Bedding the Garand is a multi-step process. First, with the dry stock in a vise, you will need to cut the bedding grooves in the top, bottom and inside of the stock. The location of these grooves is found in the M1 Rifle reprint from the NRA. These grooves act as the anchors for the bedding compound and give added support. What I do is to insert the barreled receiver and stripped trigger assembly into the stock, then with a pencil outline the receiver area on the stock both top and bottom and rear and use that line to guide my cutting in the stock with the Dremel tool. Remove the barreled receiver and trigger assembly and lay them aside. Start working with the rear of the stock where the back of the receiver rests. You will make a horseshoe cut about 1/4" deep around the back of the stock around the receiver bearing area, and about 1" up each side around the top. Don't go all the way up each side. You only need about an inch. The cut should be about 1/8" wide.
Then, you will need to cut similar grooves on the top on each side of the receiver bearing area on the stock. On the left side of the stock, you will need to stop the cut just short of the clip release groove, and not cut into that. On the right side, you will go further. You will wind up with the grooves of different lengths on the top of the receiver bearing area on the stock.
Flip the stock over. You will cut similar grooves on the bottom of the receiver bearing area where the trigger group clip cover sits. You will also cut two short grooves at the back of the trigger area where the trigger housing itself sits at the bottom rear of the stock. Just short cuts, nothing too excessive, leaving the trigger channel untouched.
Next, you will need to work into the inletted area of the stock itself. You will be cutting two grooves in the back of the receiver recess area of the stock for the rear receiver lugs, and two in front, for the front lugs. These cuts are diagonal into the wood and do NOT daylight on top or on bottom. You will be leaving a space of about 1/2 inch at the bottom of the rear receiver lugs, and about 1/4 inch in the front. Be particularly careful about the rear grooves, as these are your primary "bedding" grooves. Take plenty of time; make the cuts as accurately as possible, and leave the tolerances at the top and bottom according to the chart in the M1 Rifle schematic. I like to rough up the face of the rear inlet area where the lugs will be contacting at this time as well.
Next, glue the front metal stock ferrule on the front of the stock. You should first take the swivel and completely screw out of the ferrule and coat them both either with release agent or a good paste wax. Lay the swivel aside for the time being. Next, mix a bit of AccuraGlas, or epoxy, and coat the front of the stock. Slide on the ferrule and wipe off any excess epoxy. Then, making sure the screw is well coated with release agent or paste wax, insert the screw and GENTLY tighten until some of the bedding compound squishes out from the ferrule/stock joint. Wipe off the excess again and then make sure the inside of the ferrule is lined up EXACTLY with the bottom of the stock channel, checking it constantly and gently tapping it from side to side with a dowel or nylon hammer to align it correctly. You should also make sure that the ferrule is exactly in the correct horizontal plane with the channel -- do this by placing a straight edge in the barrel channel and looking at the front of the ferrule. Because the sloppy tolerances in the metal to wood fit, it often will be high or low. Tap squarely into place. You will only get this one last chance for this, so don't forget to square it up. Then, set the stock aside overnight to allow the bedding to cure. Then you can back out the screw, insert the swivel and you are back in business.
This is a good time to do a trigger job while you are waiting for the ferrule epoxy to set. The trigger jobs on an M1 Garand (it is exactly the same for the M1A) are not difficult and excellent instructions are found in the M1 Rifle and Baumgardner books. Essentially, it involves polishing the inside of the trigger housing, hammer sides, safety sides and trigger sides with a good India stone and 600 grit wet/dry sandpaper until it is smooth and the bluing is off. You are not trying to remove metal, just polish the stuff. Generally, you do NOT need to worry about polishing the sear or disconnector faces as most used Garands have pretty decent triggers. One area you do need to polish that is not mentioned in the publications is the top of the safety spring. You can pop out the spring off the side post with a flat-headed screwdriver. Look at where the spring rides the safety -- there is a small curved divot on the bottom of the safety on which it rides. You need to polish the top short arm end of the spring until it has no sharp edges (and rolls over easily), and the inside of the curve of the safety, so that the safety engages and disengages smoothly. Use 400 grit wet/dry sandpaper to start, finish with 600 grit. Then clean everything. I also polish the side of the spring as well, where it rides against the safety and other parts, using 600 grit sandpaper. You can pop the spring back on by placing the trigger housing on your bench, laying the spring on the post inside the housing, and then tapping it with a flathead screwdriver inserted through the far access hole. It should not take a great deal of effort. You can also polish the front of the hammer plunger the same way.
