[phaed_jb]

very nice work sir. especially like the photos and the opportunity to hear responses and added insight from the 'old timers'. GI2

voting here to make this a sticky.

 

[Ezekiel]

This is great. Lets make this one a sticky if we can.

 

[jkh62]

A side by side of what Devcon covers........

Factory inlet / area to fill~

Mudded~

Looks different now~

 

[jkh62]

Some tooling arrived so back on topic~

I was held up by needing some stainless steel screws and a new 1/4-28 tap that arrived. I have the infamous cold that is floating around so not really feeling gung ho but sitting around drives me more nuts....


Since I am taking a slight detour from completing the bedding ( I needed to remove the action to layout the rear lug position) and machine the correct hole and counter-bore in the stock I will complete these then finish my bedding.

I like stainless steel hardware. Its virtually maintenance free and you really do not need to do much for it or to it. A note about stainless steels~ If a magnet sticks to it, it can stain or rust becasue it contains iron. 300 series stainless steels are non-magnetic, will not rust and will likely outlive any owner. Gun series stainless like 17-4 can be heat treated for additional strength at the trade off of corrosion resistance.

My 1/4-28 socket head cap screws are 300 series and non-magnetic. I also needed a new tap. I prefer OSG / Greenfield taps. Use good tooling for good results.

Now that I have the screws that will anchor my rear lug I can machine a pillar / bushing for it that mounts in the stock area under the trigger group.

The Bushing / Pillar machine~

And with the magic of time you get a new stainless steel bushing / pillar-

Now that I have a bushing / pillar and screw in hand I can machine the stock.

I set up my stock in my milling machine and I indicated it in ( aligned ) using the factory McMillan inletting cuts. I am trusting them that the factory cuts are parallel to their rear lug pocket. I used a dial indicator and indicated off of the flats so they are square and parallel. I kept the bedding tape on my stock and used paper between the vise jaws to protect the stock finish. Once I got it positioned I then used an edge finder or "wiggler" if you are a toolmaker type to find the center line of the slot and set that as zero on my digital read out. Positioning the bushing the other way I eyeballed it closer to the rear of the gun but NOT to cut into the pistol grip area when counter-bored.

Dial indicator in use~

Once indicated in you use a center drill / spot drill to accurately start the hole then drill through using a 1/4" or .250 drill bit.

Once you drill the hole through you remove the drill and I used a 1/2" endmill to counter-bore the "pocket" for the pillar / bushing. Doing it now means its centered the perpendicular to the thru hole.

If you measured correctly your bushing will fit flush and be straight as an arrow.

Bushing test fit (Ignore the Devcon )

See if the screw fits......

Flipping the stock over the hole I drilled through is centered up pretty well and that was a concern. If I did not have the stock positioned correctly the hole would have ended up somewhere unfavorable to me. Some drill from both sides but I am using this hole to position the rear lug tapped hole I will drill and tap shortly. I will insert the action into the stock then use a 1/4" transfer punch to mark the hole location. I basically will slide the transfer punch in the 1/4" hole i drilled then strike it with a hammer to transfer a punch mark where I will drill & tap the 1/4-28 hole in the rear lug.

(That is IF I can find my 1/4 " transfer punch)

Once I have the rear lug tapped I will then finish bedding around the receiver "legs" and actually torque the rear lug / pillar bolt to assist. I have to do some reading to see what the "popular" or correct torque value should be.

More to follow~

 

[jkh62]

If someone knows the suggest torque value for the rear pillar / action screw
please chime in with the suggested torque value.

Thanks , Jeff

 

[SAPPNASTY]

Amazing....Great job and I simply want to see more pics!

-Sapp

 

[Bamban]

If someone knows the suggest torque value for the rear pillar / action screw
please chime in with the suggested torque value.

Thanks , Jeff

I do mine to 65 inch-pounds.

 

[jkh62]

I do mine to 65 inch-pounds.

Noted and thank you.

 

[jkh62]

In the final stretch now......

Tonight its "Tap the lug" night. After I get a threaded hole in the right spot I can then do the final bedding on my rifle and wrap it up.


