Gunsmithing Recoil Lug Pin

[Army First]

Know where to get one for a Zermatt Bighorn SA?

About 15 mins ago I pulled my barrel and found I had managed to bend the pin in my recoil lug on a Bighorn Origin SA.
I have sent a message to Zermatt but until they respond I can't find them online.

 

[Bradv86]

Zermatt is your best bet. Have you measured the diameter? A place like McMaster
probably would have some precision pins or rod to cut if you are trying to repair it very quickly. No guarantee at all that they would have the right size, material, or hardness.

McMaster-Carr

McMaster-Carr is the complete source for your plant with over 595,000 products. 98% of products ordered ship from stock and deliver same or next day.

www.mcmaster.com

 

[Army First]

Zermatt is your best bet. Have you measured the diameter? A place like McMaster
probably would have some precision pins or rod to cut if you are trying to repair it very quickly. No guarantee at all that they would have the right size, material, or hardness.

McMaster-Carr

McMaster-Carr is the complete source for your plant with over 595,000 products. 98% of products ordered ship from stock and deliver same or next day.

www.mcmaster.com

Thank You

 

[Army First]

Zermatt sent an email this morning before 8am wanting an address. Problem resolved

 

[Terry Cross]

Zermatt sent an email this morning before 8am wanting an address. Problem resolved

Typical. (for them)
They are on the ball and top shelf.

./

 

[LRI]

FYI on pins...

A lot (like darn near all of em unless otherwise specified) of pins bought in bulk from places like McMaster, MSC, or whatever are case hardened. When you get to the small stuff, .094, .06, etc... it is VERY easy for the case to penetrate a bit more than maybe what's intended. That or it's just so small to begin with that it begs for failure in a shear load environment. An example is that casing a part .015" deep isn't all that uncommon. On a 1/16th diameter pin that's approaching 50 percent of the diameter. It makes the pin hard as woodpecker lips, but it also becomes a whole lot more brittle.

It does not take a whole lot of shear load to snap one. (as you discovered) It's been my experience that annealed pins are much better for this job.

Last:

If you guys ever have one of these things snap off in the receiver and you don't have the tools to get it out forensically, PLEASE STOP AND CALL US. I've fixed literally hundreds of these for shops all over the states on a variety of actions.

Leave the Dremel, torch, welder, hammer in your toolbox.

 

[Hateca]

These are one of those thing that are a hold over from quick change benchrest rifle builds where barrels are literally tightened with hand pressure no tools. They are not meant to take lots of torque Like in a field gun or tactical rifle build. The pinned lug in my opinion for these builds is for returning the lug to the same orientation. When I torque a barrel I still use a lug jig to keep the lug from trying to spin and put load on that pin.

 

[LRI]

These are one of those thing that are a hold over from quick change benchrest rifle builds where barrels are literally tightened with hand pressure no tools. They are not meant to take lots of torque Like in a field gun or tactical rifle build. The pinned lug in my opinion for these builds is for returning the lug to the same orientation. When I torque a barrel I still use a lug jig to keep the lug from trying to spin and put load on that pin.

I would argue that pinning a recoil lug checks a box that goes far beyond the BR game. It has a lot to do with how well a bedding job comes out.

Example:

You bed up a rifle and once finished, the barreled action comes apart in prep for final finishing. Upon final assembly, you diligently use your little tool to try and index the recoil lug. Only it's off by say, a single degree. At only one degree worth of rotational error, the bottom corner of an M700 profile recoil lug is out of position by .02" of an inch. -Roughly the thickness of a matchbook. Most would counter that problem by saying that is why you wrap a couple layers of tape around the periphery of the recoil lug. That will certainly help, but it's still very possible to end up with the lug biasing how the entire receiver registers in the bedding job. It ends up becoming a bandaid fix. The other possible argument is just to put the thing together first and bed it last. While that is certainly doable, the fit/finish expectations of today's shooter more or less command that the job be as clean as possible upon delivery.

With the best of intentions the stuff now gets squashed back into the stock only now trigger features rub on the inlet, the guard screws don't wanna line up correctly, and the barrel starts to veer off in some odd direction that it shouldn't. All because of a little dickhead recoil lug that doesn't want to repeat the clock position.

I cannot count how many times over the years this has kicked me in the nuts. The decision I made years ago is that it's far less "drain bammage" to just pin the darn thing and be done with it. It's been a cardinal rule for us for about 5 or so years now.

 

[Mike Casselton]

To tag what Chad just said.
I recently had a barrel replaced and asked that the original recoil lug be used and oriented based on the witness mark.

My reasoning?

I still have the old 6-BR barrel for it and I'd like to continue using it.
It's also bedded for a composite Winchester style Marksman stock.

I get it back and the mark is just a RCH off. Almost not noticeable.
When I put it back into the stock, the exact and I mean exact issues Chad mentioned are now present.
The action no longer sits completely in the bedding. The rear screw is off a tiny bit and the barrel now sits on the right side of the channel...

I ended up moving it to a B&C 5 because the bottom of the lug didn't make contact with the bedding block.

Now I have a stock that I can't reuse for the original barrel.

 

[spife7980]

I get it back and the mark is just a RCH off. Almost not noticeable.

 

[Mike Casselton]

Juss a little tippy tap.

That thought has crossed my mind.

 

[Army First]

Typical. (for them)
They are on the ball and top shelf.

./

My FYI follow up.

They sent the package UPS and they included 3 spare pins. (4 total). Really really good CS from Zermatt

 

[Hateca]

I would argue that pinning a recoil lug checks a box that goes far beyond the BR game. It has a lot to do with how well a bedding job comes out.

Example:

You bed up a rifle and once finished, the barreled action comes apart in prep for final finishing. Upon final assembly, you diligently use your little tool to try and index the recoil lug. Only it's off by say, a single degree. At only one degree worth of rotational error, the bottom corner of an M700 profile recoil lug is out of position by .02" of an inch. -Roughly the thickness of a matchbook. Most would counter that problem by saying that is why you wrap a couple layers of tape around the periphery of the recoil lug. That will certainly help, but it's still very possible to end up with the lug biasing how the entire receiver registers in the bedding job. It ends up becoming a bandaid fix. The other possible argument is just to put the thing together first and bed it last. While that is certainly doable, the fit/finish expectations of today's shooter more or less command that the job be as clean as possible upon delivery.

With the best of intentions the stuff now gets squashed back into the stock only now trigger features rub on the inlet, the guard screws don't wanna line up correctly, and the barrel starts to veer off in some odd direction that it shouldn't. All because of a little dickhead recoil lug that doesn't want to repeat the clock position.

I cannot count how many times over the years this has kicked me in the nuts. The decision I made years ago is that it's far less "drain bammage" to just pin the darn thing and be done with it. It's been a cardinal rule for us for about 5 or so years now.

I didn’t say I don’t pin, in fact I do for the bedding reason you mentioned, but I also use “my” lug tool to keep that pin from shearing off or bending as in that photo. Not sure what lug tool you’re using or have seen used but I can assure you the tool I use isn’t going to allow that lug to move under any amount of torque and the pin never gets bent or broken, and it will always drop back into the bedding like it never left. It’s all how the original cake was baked and what ingredients were used. Haven’t had a problem doing it this way for almost 30 years.