Ok, before you actually glue stuff together, assemble the receiver in the stock a few times with the stripped trigger assembly (only the safety, spring, and trigger guard are in the assembly when you glue the rifle). Believe it or not, don't assume you know how to do this. You will be doing it under pressure as you have applied the bedding and sometimes stuff goes wrong when you don't expect it. A little practice here goes a long, long way to alleviating problems later on. You should know exactly how you will be putting on the bedding, inserting the receiver, and inserting the trigger assembly. (Note that you will be leaving off the lower band, gas cylinder, and everything else -- you will be bedding the rifle with only the barreled receiver, and stripped trigger housing with spring, safety and trigger guard.) At this time, you should also place the bedding spacer on the barrel where the lower band was placed and make sure it slides tightly and bottoms into the front ferrule (which should now be glued in place). If it does not, and is too tight, file a bit off each side (make one pass on one side and then the other to keep them even) and keep trying until it fits. If it is too loose, use masking tape on each side (make it even) until it squeezes in the ferrule. Likewise, it should fit snugly on the barrel. If it is too loose, apply masking tape to each side (but NOT to the bottom) until it is tight. You should be able to rotate it around the barrel a bit by hand with some effort. It is critical to keep the bottom of the spacer barrel area in contact with the barrel and the bottom of the spacer in contact with the ferrule. That distance is .75 inches and establishes the pressure point needed on the barrel to make the gun shoot better. Don't add tape to either of those areas, which will increase the .75 distance, adding excess pressure to the barrel when you reassemble.
Next, with modeling clay, fill every single hole in the receiver. Make sure you fill the hole and slot recesses for the clip latch, the pin holes in the receiver, the front bullet guide slots in the front of the front receiver lugs (note you will have epoxy stuck in those in the front lugs if you don't), and the operating rod slot. Also, put a 1/4" bead around the underside inside of the rear receiver (especially where the "lip" of the inside of the receiver rear is located, but making sure that the clay does not extend below the flats of the receiver rear. Next, do the same with the trigger housing. Make sure you use clay on the trigger slot itself. You should also make sure you apply a ball of clay on each side of the housing where the trigger guard pivots -- when you assemble the trigger into the stock, the clay will "push" out of the way. You will also need to put a small wad of clay in the clip release cutout in the stock itself.
Next, you will apply at least two coats of release agent to the whole receiver bottom, receiver lugs and trigger housing. Be liberal with the release agent. If you are used to going sparingly on a bolt gun, don't try this with the M1 as there are many, many places where epoxy can get and lock the receiver into the stock, causing you to break out a chisel and ruining the stock to get it out. Don't skimp. Let me repeat. Don't skimp. The release agent should go roughly 1/2 the way up the sides of the receiver both inside and outside, on the sides of the lugs, front and back, inside, etc. When dry, then use some liquid paste wax on everything in the receiver area where you did not put release agent and for good measure, about 2 inches on the barrel in front of the receiver. A bit of paste wax and release agent is a lot cheaper than a new stock. Let the paste wax dry. Then, as an added assurance, overlap the junction between the paste waxed area and the release agent area with one coat of release agent. Let it dry thoroughly -- at least 1 hour.
You are now ready for the big glue-up.
I like to mix the bedding compound on my bench, using a couple of strips of duct tape on the top of the bench and mixing the bedding compound on top of that. It is easier than mixing in a small jar and you get a better mix. Mix the bedding compound according to the instructions. You will not need as much as you think. You should be able to have sufficient if you use two scoops of the small plastic spoon that is included with the kit. You can always mix more and having excess is not particularly good because you just waste it. I use popsicle sticks to do my mixing.
When thoroughly mixed, glob some carefully on the interior recesses of the stock area. You should try to "press" it into place starting at one end and pressing forward until the entire groove is filled to minimize the potential for gaps and voids. I like to use compound that is NOT dyed for that area. You can mix some brown dye in the compound that you use for the rear, top and bottom area, if you wish. You don't need to use a lot of dye -- just a tiny dip or two with your mixing stick should be sufficient. Mix the dye in thoroughly.
Then, using a scraping and squeezing motion, squeeze the compound in the top and rear slots working from one end to the other to avoid gaps, leaving ample excess outside of the slot. Make sure there is plenty of compound all the way to the bottom of the recessed cut. Using a sharp pointed stick and swirling it in the cut will help achieve that. Leave plenty of excess on top. I like to see a mound of about 1/8th or more above the slots. Turn the rifle stock over, and do the same with the bottom slots and rear trigger slot. Be particularly careful in the rear trigger slot to keep it out of the trigger groove itself.
Now the moment of truth. With the barrel spacer in place and the stock held right side up in a vise, slide the barreled receiver into the stock. Go slow, carefully push straight down and do not pull it out once you start putting it in. You can gently rock it a bit to help the glue to be evenly distributed. When it is fully in the stock, check the barrel spacer to make sure it is in the ferrule. Then, with the rifle supported in the receiver (a rubber band or two helps), flip the rifle over. You will see a lot of the epoxy has been pushed out. VERY carefully, using a few DRY cotton swabs, tease that glue out of the area. Be very careful not to disturb the release agent on the lugs. Pay particular attention to the locking areas of the rear lugs, and the slot into which the trigger assembly will slide. Then, when you have carefully teased out the excess glue (don't worry too much at this point about glue that is squeezed from the sides of the rear lugs except in the area of the locking area), gently lower the trigger assembly into the anchor slot. Then, with a short prayer, lever back the trigger guard until you can insert the U bar clip in the safety hole and around the outside of the trigger guard. The safety should be in the "on" position (to the rear). That will leave the trigger guard holding outside of the lockup by about 1/2" or a bit more.
