Home Forums Hunting & Shooting Gunsmithing Fitting a cupped buttplate

I've been working on a 1903 Springfield NRA Sporter restoration project and have a question about fitting the buttplate. The buttplate is a cupped design which creates a bit of a reach for the screws to make before they connect with the wood. This, coupled with the plate only making contact with the sock along the its rim, seems not like the most stable platform for mounting it all up. Anyone know how Springfield Armory fit these plates to the NRA Sporter stocks as they certainly made enough of these rifles and I haven't read or heard of any issues with the buttplates coming loose or detached. Thanks.

Fitting dished butt plates is something I do all the time. The trick for ones like you are working with is to make sure you are letting straight with no twist, and just go slow and take it straight in. As the sole of the butt tightens so does the tang on top (called the "return" in the old days)

Some butts are best inletted forward and then down and others need to go down and then forward..
Here are some examples of those that need to go down and then in.
OLYMPUS DIGITAL CAMERA by .com/photos/156296479N08/]Steve Zihn, on [bleep]

100_1479 by .com/photos/156296479N08/]Steve Zihn, on [bleep]

100_1198 by .com/photos/156296479N08/]Steve Zihn, on [bleep]

here are some examples of the kind that need to go forward and then down.
000_0191 by .com/photos/156296479N08/]Steve Zihn, on [bleep]

97 Jaeger comb by .com/photos/156296479N08/]Steve Zihn, on [bleep]

aag-443_3 by .com/photos/156296479N08/]Steve Zihn, on [bleep]

2 tools that will help you a LOT are a curved gouge that matches the radius of the tang you are working with (or slightly smaller, as you can cut a large radius with a smaller sweep, but not the other way around) and a 1/2 round file.

Heat the file medium red and bend it a bit so the round parts is bellied out. Quench in cold salt water. If you quench from medium red the hardness is not effected on the files teeth and it cuts very well. By having it be bellied out you can inlet the radius with it like a scraper, but the end grain of the stock wood doesn't interfere with a file in ways it can with scrapers. The file is WAY more forgiving.

Remember to keep the butt plate perpendicular to the butt. Don't allow the tang to go up-hill, down hill and let the sole of the plate go in twisted to either side.

Hope this helps. Good luck.

Wow, thanks and nice looking stuff you have there! I never really thought of it before but the top tang of a classic "Model 70" type of buttplate must have been made that way to help stabilize it to the stock.

Jeff, I never fitted a cupped NRA Sporter butt plate, but I know what it looks like. While the above examples don't address your particular need, the thought process is much the same I should think. I would first acquire a pair of longer screws to make the reach into the wood until you get close enough to switch back to the standard screws. Work slow using plenty of inletting black (or whatever you choose to use to mark the high spots). You will do more scraping than paring, but regardless keep your tools razor sharp. The edges of the wood behind the inset that the cup captures will need to be slightly radiused to allow the bottom of the plate to contact the wood solidly. Rifles assembled at the Armory didn't receive much hand fitting- their stock turning "lathes" were pretty accurate. NRA Sporters I've viewed had their cupped butt plates fitted about as closely as what one would expect to see on standard grade commercial rifle butt plates of the era, close but not perfect. Be sure to let the surface of the wood stand about 1/32" proud of the plate.

I sometimes wonder if they didn't grind/file on the edges of the cupped butt plates to get a decent fit on the machined butt stocks rather than fiddle with the wood to get a perfect fit.

So is it just the shear force of the screws that hold it in place. I thought about adding a small ledge to the base of the stock that would protrude into the cup by about a quarter of an inch or so to help keep the buttplate from being knocked sideways and out of place. But if this isn't necessary then I'm not one for overcomplicating things. Thanks

Well yes, the screws do hold it, but the fit of the wood into the hollow of the butt also gives it a lot of strength.

The "modern fix" is to get the edges tight and then fill the void with Glass Bedding compound with steel powder mixed in, or a lot of fiberglass flok.

