filing, fitting. I get to a point where no more prussian Blue shows on the plug. Presuming it was due to the blue running out, I top it up, screw in and some more shows up (which I am now thinking is the raised areas of blue in there) and then I end up in the same position, I end up with no contact, anywhere.
Now I have looked inside the barrel and also at the plug from my other Colerain barrel. There appears to be a 'step' in the shoulder and thread inside the barrel and on the breech plug. The thread is interrupted and inside the barrel, there is a little step up. On the fitted barrel, I marked the plug and barrel at the position of this step and found that it matches when the plug is in.
My question is, could this be what is causing the new plug to not make contact? Is it the thread not matching up/indexing in the same way, do I need to cut a step in the thread on the plug like the one from TRS and if so, how the heck do you calculate where to put it?? Or, do I just keep doing what I'm doing, but the bolt is now too short. It's like I'm just making it shorter and shorter and something is stopping the face from making even contact.
I have attached a picture of the two plugs, one showing the interrupted thread (at the top of the plug in the picture), the other the bolt that I have been filing away at for 2 days.
Please excuse my ignorance with this. Total amateur here and looking for guidance.
Thanks in advance,
Jason
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