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the_ursus
01-29-2010, 08:19 PM
I have a .350 Rem Mag. in Rem 700 with an inexpensive Remington injection molded stock. I'm thinking of epoxy bedding the action and, given the healthy recoil, I believe it would benefit accuracy. I have a large supply of epoxy on hand similar to that of West Systems (marine). I'm familiar with the basics but have had a hard time finding info dealing with injection molded stocks.

My concern is getting a good bond of epoxy to plastic.

jbc
01-29-2010, 08:37 PM
roughing up with coarse sandpaper and scoring a bit with a carbide scribe then cleaning with denatured alcohol worked for me. Also i have heard of people scribing out undercut pockets in the plastic(deeper at bottom than top) to get the bedding compound to mechanically grab the plastic

the_ursus
01-29-2010, 08:59 PM
Thanks jbc, what you described is what I was thinking of doing.

PS
Also, I realize this stock is not ideal for such a "kicker" but thought I'd give it a try since I have it.

Doc Highwall
01-29-2010, 10:06 PM
I am not familiar with West Systems (marine). What is the shrinkage of the material. I use Accura Glass or Bisonite when I do mine. The labor to do the job with the wrong material vs. the right material is the same. Me not being familiar with that material, I would find out before starting the job. Are you going to use pillars also. I have heard of people using auto body filler (bondo) and claiming it was good until after so many shots that it cracked under recoil.

DLCTEX
01-29-2010, 10:17 PM
Auto body filler does not stand up to impact or pressure very well. I think the marine epoxy will do much better. As stated scratch it up good to give it someplace to bite. Liquid steel epoxy is reputedly good bedding agent.
I plan to bed a metal rail in the tupperware stock of my new Stevens 22-250 using epoxy and will bed the action when I do.

10 ga
01-29-2010, 10:26 PM
I have used West in marine applications but not to bed stocks. Rough the plastic with sandpaper, dremel tool or emery board etc... The West epoxy should stick good. I use filler in my epoxy to thicken. I would stay away from stuff like microballoons and use the chopped kevlar. That should make it plenty strong.

That deer head stew looks yummy. Makes me hungry.
10 ga

Doc Highwall
01-29-2010, 10:31 PM
DLCTEX, I saw some place where they were bedding a Savage tupperware stock for the ML10-II stock and to stiffen the forend they placed steel rods in the epoxy. One person even placed a steel tube in the forend for the ram rod to go through it.

Gunfixer
01-29-2010, 10:55 PM
My method is to take a dremel tool with a bit that looks like a dovetail cutter but does not cut on the face and undercutting the area to bed around the perimiter. then in the middle (forward of the recoil lug area) on the bottom, drill 2 pilot holes (not all the way through of course) and screw in 2 self tap sheet metal screws with one drop of 5 min epoxy on each. cut the heads off the screws low enough to not come through the bedding compound. If the stock has a large opening (i.e. Ram-line) dam up with clay or play dough to stop forward progress, clean with alcohol or similar and follow normal procedure. This has worked for me on Ram-Line, Remington, Ruger, The one for the Mosin/Nagant that I cant remember at the moment, and others.
Hope it helps
pm me if more is needed

docone31
01-29-2010, 11:30 PM
West Systems is a pretty substantial epoxy.
You will need micro balloons. You will need to stiffen the mix. You will also have to rough up the area to be bedded without making it weak.
Make the typical clay dams, put in the epoxy/microballoon mix, torque the action to where it is to operate.
Use the typical mold release(s and tape where the epoxy is not wanted.
Have a ball.
Make sure, there are no positive angles in the bedding! You do want to remove the action.
I have fired a stuck action loose. The mold release, released under the vibration of firing.
I was lucky.
I thought the stock and action had become a permanent item.
Whoopsie.

dualsport
01-30-2010, 03:29 AM
To be sure I'm getting this right, I can pillar bed and glass bed a injection molded stock? Between the two it should be pretty darn solid. Then free float the barrel? I have a Weatherby Vanguard short action that needs help, maybe bedding and some trigger work. I think it wants to be a sub MOA, not quite there. The factory stock is a cheapie.

l-weinrich
01-30-2010, 07:59 AM
I glass bedded a ruger lightweight RL77 in 308 and got some improvement but not as good as I wanted until I got the bright idea of dampening the barrel vibration by using black RTV between the fore end tip and the barrel. Shoots around 3 shots into an inch now with "J".
Don't know if the stock will come back off though.

