Minor prob with my GPR kit stock

[noahmercy]

Well, I finally got my stock all sanded down and my furniture prepped for browning! ('bout flippin' time...) I trial fitted my barrel and tang to the stock to check for any gaps or misalignments.

Well, the wedge holes and underlugs don't quite meet. It looks like I need to relieve the stock behind where the flat back of the tang mates with it to allow the barrel/tang to slide straight back a little. (Please forgive me if my nomenclature is improper...I am still learning.) I figure the proper tool for getting some of this wood out while keeping the surface flat would be a scraper. (Correct me if I'm wrong...that's the whole point of this post, after all.) What size should I be looking for and what style? Also, who makes a good one? I like to buy good quality tools. I've never regretted spending a bit more in the beginning...using a finely made tool is a pleasure. I know I may need to inlet the tang a little and that's no problem...I have tools for that. I'm just wondering how to get all the important holes to line up.

Also, if I gouge the wood or get it uneven, what do y'all recommend to use as a leveling agent? I have Acra-Glass Gel and Marine-Tex. I assume that since that surface is what holds 99% of the recoil, there should be a perfect mating of tang and wood at that point.

Well, master charcoal-burners I await your profound advice and thank you in advance. Your knowledge and willingness to share it is why I'm building a frontstuffer. I guess you could say your enthusiasm is contagious (gun cooties :shocking.

:thumbsup:

 

[vradin]

I make my own scrapers from flea-market handsaws. Cheap and easy to do, but if you're in the market to buy pre-made tools then Lee Valley tools is one of the best I've found for quality and service.

No, I don't work for them (wish I did) but have been more than satisfied with the tools I've gotten and the service behind them too.

 

[AZ-Robert]

It looks like I need to relieve the stock behind where the flat back of the tang mates with it to allow the barrel/tang to slide straight back a little.

You mean the rear face of the breech plug? (an inch or so wide)

 

[noahmercy]

Well, the GPR has a hooked breech screwed into the barrel that hooks into a separate tang which stays on the gun when the barrel is removed. The tang assembly has an octagonal section corresponding to the barrel that fits down in the barrel channel with a tang that protrudes back over the wrist of the stock. The rear of the octagonal portion is what I'm looking to set back. (I guess on guns with breech plug/tangs integral with the barrel, it would equate with the rear of the breech plug.)

That's probably clear as mud... :crackup:

And I'll give the Lee tools a look. I don't have facilities for easily making my own tools (or modifying existing ones) and I do very little woodworking, so buying pre-made will be the way I go.

:thumbsup:

 

[AZ-Robert]

That's probably clear as mud...

Nah, I got it ::

So, you're needing to remove wood from the stock's barrel channel where this spot of this part here backs up against it, eh?

I'm thinking one of the builders here can help you out.... I was just trying to get a clear image in my head of what is going on. Kinda eyeballing that GPR kit myself, or maybe something else if I can find someone close by to look over my shoulder once in a while.

 

[Connelley]

When you say the wedge holes and underlugs don't quite meet, what are you saying? 1/4 in.,1/64 in., a whole bunch? If the difference is small, perhaps you could widen the wedge inlets to the rear enough and reposition the wedge plates.

Connelley

 

[noahmercy]

You nailed it, AZ! (Nice visual aid, BTW.)

I've had a few problems with my kit due to poor quality control on this gun. If I had it to do over again, I'd probably buy a factory complete rifle and strip it down and refinish the metal and wood. (It'd be less work than what I've put into this one. :no From what I've heard, though, my situation is unusual...most of the kits require less effort than mine.

Thanks, pard. :thumbsup:

 

[noahmercy]

How do, Connelley. It looks like about 1/16". I'd thought about moving the wedge plates back, but upon further inspection, the hammer/nipple geometry will also require setting the barrel back a tad, so I have no choice but to remove a little wood from that area.

:thumbsup:

 

[Zonie]

I'm still trying to make sure I understand exactly where you need to remove the wood but I'll make a few guesses.

If you need to move the metal tang block aft, you will be cutting across the end grain of the wood.
My experiance with scrapers is they don't cut end grain very well. They just sort of rough it up a bit.

To cut across the end grain you really need a very sharp chisel. When I say very sharp, I mean sharp enough to shave with. IMO, it should be about 3/8- 1/2 inch wide.

