Bedding; before, after and lessons learned

[devildoc]

So I finally decided to break down and learn how to bed a rifle. After doing some research over a month or so, I ordered some Dev-Con Steel putty and some brownells release agent. Went down to wally-world and got some modeling clay and set upon the task of trying to bed my A-Bolt without glueing anything together that didn't belong glued together. After pulling the stock off, I noticed a couple things. First, the recoil lug on the factory stock seemed to be bedded by what seemed to be a teaspoon of Elmer's glue, since I could literally peel it off with my pocket knife. Then there was the fact that I would have to fill the dead-spaces in the tupperware stock with something before bedding unless I wanted use the whole pound of Dev-Con I had. Lastly, bedding the tang area of the A-bolt seemed a bit to tricky for me right now, just not enough room between the action bolt and the trigger group recess for me to try and bed without getting epoxy into the trigger group and such.

So I decided to first bed the barrel channel to be able to index the action area properly off the tang and barrel channel. So I put two layers of masking tape on the barrel, filled the dead-spaces with rectangles of styrofoam, masked of the stock and hosed the barreled action down with release agent. Mixed up some putty and layed it down in the barrel channel and then put the barreled action in and put in the action screws just snug. I realized at this point that I should have mixed up a little more epoxy and put it in a little thicker, as I only had epoxy sqeezing out in about a 3-4" section of the barrel channel. But oh well, It'll be enough to index the barrel off, and I can finish off the rest when I bed the action.
Couple days later I broke the barreled action free with a couple smacks with a rubber mallet and relieved the recoil lug and action areas with the dremel. Mixed up some putty, hosed down the action area and action screws, checked my modeling clay, then went ahead and poured the putty in the action, recoil lug and parts of the barrel channel that needed more putty (had the action screws taped up in their screw holes). Carefully screwed the action in to keep putty out of the threads of the action screws, and again just snugged the action screws. This time it looked like I had enough putty and had epoxy sqeezing out everywhere it needed to. Broke the action screws loose 4hrs later and everything pulled out OK the next day.
After cleaning everything up and putting it back together everything seemed fine except that it appeared that two layers of masking tape had not been enough to free-float the barrel, I couldn't get a thin piece of paper in there, let alone a dollar bill. So after thinking about it a couple days, I decided I would just have to sand it out a bit untill I got enough relief. Whew! let me tell you, you can't take that dev-con out with hand sanding. I finally had to break out the sanding wheel on the dremel, I had been through a whole sheet of 100grit and hand sanded for a full hour and hadn't made much progress. So, here's the finished product, It ain't pretty but I hope it will be functional. Hopefully my next try will go alot smoother and come out looking alot better.

 

[Wild_Bill]

Bedding

Hi Devil.

You don't need to bed the barrel channel you could have made a dam from the modeling clay. If possible always remove the trigger and boltstop. I always tape 3 layers off 100mile an hour tape fer the barrel tennon clearence.

How thick ic your bedding it should be at least .100" thick. also did you tape under the recoil lug? this is verry important as if you don't you can get vertical groups you want to tape 2 or 3 layers off 100mile an hour tape on the bottom of the recoil lug with the top layer coming up the sides only around 1/4".

You should also drill some small holes under the area you wish to bed and open the gap behind the recoil lug and open around ALL areas that will be bedded to allow enough strength so the bedding won't flake out.

You could re skim bed the barrel channel take the bedding down and use the tape.

I hate to say it I would grind it out and call your first attempt practice.

Also tape the front off the barrel at the front of the barrel channel with tape to centre the barrel and just use the screws to locate the action don't screw them down or you could place stress on the action and end up with the bedding sinking. I usr a piece of tape carefully over the front off the action just to hold the action down with slight tension others use surgical tubing.

I hope this helps.

Cheers Bill
Australia

 

[devildoc]

Hi Devil.

You don't need to bed the barrel channel you could have made a dam from the modeling clay. If possible always remove the trigger and boltstop. I always tape 3 layers off 100mile an hour tape fer the barrel tennon clearence.

How thick ic your bedding it should be at least .100" thick. also did you tape under the recoil lug? this is verry important as if you don't you can get vertical groups you want to tape 2 or 3 layers off 100mile an hour tape on the bottom of the recoil lug with the top layer coming up the sides only around 1/4".

You should also drill some small holes under the area you wish to bed and open the gap behind the recoil lug and open around ALL areas that will be bedded to allow enough strength so the bedding won't flake out.

You could re skim bed the barrel channel take the bedding down and use the tape.

I hate to say it I would grind it out and call your first attempt practice.

Also tape the front off the barrel at the front of the barrel channel with tape to centre the barrel and just use the screws to locate the action don't screw them down or you could place stress on the action and end up with the bedding sinking. I usr a piece of tape carefully over the front off the action just to hold the action down with slight tension others use surgical tubing.

I hope this helps.

Cheers Bill
Australia

Well, I bedded the barrel channel because the stock had too much flex, and would contact the barrel when I used the Bipod, so I bedded it in the hopes that it would stiffen the forend a bit, and it appears that it has done so.

I did tape the bottom and sides of the recoil lug with one layer of masking tape, didn't mention that, sorry.