Next, turn the rifle back right side up. Visually check the alignment of the barreled receiver and the spacer to make sure everything is perfectly aligned and the spacer is sitting on the barrel and the ferrule, that it is straight up and down, and that it is aligned with the center of the bore. Your visual reference will be pretty good here if you are not cockeyed. If it is not centered and aligned, hand maneuver the alignment into place with the stock securely anchored in your padded vise. You may have to "horse" it around a bit, just be careful not to pull out the bedding or you will need to quickly remove the barreled action, clean everything off and start again.
Then, leave it alone. Go to sleep overnight and say your prayers and vow to cease all your evil doings and to take out the garbage for your wife more often.
In the morning, when the epoxy has set up, you will either be happy, or you will be buying a chisel. Turn the rifle over. Remove the U-bar clip. With gentle pressure, pull upwards on the trigger guard. If the trigger assembly comes out, you are almost home free. Next, with the rifle upside down, take a small block of wood or a 1/2 inch dowel, about 6 inches long. With the stock in the vise, and pads under the rifle barrel and receiver, place one end of the wood dowel on the inside of the back of the receiver and with a hammer, start tapping somewhat gently at first, then more firmly. The receiver should begin to drop out. As soon as it moves, you are home free and you can tap more gently until it fully drops out.
If despite your best effort, you cannot get it out, you have a couple more options. Using a CO2 fire extinguisher (I'm not kidding), spray the inside of the receiver until it is coated with white cold frost -- take several good blasts to make sure it is really cold. Then, try your tapping harder this time after about 15 seconds. If it drops out, you are ok. If it doesn't, try putting it in the freezer overnight and try again. If that fails, break out your chisel and plan on buying a new stock.
If it comes out, it is time to cleanup the excess bedding. Use a very sharp chisel or knife and carefully trim the excess bedding compound off of the inside of the receiver inlet, and around the top. Be careful not to nick the bedded area. You are just trying to make it look smooth, and not trying for absolute perfection here.
If you want, at this point you can also redo the entire procedure (new release agent) and bed the sides of the receiver. It is not necessary and you have to have some leeway to allow the receiver to "tip" out of the stock when it is reassembled into a gun. But now is the time to do it if you wish. You should understand, however, that you are not striving to have the sides bedded entirely, as the assembly of the rifle with the uncured side bedding in place will "push" it down to the bottom of the stock. You should not be terribly bothered by that and besides, the receiver will need some area to "tip" out when it is removed anyway. Again, you have to do the same procedures as before but this time, be careful not to add bedding compound to the areas where you have already bedded, unless there are gaps or holes to fill. If you have to fill some gaps, and before you put compound into the stock, scrub out the area with hot water to get rid of any remaining release agent on the existing bedding and let it dry a day or two first before you re-bed.
Once you have done all of that, your rifle is now glass bedded. Wait at least a week for the bedding to fully cure before you take it to the range and test it.
When done, clean all the clay and release agent from the receiver, stock and trigger housing. Reassemble all of the receiver parts, in the same order you took it apart. Follow the diagrams carefully as there are a couple of ways to screw up in the reassembly -- mainly on how you locate the follower and the bullet guides, clip release and follower arm. The diagrams should be followed closely.
For the trigger housing, if you haven't done the trigger job, now is the time to do it following the instructions above. Reassemble the hammer and hammer pin. Then, reassemble the hammer spring housing, pivot arm, and spring. Grease them before putting them in the housing and make sure the housing cut is facing the sideplate of the housing, and not outward. Now the tricky part. With the hammer released, you need to align the trigger/sear assembly hole and the spring housing hole, with the pin hole in the housing. This is NOT easy the first time, but comes easier with practice. I generally hold it all in my right hand, compressing it with my forefinger until I can drop the pin in from the right side, then insert the housing assembly in my padded vise and GENTLY compress the whole hammer spring and trigger/sear assembly with my vise until I can push the pin flush with my finger. The CMP has some excellent photos on how to do this on their website. You will have to experiment on doing this and don't try to rush or force it. It just takes a while and you will be frustrated the first few times you try. But, you should not have to pound in the pin. At the most, a gentle tap or two with a brass hammer should suffice.
You should also coat all the unbedded inside stock surfaces with a good grade of spar varnish or other sealant, to avoid any moisture warpage. I use two coats of spar varnish, but other sealant products or poly work just as well.
When all is reassembled, coat the inside working parts of the trigger housing with a light grease or oil (I like Lubriplate, which holds up to the extreme desert heat), and then you are ready to reassemble the rest of the rifle and go test fire it. Take it to the range and test your bedding job and see what kind of group improvement has resulted. There is more work to do, as you will note below (and probably from your target results). When you are shooting, use a rest on the stock only -- not on the handguards. You are not trying to center the shots, you are only shooting for group. One inch equals 1 MOA at 100 yards. Two inches at 200 yards is 1 MOA, and so on. Load and fire the rounds one at a time, using the single load adaptor or "SLED". Fire successive 5 shot groups to establish your group size. If you are testing ammo, use at least 5 rounds of each load. Otherwise, use good quality ammo, preferably Lake City match ammo for the Garand, or equivalent, if you can get it.