Simple Cross Pin Jig - Part 2

Well, I don't have a ready source for binder pins, and besides I had this brain storm idea that I also wanted to try out. (Nothing to loose since I can always revert back to the 1/4" cross pins)

I found these 1/4-20 x 1-1/2" bolts called "connector bolts" at Lowe's.

So backing up to the last step, I didn't drill out the trigger guard to 1/4". Instead I drilled it with a 13/64" and tapped it 1/4-20. I have no idea if anybody has ever tapped the trigger guard and simply threaded bolts in from each side, but these "connector bolts" with their nice big and flat heads looked like a natural.

So I figured half the width of the stock at this point and cut off two of the connector bolts. Slightly round and chamfer the cut ends for an easy fit to the threads.

The "connector bolts" have a small bevel under the head, so I chamfered the holes to allow the bolt heads to seat flush.

Here is what one bolt looks like half way through the stock.

Both the bolts in position. You can't see it in the picture, but there is a small gap between the ends.

Seems to work okay, and heck for stout.

I like the low profile and large bearing surface of the bolt heads.

Edited at a later date to add
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This receiver and trigger guard have been altered such that you can't readily switch it between the cross pin altered stock and an unaltered stock. However, there is an easy fix to add to the versitility of this mod.

Simply secured the rear cross pin holes with two 1/4-20 x 5/8" hex set screws. I couldn't find a 5/8" so I just shortened two 3/4" setscrews.

Drive a setscrew flush from each side. Tighten them against each other.

Good to go in a regular stock now.

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End of edit

Here are a couple of peek shots of the project rifle build. It's still a work in progress at this time.

A little disclaimer at the end here.

What I've illustrated here was a spur of the moment one time problem solver. This simple jig worked for me but experience is your friend when drilling the holes and getting the tip of the drill to come out where you want it. I used a drill press and made darn sure that the side of the stock was perpendicular to the drill bit. Anybody wanting to try out this idea on an expensive stock might want to practice on their old takeoff stock first.

When I got all done with this project, I did a search and found a picture of the cross pin drilling jig that bhigdon101 rented out for a while. I see that I used the same basic idea that his machinist used, although his is a super heavy duty unit machined from a single block of steel (?) and ought to stand up to hundreds or perhaps thousands of uses.

 

Excellent post Hipshot. Thanks for sharing.

 

Very well done.
Thanks

 

an EXCELLENT post as always by the master stock maker himself. 5 stars and please make this a sticky.

 

Awesome idea, and Looks Great, Hipshot!:t:t

You're braver than most, to drill through a factory receiver (or any receiver, for that matter), as I'd never do it, no matter how careful I am with it!

I've been working on my own version of Brian's stock pinning jig, but you've just given me an even easier solution idea!

Any plans to put that stock in production? WAY Cool Profile on that one!

 

Excellent write-up. i kept saying "O...M....G" everytime I saw a drill bit. Looks solid


now, what I dont like is that the stock shows the hole for the bolt stop pin. kinda funky. Since you custom made the stock, why not bring the wood all the way up and have it cover the hole like a factory fit? maybe you can tell me something im not understanding.

 

Excellent write-up. i kept saying "O...M....G" everytime I saw a drill bit. Looks solid

now, what I dont like is that the stock shows the hole for the bolt stop pin. kinda funky. Since you custom made the stock, why not bring the wood all the way up and have it cover the hole like a factory fit? maybe you can tell me something im not understanding.

Well this stock was really just a test bed for several ideas that I wanted to try. The exposed back of the action is just a style. (Even the Tomahawk stock used it.) A black buffer is not so noticable. It's just a look I was after and would really like to have one of the aftermarket "square backed" receivers. The original NODAK comes to mind.

Here is a profile shot of this stock.

As far as the style of this grip, I was trying to get some of the feel of the McMillan "gooseneck" look of the A-5, etc. stocks. Running the back of the stock all the way up like normal would have killed this look. That little "gooseneck" shelf is actually a thumbrest.

Photo is from McMillan website.

I got the idea to try the cutaway back while I was working on the stock pictured below. This one has the wood all the way up the back like normal. As you can see, it's just a drastically different look.

 

Brilliant!

 

jig

awesome setup just one more project for me thank you I was wondering if they make a channel in aluminum large enough to setup both sides at once but a very great idea :AR15firin

 

great post and good thinking on your part. wizzr

 

Sweet!

Hipshot...

Great write-up on your jig building and pinning process. Gotta admit, the pins you used actually go really well with the stock you have designed / built.

Im not really big into the target theme but I do really like what you have done.

I am going to save the link to this post so I can recall it if I ever decide to do a receiver pin job.

Thanks for sharing your work...

Silvertp

 

That is an inspired idea!

Well done!

 

Now that is way Kool!:bthumb:

 

Why only cross pin from the rear and in a new hole, rather than use existing hole in the receiver trigger group. Only reason I can think of is the possible difficulty lining up holes. Please excuse my ignorance if this is a DA question.

 

Actually this jig is designed to use the existing hole(s) in the receiver and trigger group. The purpose of the jig it to drill the cross pin holes in the stock as closely as possible to the required location.

