Author Topic: parts layout  (Read 902 times)

Offline WonkyEye

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parts layout
« on: August 10, 2024, 12:55:35 AM »
I'm trying to wrap my head around the exact positioning of the barrel, lock, triggers and where the bolts will go.  Does Pic #1 look correct?  I marked the bent tang in white, bolt locations in red.  My fat fingers are in the way, but the front lock bolt location is just below the barrel where the web would be, rear lock bold would go through the breech bolt tang?flange? (not sure what that part is called below the tang)



Does the trigger sear location look correct in pic #2?  it seems ... off. 


the trigger spring pushes the rear trigger flag that high, which makes "y" between the trigger flags quite far, just about .75" from the pin for the front trigger. I'm afraid an unset trigger pull will be quite horrible, it will have to travel 1/4" just to contact the sear lever and will have to overcome the leverage (or lack of) to trip the sear.  and it also seems that being that high will cause the wrist to be quite thick.



Do I go with the layout as is?  Do I plan on filing 1/16" or 1/8" from the top of the trigger flags?  Is there another option?

Offline davebozell

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Re: parts layout
« Reply #1 on: August 10, 2024, 01:33:01 AM »
You need a book like “Recreating the American Longrifle” by Buchele.  It describes all the steps you need to take to get the layout correct.  There are several posts in the Tutorials here that will help as well.
« Last Edit: August 13, 2024, 03:17:32 AM by davebozell »

Offline rich pierce

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Re: parts layout
« Reply #2 on: August 10, 2024, 01:51:49 AM »
It’s very common to have to file some off the top of trigger blades. After all, they make them so customers can fit them to a variety of gun layouts.

I’m guessing you have the touchhole location figured out.

If needed there’s no problem with filing a half round slot across the bottom flat of the barrel where the front lock bolt will go. Depends on web thickness whether this is needed.

In general it looks like you’ve got this figured out. Trying to get the front lock bolt AND the tail if the lock where I want it takes some fiddling for me.
Andover, Vermont

Offline Steeltrap

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Re: parts layout
« Reply #3 on: August 10, 2024, 01:55:14 AM »
I agree with davebozell. You need a book. Spend the roughly $50 and read it. I purchased "The Gunsmith of Grenville" and it went a long way to help understanding a rifle build.

You're getting (IMHO) ahead of yourself by trying to align the parts with any specific dimensions. It's not bad to get the image in your head though.

Remember, it all begins with the barrel and the barrel inlet. Knowing web thickness, the breech plug depth in order to locate the flash hole. Then you align the lock pan with the flash hole, the front of the lock with the web, and the rear of the lock centered on the wrist.

I'm oversimplifying it a bit, but it's critical to get your barrel properly inletted as everything goes off the barrel.

Offline mikeyfirelock

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Re: parts layout
« Reply #4 on: August 10, 2024, 02:37:23 AM »
You’ve got the right idea.   Like several others have said…..get the book! Either one will be very instructive and complete.
For myself, I use the touch hole as my basis for locating everything else. I plan on a touch hole in the size of 1/16 - 3/32 ( others may use other sizes) and locating it ( the rear of the touch hole) aproximately 1/16 to 3/32 in. ahead of the breech face. ( I drop a rod down the barrel till it rests on the breech face, then mark the rod at the muzzle……then use the mark in the rod to mark the location of the breechplug face on the side flat of the barrel.   The hole touch hole center is then 1/16 ( or 3/32)
Plus 1/2 the diameter of the touch hole ahead of the breech face using this method.
Others will have other methods ( probably easier ) bu this works for me. Now
The lock placement is determined by centering the pan on this touch hole center . The rest of the gun then follows the lock placement.
Sounds complicated, but is actually very straightforward.   
Mike Mullins

Offline WonkyEye

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Re: parts layout
« Reply #5 on: August 10, 2024, 02:43:38 AM »
this book?







Offline Bill Raby

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Re: parts layout
« Reply #6 on: August 10, 2024, 04:54:36 AM »

Offline Bob Roller

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Re: parts layout
« Reply #7 on: August 10, 2024, 04:07:37 PM »
The angle of the tang screw IF it's a machine screw may be beyond the ability of a lot of the  builder to continue it thru the front of the trigger bar
Bob Roller

Offline Steeltrap

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Re: parts layout
« Reply #8 on: August 10, 2024, 06:12:20 PM »
The angle of the tang screw IF it's a machine screw may be beyond the ability of a lot of the  builder to continue it thru the front of the trigger bar
Bob Roller

Bob has a very valid point on this part of a build. If you make\use an alignment device as the fellow in the video had done, remember that the angle of the drill to the trigger plate may not be "square on". That being the case, the drill will have a tendency to "walk" when it contacts the trigger plate, and you can end up with an oblong hole. (Ask me how I know this)

There are several approaches to making sure this doesn't happen. As the guy in the video explains, flipping the piece to allow the hole to be "met in the middle" is a good way to do this.

If your starting through metal at a slight angle it may be best to use a center drill to start the hole and drill it deep enough for the point of your "final drill bit" to grab metal instead of the side of the bit grabbing metal first.

And if the trigger plate hole is at a slight angle, it's best to align the tap at the same angle as the hole when starting. I usually place the tap in my drill press (do NOT turn the drill press on) and place the TP on a drill press vice. Then lower the tap and turn the drill press by hand to get the tap started properly.

I hope this made sense and I hope it helps.