I did relieve the recoil lug recess and action areas prior to bedding, bedding should be at least .2" thick in all areas of the action and recoil lug, might be thinner in the bottom of the barrel channel, but I'm not particularly worried about that.

As for the drilling holes, the stock was pretty rough from the end mill on the dremel so I should get good adhesion, I guess I'll find out after I put some rounds through it.

I'll shoot her and see what she does, if she shoots like crap I may try, try again. If she shoots good, I may grind the barrel channel out further and skim bed it to make it look pretty. I'll update you after I take it to the range. Thanks for the advice though.

 

[Wild_Bill]

Sounds OK

That sounds Ok. You have done most steps you may have benifited with more tape under the lug but time will tell. With the barrel channel yes you will stiffen it and no one can see the finish underbthe barrel. If you want to finish it again deemel it down a bit and just use a lot more tape and you should be good to go. With the plastic stocks most ar verry dense so they getvaway without pillars.

Good Luck I hope it shoots I was not trying to say you did it wrong as I don't know the ectbsteps you took just some pointers and if it was rough and the epoxy is thick enough you will be good to go. It has to be better than factory I don't know why they bother.

Cheers Bill
Australia

 

[devildoc]

No offense taken, I appreciate the advice, guess I didn't really explain everything I did very well.

I totally agree with you on the factory stock thing, after pulling the thing apart I can't imagine how I ever managed to get a 1MOA group out of the thing.

I think next time I'll do some things differently, I by no means think I did a "professional" job this time around. But, I didn't really expect to, and as you said, I was pretty sure I couldn't make things any worse by trying, unless I glued stuff together that didn't belong that way. After I get some more experience I may try to bed the tang area.

I'm pretty sure that the action is relatively stress free, I didn't tighten the action bolts down during bedding, just hand snug. Next time I may make some stockmaker's bolts and just tape things down with electrical tape. I also plan to spend alot more time masking things down. I had to spend quite a bit of time scraping epoxy off the top edge of the barrel channel this time, I hit it with release agent, but It would have been a whole lot faster if I would have masked it and cut the edge with an x-acto knife. I will definately use at least 3 or 4 layers of tape on the barrel channel if I ever have to bed another barrel channel. And finally, I'll always make and put a good deal more epoxy in than I think I need, It's much easier to throw away a little epoxy than have to try and fill all the little voids you leave when you don't use enough.

Why would more tape be needed under the lug? I would expect that the lug wouldn't heat up very much or very fast, as long as it's not making contact I would think it would be fine.

 

[Wild_Bill]

Recoil lug and tang

Hi th reason with more tape under the lug is incase the bedding sinks a little over time or a foren object gets under the lug you won't have it touching.

You say the tang is not bedded it should be done at the same time as the front off the action because devcon is fairly solid you can't make the action pull down at one end onto a solid surface while allowing the other end to find the exact level.

Have a shot off it and then I would remove your trigger saaembly a d re skim bed the front off the action and the tang area. I would probably bo the barrel chanel first so you can space it up off the channel with tape so the barrel sits in the channel at the tip off the stock and the
n place in the bedding compound you only need your action screws just start their threds and slowly settle the action to its correct hight then carefully tape down with 1 layer off thick 2" tape and use the back off a steel rule to slowly remove the excess compound. As for the overflow into the trigger and. mag cutouts you can use your dremel to machine it out when dry you realy don't require pluging it all up with modeling clay.

Cheers Bill
Australia

 

[dirtball]

Devildoc
I found this article on 6mmbr.com some time ago. You might find it worth reading, I did.
Dave

Stress-Free Pillar Bedding

 

[devildoc]

I actually read that article prior to bedding this stock. And decided to do the things the way I did based on alot of what he was saying. Problem was that I didn't really have enough room to mess with bedding the tang on the A-bolt and that I needed to stiffen the forend enough to accomadate shooting from a bipod. So I bedded the barrel channel first in an attempt to index the barrel in the channel (as well as reinforce the forend), as he did by using electrical tape and then proceeded with bedding the action. The barrel channel bedding ended up looking kinda ugly on mine due to having to remove bedding to get enough clearance. That could have been prevented by using an extra layer or two of tape on the barrel, also I'm not sure if the forend of the stock was so flimsy that it flexed out from the barrel when bedding compound was in the channel, so that when I removed the tape the forend flexed back, making contact with the barrel. I still haven't shot it yet to see if any improvement has been made, I expect that it will improve, simply from better contact with the recoil lug and action. I doubt that I created any more stress on the action than was present before bedding. But only some good old fashioned trigger pulling will tell the tale. I'll let you guys know how it works maybe this weekend.

 

[devildoc]

well, I took her out to the range today and tried some 250gr partitions pushed by 72.5 grains of RL19. Turned out to be a shotgun pattern (~6" at 200), so to make sure I hadn't messed anything up by bedding I shot a group of an old load I had worked up that shot 1-1.5MOA with the 200gr b-tips and sure enough they shot right at 1.25MOA even though the wind had kicked up quite a bit (10-20mph). So I'm sure I didn't hurt anything, we'll see if I helped anything after I do some more shootin' with her.