First Gun Build Questions

[jdkerstetter]

I should just tell ya to go back and read the previous post but will save ya the trouble. :shake:

You should've already transferred the mark on the dowel to the barrel by laying it along side the lock side flat and using a Sharpy or some such.

If you did everything right the mark on the dowel is the distance from the muzzle to the face of the breech plug. So, you will measure 3/16" forward...or toward the muzzle....of that mark and you will put a mark there indicating where your vent will eventually be....3/16" ahead of the breech plug face.

So, when you square up the breech end of your barrel inlet you will want to set your barrel back...inletting as you go...until the mark for your vent lines up with the pan on your lock plate.

I hope that's all clear. Enjoy, J.D.

 

Nope... I hadn't transfered that to the barrel, but I will do that tonight. Thanks for the reminder.

Things to do tonight:

• Open up barrek channel a hair so barrel is not so tight
• Transfer mark on dowel (3/16" form breech) to barrel
• Square up end of barrel channel with barrel
• Reinstall breech and bevel breech plug
• Make sure mark on barrel aligns with pan, if not, inlet a bit until it does.
• Inlet tang???

 

[jdkerstetter]

Nope... I hadn't transfered that to the barrel, but I will do that tonight. Thanks for the reminder.

Things to do tonight:

• Open up barrek channel a hair so barrel is not so tight
• Transfer mark on dowel (3/16" form breech) to barrel

• Transfer mark from dowel to barrel then put another mark 3/16" forward of that mark for the vent.
  

  [*]Square up end of barrel channel with barrel
  [*]Reinstall breech and bevel breech plug

  Don't install the plug until you've done the next step first. You want the mark for the vent lined up with the center of the pan and the barrel firmly seated against the back of the channel before you reinstall the plug. This step is critical....if there is a gap between the back of the barrel and the end of the channel the barrel can move back from the recoil when you first fire the gun. That can be be a big problem.
  

  [*]Make sure mark on barrel aligns with pan, if not, inlet a bit until it does.
  [*]Inlet tang???

Don't forget to put some draft on the tang as well as the breech plug bolster. The angle should be the same on both sides and one end to the other....look in the books.

Enjoy, J.D.

 

Thanks for the clarification. I had though the breech plug sat against the back of the barrel, but in looking at some pics online (I don't have my book with me) I see that is not the case. So make that nice and tight first.

You comment about "Transfer mark from dowel to barrel then put another mark 3/16" forward of that mark for the vent." doesn't make sense though. Then I would have two marks on the barrel. One that is 3/16" forward of the breech end (which I thought was where the vent hole will go), and then another that is 3/8" forward of the breech plug (3/16 + 3/16 = 3/8 right?) which is used for what??

 

[Zonie]

You should end up with a mark that is the same distance from the muzzle as the face of the breech plug.

You should also have a mark that is 3/16" closer to the muzzle than the breech plug face.

The closer to the muzzle mark is the location for the touch hole liner.
It is the mark that you will be trying to line up with the center of the locks pan.

At the rear of the barrel channel (towards the stocks butt) you will probably notice that the channel has two radius's left from the milling cutter that made the channel.

As you slide the barrel aft (towards the butt), the rear of it will hang up on these radii.

Those are the first thing you need to remove and you do this with a razor sharp chisel.
I suggest using a 1/4", 5/16" or 3/8" wide chisel to do this.

When I say "razor sharp", I mean exactly that.
The cutting edge should be sharp enough to shave with.
A good test for this sharpness is to lay the flat side of the blade (not the beveled side) on your fingernail. Then, raise the blade about 5 degrees so it is just touching the nail with the cutting edge.
Lightly push the chisel in the direction that should cut into the nail.
If it instantly starts to cut in, stop. Your chisel has passed its sharpness test.

If it doesn't cut into the fingernail you should sharpen it.

The reason for using a narrow chisel on this wide area is because it gives you better control of where it's cutting and how much it is cutting.

Do NOT try to remove all of the extra wood with one cut.
Take several cuts, shaving off just a thin curl of wood.

The chisel must be held exactly perpendicular to the barrel channel and square with the rear of the barrel.

Work both sides of the channel, testing the fit of the barrel often.

You should use some inletting black on the rear surfaces of the barrel to show you where it is hanging up and which side to work on next.

Have fun and don't cut the area wider than the barrels width. A gap here looks pretty ugly.

 

Well, I think I may have messed up. I took the dowel, and marked 3/16th from the end to indicate where the touch hole should go. I then made sure the barrel channel was not as tight as it was and then started to inlet. Used a 1/8" chisel that was nice and sharp, but I think I may have taken it back too far. The mark where the touch hole is supposed to be now is in line with the rear edge of the pan. I also am having issues with getting that mortice flush.... meaning, the breach of the barrel is making contact at the bottom, but there is a gap at the top (very slight... maybe 1/16 - 1/8"). I started to get frustrated with it last night at that point, so I just walked away and will figure it out tonight.

