Author Topic: Stock Offset Question  (Read 5709 times)

mjm46@bellsouth.net

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Stock Offset Question
« on: August 14, 2011, 05:34:54 PM »
I'm getting stuff together to start a new build that I plan on keeping. Barrel is a Rice 50 cal  Swamped B profile 44". Lock is a Chambers Deluxe Siler Flintlock. Style will be JPBeck with a Whaletail Brass PB. I'm hoping to get a stock blank this weekend at CLA.

My question is about offset. I have Alexanders book, and The American Longrifle. He seems to indicate that the offset starts at the point of the wrist where the comb begins. I also recall seeing others recommend that the offset starts at about the point of the tang screw. Can anyone narrow this down to a more exact point, or doesn't it matter much?

Offline Jim Kibler

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Re: Stock Offset Question
« Reply #1 on: August 14, 2011, 06:04:34 PM »
With reasonable cast-off amounts, it isn't necessary to carefully consider where the cast-off begins.  Just blend it and shape in a visually pleasing manner through the wrist area.  Careful layout doesn't really help shaping the wrist area since it is very sculptural and organic in form.  Just blend things in and make it look good in the shaping process.  I'm sure this isn't very clear, but it's about as good as I can do.

Jim

Offline D. Taylor Sapergia

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Re: Stock Offset Question
« Reply #2 on: August 14, 2011, 06:11:06 PM »
I know what you are saying Jim.  I try to maintain a centre line, no matter where the offset begins, coming back to restore it as the shaping continues.  Make sure you continue it along the bottom of the stock as well.  You don't want to end up with the tang off to one side of the comb, or more wood on one side than the other, would be a better description.
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Offline Habu

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Re: Stock Offset Question
« Reply #3 on: August 14, 2011, 06:29:19 PM »
. . . and make sure you layout your top and bottom centerlines from the same point of the same side of the stock.  I've heard that if you layout the top line from the lock side, and the bottom line from the patchbox side, you might discover that your stock has a little "twist."

Or maybe it's just me who makes mistakes like that . . .   


Offline flehto

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Re: Stock Offset Question
« Reply #4 on: August 14, 2011, 11:47:58 PM »
Perhaps some more experienced builders will chime in on my question. I usually start the castoff halfway between the end of a normal length tang and the comb dropoff and usualy use 3/16" offset. So the trigger guard fits in a straight line on the toeline, I tilt the buttplate toe  back towards the bbl centerline and end up w/ a straight toeline that doesn't have any castoff. Is this HC and does anyone else do this? Sometimes not all the castoff is eliminated on the toeline but most of it is. Thanks for any input....Fred
« Last Edit: August 14, 2011, 11:50:33 PM by flehto »

mjm46@bellsouth.net

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Re: Stock Offset Question
« Reply #5 on: August 15, 2011, 09:43:20 PM »
Let me see if I got this right. No actual rules or formula, just bend it. ???

Offline Dr. Tim-Boone

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Re: Stock Offset Question
« Reply #6 on: August 15, 2011, 10:49:49 PM »
Well, the cheek-piece is supposed to fit the owner's face/neck/shoulder architecture to allow the eye to easily line up on the sights.......given the size and shape of the owner...that gives you one place to begin... then it is like Jim says make it look nice..... Just keep checking top and bottom center lines and where your tang is pointing..... it should be a pleasing bend.
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Offline Don Getz

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Re: Stock Offset Question
« Reply #7 on: August 16, 2011, 01:52:20 AM »
If you are going to the CLA show, check out the Frank/John House rifle on my table, it has a lot of castoff..............Don

Offline smylee grouch

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Re: Stock Offset Question
« Reply #8 on: August 16, 2011, 05:03:23 AM »
May be you need some cast off with a Beck style gun, may be a 2" wide butt, but would you need any cast off with a slim styled rifle with say a 1&1/4 or 1&1/2" wide butt?     Smylee

Offline Habu

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Re: Stock Offset Question
« Reply #9 on: August 17, 2011, 04:59:29 AM »
I knew I'd seen some mention of an actual measurement for starting castoff, but it took a while to find the right book.  The first step is to mark the actual centerline of the stock on both top and bottom. 

In Recreating the American Longrifle (the Buchele/Shumway/Alexander version), on p.61, it recommended to start the castoff along the comb "at a distance of 5 inches behind the breech end of the barrel."  The other end of the castoff-centerline is set at the butt, offsetting the amount of castoff desired.  Then you just strike your new (offset for castoff) centerline.

On the bottom (toeline?) of the rifle, you lay out the same offset at the butt, with the other end of the offset line somewhere around the rear end of the triggerguard. 

Hope that helps.

Jim


mjm46@bellsouth.net

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Re: Stock Offset Question
« Reply #10 on: August 17, 2011, 05:43:16 PM »
Thanks All! I think I got what I was looking for.

Offline John Archer

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Re: Stock Offset Question
« Reply #11 on: August 18, 2011, 01:06:41 AM »
May be you need some cast off with a Beck style gun, may be a 2" wide butt, but would you need any cast off with a slim styled rifle with say a 1&1/4 or 1&1/2" wide butt?     Smylee

I don't put any cast off on rifles with narrow butt plates......other's mileage may vary.

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Offline AndyThomas

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Re: Stock Offset Question
« Reply #12 on: August 18, 2011, 01:43:44 AM »
On the thick butted (2" to 2 1/8") rifles I build, I use 1/4" castoff (on both the top and bottom). The pivot point on top is the center of the rear of the tang. On the bottom, it's the center of the rear of the trigger. These points do NOT line up. This doesn't really matter, though, because of all the blending, as Jim Kebler points out. I set the trigger and front finial of the guard on the centerline of the barrel, and the rear finial along the castoff line, which means the guard bow is askew of the trigger. Nobody will notice it. Nonbuilders don't even notice the castoff until you point it out to them.

Andy
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