I have been working on a Rem 700 .222 salvaged from a SD Ranch truck. I am not a pro gunsmith, but at 81 so I am very well acquainted with guns. I got it stripped down and clean as best I could, I saw the barrel was rusted on the outside and terribly pitted on the inside. I found another new (?) takeoff barrel and am now trying to fit it to the receiver.

I am using the old barrel recoil lug and an within 1/8 of a turn to align the sights, barrel and receiver.. I have looked for another lug for it and find the thickness usually advertised at .250. The old lug I had with the original rifle measures .186.

My question is this, does the lug thickness have to do with headspacing, and would taking .005 - .009 off of the surface to allow for sight alignment, drastically alter headspacing.

I have a gimme rifle with a little money in the parts, but if I have a huge headspace bill, should I just give up and junk the whole project?

Any help here would be greatly appreciated.

Bill Martin
Live Oak Texas

Anything you take off the lug will shorten headspace. You need to measure your current headspace to see if you can take the required amount off the lug or barrel shoulder and still be okay.

And even THEN the sights will probably not be in line..

My advice? Either drop the project or take it to a 'smith that has the proper tools (i.e., lathe) and have it (gender neutral, LOL) do it right..

FWIW.

Another old guy here that likes to save a buck. It will take very little to turn the barrel another 1/8 of a turn. In fact just cleaning everything very well including the action threads might get you the 1/8 turn. You will still have to check the headspace. Be sure you use an action wrench to tighten. Too tight of headspace is easy to fix (rent a reamer), too loose needs more work.

It is a relatively simple math equation to determine change in headspace.

Thread pitch is 24 (I believe). So, there are 24 threads in 1" of length and 0.042" in one complete turn of the barrel. For 1/8 of a turn, that's 0.005" of headspace change.

Hi Bill.

The thread pitch is 16. But that's not really relevant to your situation.

My first question would be...where is the headspace at when the barrel is tightened? It's been my experience that 700 factory barrels will headspace pretty well when swapped around even if the sight holes and stampings aren't perfectly aligned.

If it's ok and you can live with the front sight holes being off relative to the receiver, you're in good shape.

Once the barrel comes up tight to the receiver and assuming reasonable flatness of the mating surfaces, there won't be more than .0015-.002 (at most) that you'll be able to change the headspace no matter how much you turn the barrel to continue tightening it. At that point, the threads are what's stretching...not the recoil lug compressing.

If the headspace comes up a bit short, you can always shorten the shell holder a bit. If it's a few thou long, you can get around that too.

Hope this helps. -Al

Al did his usual good job,but then again he actually shoots,which is an obviously "unfair" advantage in said discussions and readily apparent from those who HILARIOUSLY missed yet again in their efforts. Hint.(grin)

The cited .186" OEM lug is well within the realm of Big Green's "normal" and the .250" aftermarket lugs are for barrels other than Factory and are a nice round number,that's Warm & Fuzzy. As cited,removing lug thickness,changes headspace the identical amount,of said material's thickness. If Reloading,that is easily controlled,but if you are rolling Factory Fodder,there's is a likelihood of having issues. Positive Headspace is an exceptionally good thing in my book,as it bolsters case life,accuracy and safety,none of which are "compromises". Hint.

I personally put far more store in Safety,than I do Aesthetics and I'd quantify same,then pursue as required to connect both dots in unison,within that order. Hint..................

If you don't know what you're doing, it is generally prudent to pay someone who does it for a living and can do it right, IOW a professional.

I've rebarreled dozens of Remington rifles and almost always have to set the barrel back a few thousands of an inch to get the roll stamps to line up where the factory intended them to be. If the barrels hadn't been factory d&T for open sight and I didn't care where the roll stamps ended up, setting the barrel back wasn't an issue.

Doing a workaround for yourself is okay, but what about the next owner?

I am not a 'smith, just a guy with a lathe, a mill, and enough knowledge to know his limits.

Thanks Al I have digested all of this and more from the Greybeard folks, and I would like to thank all of you for the advice and points that you have made. I'm not new to guns and mechanics, but never tinkered with a Rem 700, all of this put a lot of stuff in perspective for me. I think the amount I need to take off to align it all will be very minimum. I also believe that I can probably get around a little head space in reloading, but will proceed with my first intent, keep cleaning the rest of the gun, slim down the .186 present recoil lug to probably .180. finish up the repairs I can do and take the gun to a good gunsmith, to have the head space checked. I am thinking with your advice and what I know, I can get this 700 shooting coyotes again this fall.

BTW this rifle came out of my brother in laws ranch truck, several years ago. He towed in to his boneyard and forgot the rifle was in it, until I came nosing around while shooting P Dogs on his place. I spotted the rifle and asked him,if he wanted me to try and repair it. OF COURSE the answer was, yeah see what you can do for it. So I am trying to do him a favor and get it back in another truck, sort of pay forward, he has taken care of my hunting needs for years no, it is the least I can do for him!

So thanks guys, my 81st birthday was lst week, and you have given me the confidence to get er done!

I'd be inclined to index the barrel in the preferred alignment(without lug),to ascertain bolt nose clearance,amongst other things. From there,the shoulder/receiver face "gap" can be measured,if only to pinpoint more. Won't cost you anything,other than a few seconds of time. Hint.