For those that do not know what a transfer punch is you shall see.... A transfer punch is a precision center punch. Its designed to slide inside a hole and transfer the center point to the surface on the other end. In my case I drilled the hole thru from the bottom of my Mac stock into the rear lug area ( .250 / 1/4" diameter). I wanted to then insert my action into the stock then use the transfer punch to mark where I drill and tap the real lug mounting hole. It worked out pretty good but not perfect. IMHO if I ever do another one I will drill the hole from both ends and meet in the middle.

After measuring the side to side position the transfer punch mark was .030 off center. Since I do not want to purposely drill a hole off center on my receiver I will add clearance to the thru hole in the stock. I had planned to open it up anyway but it bothers me when things are not what I planned.

I will open up both sides and equal amount and blend.

A Transfer punch~

Punch in hole~

Business end~

How you "transfer" the mark~

Once you get the punch mark on the receiver you can then accurately drill the 1/4-28 tapped hole. You set up the receiver as before by indicating it in so its level and square. I use a piece of reamer blank ground to a sharp point. It's this sharp point I use to position it to the punch mark on the receiver I made with the transfer punch. I only have to align it one direction becasue I used my edge finder or wiggler to find the center of the lug off of the receiver. If you have a keen eye you can get it within or under .005. You put the the pointed blank in the spindle and crank the table around to center it.

Once I find the center I zero my readout on the mill. I already have the correct drill, tap, center drill and chamfer tool laid out. Always double check your tap drill size BEFORE drilling the hole. Also its good to have only the correct tooling at hand so no mix up. Don't ask me how I know this....

Center Drill~

Hole drilled and chamfered~

Tapping the hole~

I always start my tap's while its in the machine,they are ALWAYS straight this way. I start them by hand then remove and hand tap, less chance to break a tap when done by hand. In the pic I use a spring loaded tool in the spindle to keep pressure on the tap handle and start it by hand for a few full threads. Use a good cutting / tapping fluid. The Springfield receiver machined up nice and I can tell the steel is of a good quality becasue of the cutting chips produced.

If all goes well you get a mounting hole that will last past my lifetime.

Its a Springfield with a tapped lug ?....They never made any.

Not show was trimming the 1/4-28 stainless steel screw to the proper length. I just slipped it in the stock with my bushing (under the trigger guard) and let it stick thru into the rear lug bedded pocket. My rear lug measures 3/8" thick so the screw should not stick up more than 3/8" or it could be a problem with your bolt travel. I needed to trim and chamfer about .190 thousandths from the thread length and re-chamfer.

I test fit everything again by putting my action into the stock and tightening down the rear pillar and it works without binding or surprises, need to re-blue the rear lug radius.

Now I can go back and do the final finish bedding of my rifle and re-blue the radius I put on the real lug corners.

 

[jkh62]

The final steps and now my bedding project is complete. I wrapped up the remaining "to do" things to complete the stock. My front sling attachment in now in place as well as the remaining stock hardware.


I used stainless steel socket head cap screws and 5/16 (.312) Key stock for retaining them. Its a simple job to mill a 5/16" slot in the stock. The key stock has two tapped holes that the screws attach to. Its secure and can be easily removed if needed.

Screws-

Inside the stock attachment-

This will be a competition gun and a slippery butt stock is a bad thing. I used the spray stick crap and its more of a dirt collector IMHO. I went to Lowes and picked up a roll of adhesive backed traction tape. You have a LOT in one roll but it's durable and leaves no crap on your gun if removed. Trim to size with scissors then peel and stick.

From Lowes-

On the butt-

The stock is done-

Here are some final shots of my bedding. I had extra Devcon mixed up and I like to "paint" the exposed fiberglass stock areas for a uniform appearance.

 

[tonyben]

Looks great!

 

[jkh62]

This wraps up the stock hardware and the stock is ready for the action.
I thoroughly cleaned and greased my new rifle. I greased the bolt roller and all areas that are supposed to be including the stock / ferrule contact point. Once lubed up I placed the action in the stock, torqued the rear lug screw and put the trigger group in place. The trigger group was already stripped, cleaned and lubed prior.