Offline WonkyEye

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Re: parts layout
« Reply #9 on: August 10, 2024, 07:37:17 PM »
Here is link to a video that might be helpful

https://rumble.com/v136jdd-lancaster-rifle-build-haines-part-23.html

Thanks, huge help!  Your video answers that last question and concerns in pic 2 and 3 about the single stage trigger pull and about the wrist thickness.

Offline WonkyEye

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Re: parts layout
« Reply #10 on: August 10, 2024, 07:40:45 PM »
The angle of the tang screw IF it's a machine screw may be beyond the ability of a lot of the  builder to continue it thru the front of the trigger bar
Bob Roller

Bob has a very valid point on this part of a build. If you make\use an alignment device as the fellow in the video had done, remember that the angle of the drill to the trigger plate may not be "square on". That being the case, the drill will have a tendency to "walk" when it contacts the trigger plate, and you can end up with an oblong hole. (Ask me how I know this)

There are several approaches to making sure this doesn't happen. As the guy in the video explains, flipping the piece to allow the hole to be "met in the middle" is a good way to do this.

If your starting through metal at a slight angle it may be best to use a center drill to start the hole and drill it deep enough for the point of your "final drill bit" to grab metal instead of the side of the bit grabbing metal first.

And if the trigger plate hole is at a slight angle, it's best to align the tap at the same angle as the hole when starting. I usually place the tap in my drill press (do NOT turn the drill press on) and place the TP on a drill press vice. Then lower the tap and turn the drill press by hand to get the tap started properly.

I hope this made sense and I hope it helps.
Thanks a bunch, I was confused by Bob Roller's meaning.  Drill bit walking makes sense.  I imagine the tang screw should be at a perfect 90° to the tang so the head sits flush, and I could see the angle in the trigger plate posing a problem if not drilled 1/2 and 1/2 as you suggest (and as demonstrated in the video)

Offline Bob Roller

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Re: parts layout
« Reply #11 on: August 11, 2024, 12:28:55 AM »
 This is not a problem if you have a milling machine or access to one.The "seat"to start a hole is easily established.I am so used to having these machine tools I forget many do not.
Bob Roller

Offline Steeltrap

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Re: parts layout
« Reply #12 on: August 11, 2024, 12:44:27 AM »
This is not a problem if you have a milling machine or access to one.The "seat"to start a hole is easily established.I am so used to having these machine tools I forget many do not.
Bob Roller

Yes Bob.....you're such a showoff!!   :o ;D ;D

Offline smart dog

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Re: parts layout
« Reply #13 on: August 11, 2024, 01:07:41 AM »
Hi Wonkyeye,
I urge you not to lay out your parts like that.  MAKE A DRAWING AND WORK IT OUT ON PAPER FIRST.  With respect to fitting the set triggers, don't use that notion of positioning the sear where the trigger bars cross.  I have no idea where that notion came from but it makes no sense whatsoever.  Your triggers are designed to fire the gun set or unset.  Below is a post I wrote a while ago.


"Set triggers can be a pain but let me suggest how I proceed.  I assume your triggers are double lever so the gun can be fired set or unset.  The first important factor to understand is the rear lever only needs to be tall enough to hit the sear of the lock when it is activated by the spring and front trigger.  It does not need to be any taller.  When not set, the rear lever angles upward and may interfere with the lock engaging half and full cock.  Grind it down as far as necessary to prevent that from happening.  Next, the rear lever can hit the sear anywhere along its length and still do the job.  Therefore, ignore it when positioning the triggers in the stock except to make sure it will hit the sear even if just the farthest forward part touches the sear. Concentrate on positioning the forward trigger and try to place it as far back as you can relative to the sear on the lock but still have the rear lever hit the sear.  This is where you will find many commercially made set triggers are stupidly designed.  They often grind the front of the rear lever at an angle, which means you have less top of the lever reducing how much you can position the triggers backward and still have the rear lever engage the sear.  The front trigger should be positioned much like a simple trigger such that the sear hits it about half way or a little less from the front.  However, you cannot allow it to touch the sear, thus have no creep, because it has to pop up when the rear trigger is set.  Therefore, you cannot eliminate all creep in the front trigger when not set but you can still achieve a light trigger pull and reduce that creep by positioning where the sear bar on the lock hits the forward trigger as far forward as possible.  Let me mention a feature I add to all my set triggers.  Take the triggers out of the gun and set the rear.  You will see that as the front trigger lever engages the rear lever, the both pop up a little.  This is the clearance you need below the sear to prevent interfering with the lock.  If you replace the anemic wire front trigger springs commonly found on commercial triggers with a little heavier spring steel, you will reduce that pop up to only what is required for the engagement to catch."

dave       
"The main accomplishment of modern economics is to make astrology look good."

Offline Randall Steffy

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Re: parts layout
« Reply #14 on: August 11, 2024, 02:24:22 AM »
Another "copy and paste" for my longrifle notes. Thanks Dave!

Offline WonkyEye

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Re: parts layout
« Reply #15 on: August 11, 2024, 12:06:51 PM »
Thanks for clarifying, Dave.  Big help, I thought I had something wrong, this makes much more sense now. This was me trying to conceptualize the relationship of the parts so I can make the drawing, but it seems I've just alarmed everyone and given the impression I'm trying to skip all that, which is not the case.

Offline Tim Crosby

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Re: parts layout
« Reply #16 on: August 12, 2024, 03:25:59 PM »
 This may be of some help, scroll down to page 16: https://americanlongrifles.org/PDF/tutorial.pdf

   Tim C.