Plate glass,a few drops of water and 200# wet/dry can do wonders. Hint................(grin)

I would caution against taking .006 off the lug before checking anything. You need to keep in mind what else that changes besides the physical headspace....you also need to stay out of trouble with the bolt nose.

As 'Stick correctly mentioned...you need to know where the bolt nose is relative to the counter bore in the rear of the barrel. Most factory 700's will have about .012-.015 for bolt nose clearance. But I've also seen them with as little as .005.

Even on a tuned up 700 action where everything is straight and flat, .010 is the tightest bolt nose clearance I want.

Lacking the measuring equipment to check this, there's an easy way to determine this clearance.

Just a heads up.... -Al

A great "heads up" Al... Kudos.

Unless my fumble fingers and brain did something wrong, we are talking 0.007' to make up 1/8 turn.
Not sure what (percent of one turn) is from snug to "Tight" is for a barrel.

Amazing to think what I would do, vs commit to keystrokes on he internet.

Thank you.

As a quick and dirty way of checking bolt nose clearance, I use the lead 'squirts' from my .30 cal. bullet making. A dab of grease on the counter bore, put a 'squirt' on it and close the bolt You can then remove the 'squirt' and measure the thickness...kinda' like Plastigage if you've ever used that.

When compared against an indicator measurement, it's always within .001 ....which is likely the film thickness of grease after compressing.

Good shootin' -Al

Plastigage, an engine builders best friend (or worst enemy depending). I have not thought about that for years.

A small piece of #9 shot or a small fishing sinker might work if you have one of those handy

For the purpose of discussion, here's my Panda HV gun. I make a witness mark where the barrel comes up as tight as I can get it by hand. Then after torquing it to 120 lbs./ft., I make another witness mark. You can see how much 'advance' there is as the 60 degree threads load up.

Headspace changes maybe .0005 (half a thou.) from one witness mark to the other.

The other nice thing about witness marks is on subsequent barrel changes (like testing barrels at the range), all you have to do is line up the witness marks and rock on......

Good shootin' -Al

That's interesting info worth noting, thanks.

While I'm not a professional 'smith,, I've never 'found ' more than .002 headspace change from firmly hand tight to adequately torqued when swapping barrels and lugs that haven't been corrected on to uncorrected receivers. In other words....all factory parts.

The flatter/straighter mating pieces are, the less the headspace will change from firmly hand tight to torqued pretty aggressively. It's the thread stretch that keeps things tight...not the flat-flat engagement surfaces. Once you reach a certain point, more tightening just continues to stretch the threads.

You can get a pretty good idea how things are fitting with some Dykem on the mating surfaces and a light oil on clean threads. If the barrel 'snaps' loose instantly, the Dykem will show pretty decent contact with very little 'smear'..

Again...just my 2 cents worth. -Al

Depends a bit on shoulder contact area as well. Most BR rifles will have a full 1 1/4 inch shank so there is a lot of shoulder area. It was SOP to leave .002" for "crush" when chambering, when I started out. and it seemed to work out pretty well. This on unaltered actions.
On actions like a Mauser, when the barrel is tightened on the inner seat, it ain't movin' much further, no matter how hard you hit it.
Like Al says, the better the fit, the less movement you will see. For an eighth of a turn, a quick and dirty method to gain some movement is to smear some JB on the threads and crank it in and out a few times. GD

A picture is worth a 1,000 words as they say…

Here you can see how the recoiled lug width is part of the barrel tenon length

You should also figure out really fast that the headspace is the controlling dimension, so the resulting bolt nose clearance is something you live with.

Al called it - most Remy factory guns have 15 thousands clearance between the bolt nose and the ring, and cut (depth and width)…
I set mine a heck of a lot closer (I don’t use a reamer I cut the nose recess based on the bolt size…

The “fun part” is that non-sealing actions like Savage… guys are just screwing things in - if you EVER got a short chambered barrel by mistake… GOOD GOD you’d have unsupported case wall… because you’d have excess bolt nose to barrel clearance.

Exactly how I did those also... I usually left .005-.006. Easy to do with a depth micrometer..

5-6 thousands is what I use as well..

A slight veer off track but here goes...a few years back at an IBS tournament, a friend was having issues with his BR gun tossing a shot into the condition when the flags showed it should have dropped right in. He asked me to look it over and with a stripped bolt you could just feel a little snick when it closed. A black marker on the end of the bolt nose showed it was lightly contacting the counterbore.

I did a bit of careful dirt clod 'massaging' and the gun shot dots.

For what it's worth. -Al

Just a quick mention....for the home hobbiest, a piece of solder also works slick to check bolt nose clearance.

The advent of pre-fit barrels with nuts has opened up all sorts of issues. Some of the machining on these barrels can lead the installer into a downright dangerous situation....especially for nosed bolts like the 700s.

Be careful out there..... -Al

Good timing. Here's a 700 fired case that had .008" bolt nose clearance. The owner failed to clear his throw and fed some red dot with the 4350.

Had the clearance been much over .015, I'm thinking it may have blown out.....less gets ugly as mentioned above.

I have a dozen or so lugs on hand, most with a thou or two difference in thickness.i can generally get any 700 takeoff to head space good by switching lugs. The roll marks rarely line up. If you want all the markings in the right place you will need a reamer or a lathe