DLCTEX
01-30-2010, 01:32 PM
I found there is enough clearance, by taking a small amount off the ribs inside the barrel channel, for a 1/4 x 1 steel bar. I plan to fill the cavities under the barrel and just cover the bar with epoxy. The gun is light enough that the extra weight may be good. I'll have to see what effect it has on balance.

deltaenterprizes
01-30-2010, 01:44 PM
Marine-Tex grey is a good epoxy to use for bedding and is sold by Brownells.

Doc Highwall
01-30-2010, 03:09 PM
I bedded my uncles Remington model 7 in 7mm-08 with the pencil barrel about 20 years ago, it would always throw the first shot 6"-8" out at 200 yards. I decided that with the wood stock that I would bed the entire barrel channel when doing it. I figured a worst case scenario would be that I would remove some of the bedding compound if it did not shoot and the wood be sealed. Long story short the rifle shoots 10 shots into less then 2" at 200 yards with no fliers.

Charlie Sometimes
01-30-2010, 03:27 PM
What about using two part epoxies like Loctite Professional Extra Time (sets in 60 min. instead of 5 minutes) stuff?
Stiffen it up with fiberglass mat clippings, and have the extra time to get everything right- mix laquer based model paint in for coloring, too, if you want to match to stock.
Has anybody used these products?
What Brownells sells has got to be nearly the same as the other products, wouldn't they?

Herb in Pa
01-30-2010, 07:45 PM
Marine-Tex grey is a good epoxy to use for bedding and is sold by Brownells.

Works great on the Remington 700 ADL synthetic stocks.......

largom
01-30-2010, 08:44 PM
Making undercuts as Gunfixer described is the way to go. I always use an epoxy containing steel particles such as Devcon or Brownells Steel Bed for the recoil lug area and around the pillars.

Larry

Houndog
01-30-2010, 09:20 PM
I've used Acra glass, Bisonite, Marine tex, and several other supposed to be super bedding compounds and finally settled on Devcon. IT's all I ever use anymore whether it's a straight bedding job, a pillar bedding job or a glue in for a Benchrest rifle.

Charlie Sometimes
01-30-2010, 10:07 PM
This is interesting.

I've got a new take-off Winchester LA Heavy Barrel factory synthetic stock that I am going to put on an early Post 64 rifle. It will need bedded, and additional filler here and there, so I am considering using something besides Acrglass Gel- not enough product for the price either, IMHO.

On this stock, where the recoil lug is and back at the last action screw, they had shot a little of the injection mold plastic on those two spots and then set the barreled action in it, securing it like a bedded action. These pieces came out when I put my action in and removed it for check fit, so I have more room to work now. I'm gonna pillar bed it, too.

What difference does the steel particles make? I've never used filler except for color or reinforcing. There isn't any interlocking characteristics with that.

robroy
01-31-2010, 11:57 AM
Epoxies don't actually bond to polypropylene or polyethylene. I think these are what is used in most injection moulded stocks. Success when filling these depends on interference between the epoxy and the tupperware. Undercutting or screws work very well to give the bedding something to grab. I think roughing the surface may give some strength to the "bond" but not enough to do the job permanently.

the_ursus
02-01-2010, 01:36 PM
So the epoxy that I was refering to is actually used for laminated bows (Smooth-On). It is strong, flexible and doesn't drip so I think it would be good to try. I'll follow up with the results when I know more.

largom
02-01-2010, 10:07 PM
So the epoxy that I was refering to is actually used for laminated bows (Smooth-On). It is strong, flexible and doesn't drip so I think it would be good to try. I'll follow up with the results when I know more.


You do not want anything "flexible" behind the recoil lug.


Charlie Sometimes, The steel particles in epoxy's like Devcon and Steel Bed are to make the cured material as hard as steel. You can drill and tap some of them.

Larry

Charlie Sometimes
02-01-2010, 10:54 PM
Since the epoxy isnn't steel, then no matter how much you put in, it can't be as hard as steel. You can drill and tap just about anything that is solid enough, but I can't see getting enough steel particles in to the epoxy to make any difference. There must be enough epoxy to effectively bond the materials together or it would compromise the weld.
Steel particles would be too small to reinforce anything- now it would stiffen the material to make it thicker to stay in place and not run away, IMHO.