What is the best way to attach a horn grip cap to a pistol grip?

The Ones I have made for British rifles are attached with an engraved screw. A good epoxy should work fine as well. I always use pins or a tenon for fore end tips but not on grip caps. Hope this helps.
Steve

Yes, that is very helpful. I was planning to just use epoxy, but then all the photos I could find online were screwed in like you suggested. I am replacing the plastic cap on an ithaca 200e. I might go with the epoxy to get a clean, simple look

FWIW the Parker grip caps have 2 small studs in the wood to prevent rotation. Not really necessary but they are there. It may make gluing easier while the epoxy sets.

What mark says is worth consideration. One pin will do, and you want to install it first. With it in place, the screw is easy to locate.

Unless you are sure you want it to be there forever, I tend to use contact cement.

Thus far, all I've done is begin shaping and re-attach with the same screw that came with the gun. I'm having a little trouble getting the wood perfectly flat, but the cap doesn't spin even just with the screw.

Do you all think glue or a pin is necessary or just if I run into trouble with it?

A single screw is fine but it would be better if it had a hidden peg to help prevent turning .

Gluing is fine but permanent , but will that matter , how often will you want to take it off ? Glue such as an epoxy will also fill any small gaps quite nicely .

I have done both so have no preference other than to say IMHO an engraved screw always looks better even if only for decoration .

I intend to sell this gun when I'm finished with it, so epoxy would probably be fine. It would certainly make that tiny edge gap less of an issue.

In intend to clean up the factory screw and use it. The engraving isn't outstanding but it's nice enough

There is an easy way to finish the perfect fitting to the grip. Using a strip of emery cloth of the appropriate grit, and with the buttstock held in a vise at the needed angle, place the emery between the grip cap and the wood with the cutting side toward the wood. Holding firm pressure on the grip cap with one hand, and taking care to hold it in place, slowly pull the emery strip out from between the grip and the cap laterally, trying as best as you can not to pull downward toward the floor because it will round off the edge of the wood. If anything, pulling it slightly upward against the outer edge of the cap. That won't hurt the cap's edge because the emery strip isn't cutting on that side. I prefer to hold the grip cap down with my left thumb and let the emery strip drag across my left hand to prevents it "dragging" on the edge of the wood going in, but watch it carefully.

This method cuts away the high spots. It won't take long before you have a perfect fit. I learned to do this on buttplates and it works just as well for grip caps. This method is only useful for grip caps with no "pegs".

SRH

Thanks Stan. I have been trying to use paper wrapped around a file, but I have a tiny high spot at the front and back despite trying very hard not to put pressure laterally. You can see the gap in the picture.

The good thing is that the center is still relatively hollow so it shouldn't be too hard to remove a little more at the edge

I'm not planning to leave it so thick, but I haven't decided what final shape I'm going for.

Although the posted question had to do with attaching the cap, does anyone have suggestions on how to put a cove on the edge? Router? Gouge and file?

This horn grip cap was imported from Germany, purchased from Brownells and mounted on a custom Mauser I built and dated 1976. The unfinished wooden one I made about 20 years ago just to see if I could do it.
I Never attach Anything permanently to a gunstock. Use a screw, with a peg if you don't want it to turn. This is especially important if you are going to dispose of a gun so the next guy to get it doesn't have to figure out if the previous bonehead glued it on. Epoxied recoil pads are an abomination!
(My screw head embellishment left something to be desired 44 years ago~)

I've got a thin piece left that I'm going to practice on. My idea is to sand the edge over at a 45 on the belt grinder. Then I'm going to try to file a cove all the way around. I'm trying to decide whether to checker or carve something on the flat. Will depend on how easy it is to work with edge tools

Thanks for the pictures Stephen. I wonder if the grooves in the first cap were made with a triangular file. Looks great.

If your cove isn't working out how you would hope, it's possible to make a file guide. Hardened steel is somewhat better, but basically you make homemade washers bigger than your grip cap. With various cobbled up spacers, depth limiting oval and or donuts you sandwich the cap material and center up where you want the cove under a file width slot. Line it up with a small bolt through center and maybe thin two sided tape in spots if needed and steady it in a vise.

I don't have the experience and practice to freehand a decent small cove like this, so it's been worth the set up time and effort to make this type of file guide for me and the results are crisp. It wouldn't bother me to consider a bearing guided router bit edge in a table, but my suspicion would be to use low rpms and nibble. What ever method used, the cove shape does not have to be limited to a quarter round, and for the gun in the pictures, I'd think a subtle dome shaped cap with or maybe better without flutes would have a good look. Only thoughts, because freehand filing or even getting a good starter bevel on the edge might be frustrating. Best of luck.

Here's an update on the horn grip cap:
I decided to go with grinding an angle at 45 degrees followed by rasp, file, and sandpaper to make the cove. You can see the start of the file work in this photo.




Here's the current product. I actually started to checker the flat surface but decided it didn't look great (likely because it was my first attempt at checkering), so I sanded it flat.



I also had to make a new forend tip, which was my first attempt at inlay. This project is providing plenty of stock work experience so far.

Looking good Woodreaux~~ if you keep close to your layout lines and are careful with the tools I find you can do remarkable work free hand. I would recommend getting a Jerry Fisher medium cap for a template. I find it has the best oval shape and the best dimensions of any grip cap I'm aware of. Maybe your oval was made to fit an existing stock but Fisher's oval also makes a more pleasing grip, IMO.
I could send you a tracing if you would like?

BTW: I only use horn for restoration. I prefer ebony for new work. It has more seasonal variation that walnut, but less than horn and I've had worms invade my powder horns. I don't have clue where they came from but it completely unhinged me when I realized it happened in my workshop!!!

Nice job on filling the entry pipe inlet on the forearm as well.

All the grooves and shaping on my practice cap were done with a three-cornered file.

Here is a close-up of a Fisher medium cap with a drill guide to ensure a straight hole. A reallynicely proportioned oval.

Another Fisher cap used on a Britte sidelock. I milled .100" of the top flattening the dome and making it thinner for double gun usage.

Fisher cap scan emailed Woodreaux.
I doubt if the scan comes out actual size? I'd drop the tracing in the mail if you send an address by email.

Thanks for the scan. If you send me a measurement of the length, I can easily scale it to size I think. But many thanks for the offer of mailing. If the digital attempts don't work, I may take you up on the offer.

Edit:. Just saw that you included the measurements. I'll let you know if I can't make it work correctly