Hello,

I am in the process of building a gun stock for rem700. Before anyone asks why I'm building one instead of buying one - my main hobby is woodworking and I have all the tools I need, so I am not investing any money beyond the raw material. And, I love designing and building stuff. I have built a couple of gun stocks before but this time I am trying something different.

I want to build a stock out of wood/laminated plywood. I was thinking removing all material under the receiver and filling it back with a mix of fiberglass tape soaked in epoxy resin to reinforce the sides, then filling the rest with epoxy resin mixed with fumed silica and short strand glass fibers. The point of this would be to remove any possible wood movement under the receiver but still maintain the outside looks of wood/plywood.

I was very optimistic about this until I realized that the only thing that can make this entire idea fail is heat, so I started looking into heat resistance of epoxy resin and it's not much at all - most websites report 120-200 degree Fahrenheit for Tg, which is the point at which the epoxy starts turning rubbery. Upon further research, I found why manufacturers like McMillan cure their stocks in machines under higher temperature - because resin cured at high temperature has much higher heat resistance than when cured at room temperature.

Nevertheless, I have come across posts online on various forums how guys have made their own molds and made a stock using readily available epoxies and fiberglass cloths such as totalboat, west systems, etc. Also, just about every bedding compound is epoxy based, yet I have never of a ruined bedding job because someone got the receiver a bit too warm from continuous shooting.

So here is my question: does anyone around here have experience with epoxies being exposed to too much heat?

Thanks

Dan

The resin/epoxy you pick will completely determine the resistance to temperature and there are several options that will work way hotter than you will ever get a receiver.  Cure time and temp resistance are sometimes linked but not always.  There are definitely epoxies that can handle 300+ degrees no problem.

Unfortunately I've been out of the composites game long enough I don't know where you'd get or what you'd get but I'd bet if you googled around for epoxy suppliers and started asking questions they could point you in the right direction.  You're looking for moderate strength, minimal shrink, and 175-250 degrees F max operating temp.


OR, glue in an aluminum mini-chassis.

I have completely recast transfer ports on 2-cycle race engines that run very hot, with Marine-Tex epoxy, and that shit never softened.


There, fixed

I want to avoid the aluminum bedding block because I would bed on top of it anyway.

As far as epoxies.... anytime I try to google anything I keep getting the same results.