The old way is the one that was used for centuries and it's the best one to show off your skills, but a filler of glass bedding is actually stronger then the wood itself.

In either case the edges should fit tight, and you should have at least 3/16 contact of wood to metal at all points on the perimeter of the metal to wood.

Jeff, I somehow get the impression you're not picturing the butt plate fitting down over the wood, with the inside bottom of it landing solidly onto the end grain of the stock. Two areas requiring attention: the vertical curvature of the butt plate, and the inletting for the sides of the "cup" (referencing the need to allow a bit of proudness of the wood ahead of the cup).

I may not be getting it. The butt of the stock is dead flat as too is the mating surface of the plate. My concern has to do with the parts that actually fit together and how strong of a fit that contact patch will make. A I see it, the contact patch is defined only by the rim of the buttplate where it touches the stock. So its like a coffee cup sitting upside down on a table top. The only thing that comes into contact with the table top is the rim of the cup. And the only thing that holds the plate in place is the amount of pressure the screws put against the assembly. I'm not the sharpest tool hanging in the barn so there may be some stuff I'm not fully understanding.

Text me a pic of the stock as it exists now, and we can continue sussing it out privately and post a final solution for those whackj, er, aficionados, that may be confronted by the same conundrum.

Yes that is one way of doing it, but having the hollow under the plate means that if a blow collapses the plate the edges will bend up and away from the wood. Your coup upside-down on the table is a good way to illustrate the point.
If you put that cup upside-down on a thick sheet of soft clay and pushed it down until the clay filled the cup, and paired away all the clay on the topside, that would make for a stronger fit. You can fully inlet the wood until it does that, or as I said above, you could fill the cavity with a strong substance like Accra-Glas + steel powder or fiberglass flok.

I like the old fashioned way because I am "old". But the new way (with a filler) is actually a bit stronger.

Yeah - that makes sense. Thanks

I'll send you some pictures after work tonight - thanks

As long as the epoxy isn't just mounded up on the end grain of the wood which makes for a poor bond. A shallow dish in the end grain would give the sides of the epoxy fill some long grain for it to bond to.

Good analogy about pressing the coffee cup into a block of modeling clay to get a visual of how it's supposed to fit.

One of the things I want to do is stay true to how these things were built as I'm working with an original NRA Sporter receiver, stock and other parts. So while my final assembly may not be historical to what the arsenal actually built, short of the barrel it will be made up of recovered NRA Sporter parts that are of original manufacture (I've been scrounging for years). I'm not sure if I should call it a restoration, reproduction or a "controlled bubba" project.

There's no reason you can't have the butt of the stock domed to fit the cup in the butt plate. When carving a stock it is important to plan ahead and think of the type of butt plate you want to install so the stock can be carved accordingly.

Not an export at all but one thing I learned by doing wrong is to not pre-drill the screw holes, wait till the plate bottoms out and you get close to 100% contact. I fitted a Niedner style butt and had good contact but it was due to the screw tension springing the plate in place. When I glass bedded it the epoxy in the screw holes acted like a lubricant and the plate sprung out of being a perfect fit. If I had drilled after fitting the plate would not have had any tension on it. If you need screws for alingment us a smaller screw then re-drill for the finish screws when ready.

The off set scrapers and some some small chip carving chisels work well for inletting. Get some Prussian blue or lamp black for this as it is more precise than lipstick or smoking the butt plate. It is also easier to round the face of the butt stock before you start so you are removing less wood with the scrapers. There is a Brownells video on this and one stock maker has photos of each step. Stephen Dodd Hughs has many helpful photos some of which are on his web site.

This is one of those type projects that if it is not going well stop and take a break or wait till you can concentrate on it more fully. The pros can do this in a couple of hours me maybe a week.

Spotting dye to fit. No easy way.

Here I thought I was doing good fitting a Sunny Hill bottom metal into a M70 stock. The craftsmanship in the pictures above is absolutely fantastic. I’ve got a bunch of synthetic stocks but I’m really starting to go the other way in my preference.

Sorry for the derail. Hope the OP can put up some pics too.