Cutting downward into the back of the barrel channel, you will have to keep the chisel perpendicular with the barrel channel and the first inclination is to just place the chisel edge where you want it and hammer it down.
This of course is the wrong way to do it (IMO).
If you have a small "square" (or even a large one) place it into the barrel channel with the blade sticking up. Use this as a visual guide to keep the chisel pointed in the right direction.
position the cutting edge so it will be cutting about 1/64 of wood and push it down into the channel. It should shave the wood off. If you must use a pounder, use the smallest one you have and just tap the chisel downward.
(I prefer to use a chisel about 1/2 inch wide so it's not cutting both sides at once. Because it is cutting less, less force is needed to make it cut so it is easier to control what it is doing).
Basically, cut one side, then the other, then try the fit.
If it needs more wood removed, then repeat the procedure.
Check the fit often.

If your moving the tang much, be sure to check the rear of the tangs fit with the wood before taking off any wood from the barrel channels face where the metal block fits. Sometimes, this is the area that is holding the block forward.

If you are talking about the wedge pin holes needing elongating, use a narrow chisel or a file to elongate the holes.

If the protruding "Hook" is what is hanging up and keeping the barrel from fitting back against the metal tang block, just use a 1/4 wide chisle to remove the wood behind the block where the hook wants to live. This cut does not have to be real precision but cut and check often. There's no reason to remove any more wood than necessary here.

I hope I guessed right and my thoughts help you.

 

[noahmercy]

You're spot on, Zonie! Thanks for letting me know about using a chisel on the end grain as opposed to a scraper...that'll help keep me out of trouble. I have a really good set of chisels (and a 2 ounce brass hammer if the chisel needs a little encouragement), so I can do the work right away.

BTW, I checked for any other obstructions to the aft movement of the barrel/tang, and it really is a little extra wood at the back of the barrel channel. The fit of tang to wood there is admirably and unbelievably tight...I hope I can get it as nice after removing what needs to come out. :winking:

Thanks, Zonie! :thumbsup:

 

[jbrent]

I just finished a GPR kit and had the same problem. It seemed that the curve bent on the tang was a little too steep (low at the back). In order to get flat contact on the face of the stock, I had to drop the inletting for the tang quite a bit and then reshape the wrist accordingly. It worked OK, but there is a significant gap at the back of the tang (approx 3/32"). If I had to do it again, I would consider re-bending the tang (but I don't know if it could be done cold or if the tang would have to be heated). I think I would avoid changing the vertical face of the front bearing face of the stock. It needs to remain square to the barrel -if you tip the barrel down it will likely give you trouble in the barrel channel or a gap at the bottom where the barrel should have solid contact with the tang face.

Anyone tried bending one of the Lyman Tangs?

.......jBrent

 

[thehorn]

I've parted together several GPRs and on three separate ocassions I had to bend the breechplug tang to fit the curve of the stock wrist. I cold bent them by placing the tang facing up in a well padded vise, attached the barrel and used it as a lever to put pressure on the tang and bent slowly downward. Be careful to go slow and only a small amount of movement is needed. Check by placing tang in stock inlet and proceed further if needed to match the bend of the wrist/tang inlet mortise.

 

I've had a few problems with my kit due to poor quality control on this gun. If I had it to do over again, I'd probably buy a factory complete rifle and strip it down and refinish the metal and wood.

I think that is a good idea. I put one together for my son a few months ago and when we bought it, they had 3 in stock. We looked at all three before picking one and all three had problems that would be difficult if not impossible to fix into a factory finished product. This leads me to believe that perhaps the problem guns that can't be finished properly at the factory are sold as kits. One had almost an 1/8" gap ahead of the BP heel. I certainly would never order one through the mail unseen. Regarding bending the tang, in order to get it to look half decent you HAVE to bend it. By bending it down you can file out that hunchback that lyman seems to think it needs and bending it should REDUCE any gap at the back of the tang. If a gap is preseant, it is easily closed providing it's not TOO big and a slight gap (a few thou) is desireable, otherwise, a tight fit may cause the wood to chip under recoil.
Here's a comparison between the factory finished (top) and kit (bottom) finished with the tang bent and the hump removed.

Cody

 

Inspect the bottom corners of the barrel channel where the rear corners of the patent breech tang meets the wood. Refer to AZ's drawing, the part I am referring is where the wood meets the right angle below the red arrow. It may be that corners in the wood are rounded rather than square. If they are, the barrel assy. would be forced forward by a tiny amount.