Epoxy for pillar bedding plastic stock?

03 September 2001, 05:10

<gone hunting>

Winchester Black Shadow cheap plastic stock.
Pillars are Naval Bronze with knurled outer surface.
Which Epoxy would bond best to the plastic stock?

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born on a mountian, raised in a cave, hunting and fishing is all i crave!

03 September 2001, 06:11

Mark

Most of them would do fine. However, since you are asking this question I suspect you are seeking the "best" answer. In that case I'd suggest a softer type of epoxy, like the 30 minute "quick set" variety. If it is going into something with flex in it, make sure it doesn't claim to be "machineable" or threadable. Rough the surface with 100 grit sandpaper, and don't be afraid to file some grooves into either surface. And just before you mix up the epoxy wipe the area down with a Q-Tip dipped into plastic pipe primer. My only concern with these softer epoxies is that heat softens them sometimes, but the pillars should be pretty well insulated from that. I wouldn't use it on scope mounts though, for example.

03 September 2001, 10:17

Atkinson

Since you asked the question I,m assuming you have not used much glass bedding material....

Brownell's Gel is what you want...Quick setting epoxy can get you into a world of trouble, if you ain't quick!!!! Brownells steel bed is another option...

You would be wise to bed the whole stock from tang to forend as that stock is a whispy piece of crap and needs stabalizing with a aluminum H bar....then its fine. You gotta get that flex out...

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Ray Atkinson

ray@atkinsonhunting.com
atkinsonhunting.com

03 September 2001, 10:46

<Don G>

I'd try either MarineTex or Brownell's steel bed. Rough up the stock and dig some bell-shaped holes where there's enough meat in the stock. Several here have suggested the ABS pipe primer as sold in Home Depot as a cleaner. I used acetone. Whatever you clean with, make sure it has dried completely before pouring in the bedding.

Don

03 September 2001, 12:31

<gone hunting>

quote:
Originally posted by Atkinson:
Since you asked the question I,m assuming you have not used much glass bedding material....
Brownell's Gel is what you want...Quick setting epoxy can get you into a world of trouble, if you ain't quick!!!! Brownells steel bed is another option...
You would be wise to bed the whole stock from tang to forend as that stock is a whispy piece of crap and needs stabalizing with a aluminum H bar....then its fine. You gotta get that flex out...

i've bedded 10 fiberglass and 6 lamanates but never fooled with one of these cheap plastic stocks. i've always used Marine Tex. but was looking for an epoxy that would better bond to plastic.
i thought about running a tap through the holes to give a mechincal lock.
this winter i'll replace the junk stock with a Boyds JRS stock.

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born on a mountian, raised in a cave, hunting and fishing is all i crave!

03 September 2001, 18:00

Mark

The problem is not the bonding of the epoxy to the stock, the thing that kills it is when you use an epoxy that is noticeably stiffer than the stock, no matter how good the bond it will eventually pull away, hair by hair, due to the differences in flex.

Like Ray says, the best solution is to bed a piece of metal in there, as that not only increases the longevity of the bond but also makes the gun shoot better too, which is the goal of this exercise. If you are doing that, then some hard stuff like marine tex will be OK too. If you are just doing the pillars then as I suggested a more flexible type of epoxy will last longer. Your idea of running a tap through the holes is a good one, or even just an oversize bolt to put some ridges in there.

03 September 2001, 22:11

<Don G>

gone hunting,

On my Browning Composite Stalker, I actually drilled and tapped the stock, drilled out some 7/16 bolts and used those for pillars. I bedded the pillars in with steel bed after cleaning with acetone.

I stiffened the forearm with very small diameter carbon-fiber arrows down each side (slotted the bulkheads and even the bedding flat to allow a continuous run from magazine to forearm tip) steel-bedded the action, then filled the forearm with a microballoon/epoxy mixture. This is available from hobby shops where they cater to the remote-controlled airplane crowd. It saved a couple of ounces, but solid epoxy would probably work as well.

It was a lot of trouble for a .308, but changed it from a two MOA to a .5 MOA average group size. I intended to replace the stock, but never got around to it. (See Atkinson's corollary to Murphy's law.)

I still consider it polishing a turd, however!

Don

[This message has been edited by Don G (edited 09-03-2001).]

03 September 2001, 22:17

<gone hunting>

[QUOTE]Originally posted by Don G:
[B]gone hunting,

I still consider it polishing a turd, however!

i like that! vary well put!

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born on a mountian, raised in a cave, hunting and fishing is all i crave!