I'm not sure how I missed the mark by that much as I took a look at where everything was and made a mark on the top of the breech location as to where I needed to remove wood up to, and never exceeded that line.

But, the fact remains, the hole location is going to be too far back. Is this a big deal, and what tips can be given on how to get everything level? I know I need to use the blackening stuff, but not much is transferring at this point. This is a huge test of my patience at this point and I'm glad I walked away last night.

Also, on the chisels, what is the proper angle that they should be sharpened at? 25 degrees? I have a very nice Veritas so getting the correct angle is not an issue, but wanted to know what the recommend angle should be.

Thanks again for all the help... I feel like a real PITA though.

John

 

[jdkerstetter]

...Thanks again for all the help... I feel like a real PITA though. John

You are!!! :rotf: :rotf: :rotf:

All right, let's move on.

Check everything again when you get home. Before you remove any more wood ensure that you marked your vent location correctly. Check and triple check. 3/16" from the breech plug face. If you aren't clear on how to measure this, now is the time to ask!

Many times after one walks away in frustration and goes back it's not as bad as it seems. Walking away was a great idea, by the way. Happened to me last night too....must be the moon phase. :hmm:

First, an 1/8" chisel is way too narrow for this work for me. When removing wood and attempting to keep the surface level you want as wide a chisel as you can get into the area. You have less chance of gouging up the work this way also. Do you have any experience with wood planes? You wouldn't use a 6" block plane to level a table top when you have a 14" jack plane?

Now, as Zonie said, you should've been working the back bottom of the channel first. There would've been a rounded/concave area there where the mechanical cutter finished doing the barrel channel at the shop/factory. That should've been squared up with the breech end/back wall of the channel before doing any setting back of the barrel. I like to use a chisel that is as close to the width of each barrel flat as possible to do the cuts here.

After you've squared up the bottom of the channel to the breech end then the barrel should slide all the way in and should be flush up against this back wall. That is when you will see how far back the barrel needs to move by measuring the distance between the vent mark on the barrel and the center of the pan on the lock.

After you know how far back you have to go then it's just a matter of paring away wood from the vertical back wall/breech end of the channel until the barrel moves back far enough to align the vent mark and pan. To do the majority of the cutting on this back wall I like to use a chisel as close to as wide as the breech end of the barrel as possible, cutting straight down. You will have to use narrower chisel or a skew chisel to do the bottom of this wall where it meets the bottom flats of the mortise.

All of this work should procede slowly and carefully. As I stated in a earlier post, a good fit in this area is critical.

Chisel bevel angle? For bench chisels the common bevel is 25 degrees with a 30 degree micro bevel and this works for me. There is a ton of information on sharpening on the web....google it.

Good luck. Hope it's not as bad as it seemed last night....it seldom is, if that helps. J.D.

 

Thanks JD.... But I guess the question still is this. If the proper location for the vent is behind the pan, there is no way to move the lock back since it was preinlet. Can I safely bring the vent hole forward (and I don't know the exact measurement yet as I didn't measure it last night, but if I remember correctly, it was about the trailing edge of the pan... maybe a little bit further back). I know I have to center the hole with the pan, but if let's say the hole is now 1/4" away from the breech plug is that too much? I know 3/16" is the ideal but up to what point is okay for 50 cal?

Also, on the chisel bevel... do you recommend a micro bevel?

 

[jdkerstetter]

I edited the first part of my post above about the vent hole.

Don't worry about anything else until you make sure the mark for your vent is in the right spot.

Don't get ahead of yourself. If you did indeed miss, then you will probably have to square up the back wall of the barrel mortise where it is and you're vent will be a little farther forward or ideal. Yours wouldn't be the first one.

Can you post photos??? That would help us, help you. J.D.

Yes, I micro bevel my bench chisels and plane blades.

 

Okay, I see the edit, but then you say "don;t worry about anything until your mark for the vent is in the right spot". Well, the mark is in the right spot on the barrel, but when placed in the barrel channel, that is aft of the pan.

I'll get some pictures tonight to better illustrate.

If I understand what you wrote though, I MUST square up the back of the wall... so take care of that and deal with the rest? When I square that up, I'm sure it will pull the barrel a little bit further back... damn. I feel like an idiot.

 

[jdkerstetter]

Yes, the back wall must be square with the channel so you get full contact between it and the breech end of the barrel.

This contact area is what prevents the barrel from moving backwards in the gun when you fire it. If you don't get good contact during this phase of the build, you will when you fire it...then your vent really won't line up...or anything else.