I included several options in this thread.
(1) Drill a 3/16" cross pin hole in the stock and use a 3/16" binder pin. I only showed the rear hole, but just follow the same procedure to drill a hole for a front binder pin if desired. (The factory pins are 3/16".)
(2) If you prefer to use a 1/4" binder pin, then you will need to drill out the existing 3/16" holes in both the receiver and the trigger guard (and the holes in the stock, of course).
(3) I found the big headed "connector bolts" pictured above and wanted to try a little different twist. I drilled out the receiver and stock holes to 1/4" then threaded the rear hole in the trigger guard to 1/4"-20. Instead of using one pin that goes all the way through the stock, I just inserted a "connector bolt" in from each side. It's just a different approach and I don't know if anyone else has tried it. Ideas are free.
I recommend #1 above. Depending upon your requirements, you can do just the rear cross pin or do both the front and rear.

The reason for doing only the rear cross pin is to accomodate an adjustable bedding method. A piece of innertube or other compressable material is installed in the barrel channel just ahead of the action. The rifle is then field tested using a varying amount of torque on the takedown screw. (An adjustable torque screwdriver is definitely going to be your friend here.) This usually further requires the installation of a bedding pillar to prevent unwanted compression of the stock by the takedown screw/escutcheon.

If you want to totally lock the action into the stock, then install a cross pin in both the front and rear holes. This brings us to a discussion of the various merits of fully free floating a barrel vs the various techniques for bedding the barrel.

This is only a very superficial discussion of bedding the action or the barrel and I certainly defer to those much more knowlegable than me.

 

Excellent idea and write up Hipshot! Do you have any range reports?

Great job on your stock also.

 

Excellent topic, step-by-step instructions and workmanship...:bthumb:

 

Thanks for the writeup :bthumb:

I used your idea with one modification and it worked perfectly. Since the jig material is thin, in order to assure the bit is started straight, I epoxied a bronze bushing with the correct ID to the outside of the jig and let it cure with the drill bit holding it in alignment with the receiver and jig holes.

Not exactly professional grade, but it worked slick.

 

Great idea m0par and a very nice improvement.:t If you get a chance, post a picture of your jig for anyone else who might want to try installing cross pins.

While the idea for a simplified jig was my idea, I definitely want to point out and give credit to Ole' Man River as the person who initiated the idea of cross pins to anchor the receiver to the stock.... a truely inspired idea.

Hipshot

 

Hipshot- Thank you for this great tutorial! Definitely will help with my build. OK, now for a couple of newbie questions.

Since you are anchoring the reciever, does this eliminate the need to bed the action?

If you are going to pillar bed, anchor the receiver and bed the barrel, would you do it in that order, or is there another sequence that should be done?


Thanks for the help!

 

i was wondering if the connecctor screws had a hex head on them, i couldnt really tell from the pic, thanks:AR15firin

 

Wouldn't a "through bolt" be preferential to using two individual bolts from either side... I ask because that is what I had in mind for cross pinning two Barracuda stocks??? If a through bolt is used... what would be the best hardware to accomplish this???

 

I don't know if its preferential or not, but I used a 1/4" diameter standoff with 10-32 machine screws and countersunk washers from McMaster-Carr.

91125A503 Female Threaded Round Standoff
92918A140 Black Zinc-plated Brass Countersunk Washer
96640A141 Flat Head Phillips Machine Screw

The standoffs aren't threaded all of the way through, but are threaded deep enough that they should work for nearly any width stock if the length is trimmed equally from both sides.

You could probably find a size that fits the existing hole in the receiver/trigger housing if you didn't want to open it up to 1/4". The screws would have to be smaller diameter, but that shouldn't be a problem. If the standoff is trimmed to the right length, all the screws are doing is keeping the standoff from shifting left or right.

 

Talley

another post talked about "Talley bolts" used to strengthen magnum caliber stocks. Midway has them under part #752327. Kuna Gary

 

another post talked about "Talley bolts" used to strengthen magnum caliber stocks. Midway has them under part #752327. Kuna Gary

Can anyone verify how long of a bolt you need to start with for this? The Talley measures at 1-3/8" long according to the brownells website.

I would go measure my carbine stock, but my 10/22 is about an hours drive away at the moment...

 

It’s just short of 1-5/16” across the inletting of my DSP. It’s ~ 1-13/16” across at the widest point outside.

 

Would this idea work?

How about using music wire (that tempered-steel stuff like they sell in many diameters for RC model airplanes) to create a replacement pin for the rear hole, only the new pin would be long enough to reach all the way across the stock?

This would leave the receiver and trigger guard stock. The new pin would be a single rigid piece. The pin could be secured on both ends by locating a short wood-screw next to the pin, so that the head of the screw held the pin flush on each side of the stock.

What is the original pin diameter, something like 3/16? A single piece steel pin should be pretty stiff, at least as stiff as bolts screwed in from both sides.

 

Absolutely brilliant Hipshot! Thanks not only for the design but your detailed information/description /design. I have a few stocks I want to do this to after I build the jig. Will also see if it will be suitable for drilling my Pmaca chassis . Now to start gathering materials and begin. Thanks again!

Paul

Sent from my HTC0P3P7 using Tapatalk

 

Actually did this on a TROY chassis for a customer. Used Hipshots method, with a few tweaks for the application at hand. Worked out really well with no issues.

Turned out pretty nice and very solid. I drill and tapped the trigger group in this case.

 

Nice tutorial!