The upper handguard was too long and touching the face of the receiver (bad). There was clearance everywhere else so I was good there. I use dial calipers and scribe a line around the rear lip of the handguard. This gives you a reference line to go by. Its a 20 second job on a belt sander. Sand until you hit the line, deburr and you are done.

Touches receiver = Bad

Scribe a line-

Line-

I am not a huge fan of the brown color handguard so I hit it with some green Fusion paint I had. I am not a huge fan of the green either.....but it works and fits. I put a dab of RTV silicon on the front and rear tabs to retain the handguard so it stays put. This keeps it from contacting the receiver or moving around.

RTV~

Dab in Front-

Some in the rear~

Clears receiver = Good

The final item with a USGI NM flash hider with lug ( I hate the neutered ones)

The twins~

This was an overview of what you can expect "to do" if you bed your own stock or contract it out and have it done for you.


A few thing's I learned along the way~

When test fitting your stock and action BEFORE bedding test for mechanical function. I mean make sure when cycling the op rod and action that the hammer cocks and drops properly. I only tested for proper trigger group lock up and alignment of the action prior to bedding. What I learned after bedding it was the deck height was slightly long. When you pull the trigger the hammer drops BUT if you hold back on the trigger and cycle the action the hammer followed the bolt when it locked up. It would cycle fine if you pulled the trigger, released it then cycle the op rod.

I milled .025 off of the trigger group seating area and the problem is now solved. This was a new gun from a wood stock that was never fired. I should have measured the bedding deck to trigger group length and jotted it down. I am at 1.705" and function correctly.


I like the coat hanger bedding method a LOT. Using the wire I mentioned I have what I would call a moderate amount of draw pressure. Not really heavy and not really light.

Drilling the thru hole for the rear lug pillar / bolt is best done from the top AND bottom directions of the stock. I added clearance but drilled from one side only ( bottom ).

I love working with Devcon 10110 steel putty, its by far the best compound I have ever used and seems to hold up very well.

Bedding the M1A is similar to putting ceramic floor tile down. Its not quick and easy nor hard to do but time consuming and each step needs to be done correctly before moving on.

After torquing the rear pillar screw use a punch and make an alignment mark on the screw and pillar. If in the field and you need to remove it you can get it close without a torque wrench.

My rear pillar / bushing is Devcon secured in place.


Now to get a day above freezing temperatures to hit the range.

 

[jkh62]

Good job! By the pics, I take it that you are not planning to bed the front of the receiver; correct? If you aren't you might want to consider it.

Tony.

I did but I sneaked it in.......

GBERET1

In my situation I needed to remove the action to do the rear pillar work and place it back in the stock for measurements so you guys talked me into doing the front section as well.
I do not like removing the action and putting in back in the finished bedding unless I have to,

 

[chefcam864]

Fantastic work! Thanks for the pics and expert description. I am nowhere near ready to bed my M1A, but I have a MUCH, MUCH better idea of what is involved. Again, good work and thank you.

 

[Jersey Devil]

This is an awesome thread!!

Very inspiring. Great work, and great photos!!

Thanks for sharing this process with us.

 

[duke54]

One Helluva Job there Skippy! Extreme attention to details ! I Do Like it very much!! I still ask myself why I sold the bridgeport, the lathe and the Syncrowave 250? I guess thats a whole nother story. Kudos to You!!!

 

[Lone Ranger]

Great job and looks good. Your explanation was detailed but easy to follow and the pics were great and added to understanding the steps you took.

 

[tonyben]

If someone knows the suggest torque value for the rear pillar / action screw
please chime in with the suggested torque value.

Thanks , Jeff

55 inch pounds

 

[SteveInOregon]

The BEST photo sequence and explanation I have ever seen on a firearm topic. BRAVO.

 

[jkh62]

The BEST photo sequence and explanation I have ever seen on a firearm topic. BRAVO.

Thx!