Don't sweat it now. Nothing you can do 'til you get home and start checking everything out.

Do you remember how long the threaded portion of your breech plug was, by chance?

Just enjoy, J.D.

 

JD... in a Previous Thread I had measured the threads at 0.611" and the inlet for the plug at 0.625". What are you thinking?

 

[jdkerstetter]

Finish your day. Go home and remeasure everything. Take some pictures and let us know what's what. I'll be on later tonight....as will Zonie, I'm sure.

Enjoy, J.D.

 

Okay... I'm in a bad mood, so no working on the gun tonight... I'll just screw something else up.

But, I do have photos and numbers.

- The breech bolt length is 0.606".
- The line is off by 0.075" from where it should be (first picture)... not as bad as I had thought.
- The gap at the back of the muzzle is less than 0.020". I say less than as I have a small steel micro ruler than I can't get between the gap and that is 0.020" according to my veneer micrometer.

So questions...

1) Is the gap (

 

[jdkerstetter]

Good evening.

OK, first question is, are you sure that you're mark is 3/16" a forward of the breech plug face?

Now it's good news, bad news time so hang on.

Good news is that if your mark is accurate you will still be OK....not ideal but OK....even when you square up the back of the mortise to close that gap. And yes a crankneck chisel would be ideal if you have one.

Next question, in the pictures is the barrel bottomed out in the barrel channel, all the way in?

If so then it's time for the worse news. Now, I hope I'm wrong but it doesn't appear so from your pictures. That little crescent shaped shaddow above the pan of your lock? Is that the bottom of the side barrel flat? If so, that won't fly. The lock bolster has to be up on the side flat. That gap will allow your prime to dribble down into the lock mortise. Powder in there hit with a spark will blow the lock right off the gun....seriously.

I've heard of this happening on precarves, it means either the lock was inlet too low or the barrel not deep enough. There is only one solution and that's to lower the barrel until the lock bolster is resting on the barrel side flat completely...about half the flat or a hair under will be covered by the bolster when all is right.

I hope I'm wrong and you just don't have the barrel clamped down. J.D.

 

[Zonie]

First, a dog legged chisel won't be easier. Forget that.

I'm sure glad you exagerated the gap at the rear of the barrel. 1/8" would have been way too much.
.020 is easily fixed.

You MUST fix the stock so that the .020 gap is gone.
As was said, the full recoil of the barrel is absorbed by the wood at that location and a gap means there is very little support.
Stuff like that will crack the stock when the gun is used.

Now, looking at your photos and your numbers it does look like you might have the mark for the vent hole in the correct place but as jdkerstetter said, this isn't a show stopper.

After the barrel is fully seated you are going to relocate the touch hole to align with the center of the pan.

From your photos, this will only be about 1/16" ahead of the recommended place and it will be close enough to the face of the breech plug that any powder charge greater than 40 grains will keep the patched ball ahead of the vent hole.

In other words, it will work fine for everything except a light squirrel load.

 

[jdkerstetter]

Crankneck yes, dogleg not so much.

I have some patternmaker's crankneck chisels and gouges that I like for barrel channels. They lay nicely on the flats of the mortise with the handle up. With the inside bevel they pare wood nicely from that round out at the bottom of the breech end.

Enjoy, J.D.

 

[fosters]

Hey pbd,
I was like you scared I would mess up a $300 dollar stock or barrel or both. Still am sort of, but over the last few months I have learned that darn near any mistake can be fixed, and in most cases no one will know but yourself.

You did the right thing tonight by walking away. Just relax, this is suppose to be fun. J.D., Zonie, and all the other builders here will get you through. Great group here so no worries.

fosters

 

Thanks for the tips gang. Good catch there JD on the barrel flat... I hadn't even looked at that. I will take a look later today to see if I just didn't have everything lined up or what.

I'm going to recheck the dowel as well. I'll remmark it (or double check my mark for depth with the breech plug installed) and then double check my mark.

Now... dogleg vs crankneck...what's the difference? The look exactly the same to me online.

 

Okay... I just checked the gun and here is what I see. There is a bit of a gap beneath the pan, but not as big as was seen in the picture. I must not have had it fully seated. But, there is a gap. I took out the barrel and looked under it and there is some rough wood there. I can't get my chisel in there to shave it out, but I was able to get a 1/4" flat tip exacto knife in there and made short work of it. I haven't checked it just yet, but I hope that will solve the problem.

I also remeasured the dowel and the spot on my barrel, and the mark on the dowel was correct, but the mark on my barrel was a bit to far aft (good news). I'll square up the breech area and then reassess where I am at.

I'm not sure how much work I will get on this today as I have a funeral to attend and tonight is date night with my wife, but at least I have a good idea what needs to be done.