I have an M700 in 300 RUM that I want to re-barrel to 338 RUM. I will be having a barrel made by Pac-Nor and want to attach and headspace it myself. It is more of a do-it-myself thing than saving money. I have re-barreled a few Savages and want to try my Remingtons now.

As far as I know, I just chuck the barrel between centers and turn down the shoulder. then check headspace using gauges, then turn/check agian as required. Is it as simple as it sounds? How much torque should I use when attaching the new barrel?

I have an action wrench that fits the action, I just need to make a barrel wrench (or buy one). Does heating the barrel/action help when breaking the old barrel loose? Thanks.

Ranb

When mine was changed we used a barrel vise from Sinclair International that worked good with the action wrench and no heat was needed.

quote:

Originally posted by ranb40:
I have re-barreled a few Savages and want to try my Remingtons now.

As far as I know, I just chuck the barrel between centers and turn down the shoulder. then check headspace using gauges, then turn/check agian as required. Is it as simple as it sounds? How much torque should I use when attaching the new barrel?

I have an action wrench that fits the action, I just need to make a barrel wrench (or buy one). Does heating the barrel/action help when breaking the old barrel loose? Thanks.

Ranb

Unfortunately the experience you gained with rebarreling the Savage won't have prepared you for the Remington. True, they both use threaded barrels, and the headspace is measured the same, they are different in that the Remington has a special machined area for the bolt nose, a free spinning recoil lug and it doesn't use a barrel nut. Headspace has to be dead on the first time, or, you may have to make adjustments to the entire breech end of the barrel.

What would probably be ideal here, would be for you to place a Savage barrel and your Remington 300 RUM barrel side by side and compare the two. The difference will be apparent.

At the least, you will need to transpose and duplicate the dimensions from the Factory Remington Barrel, to that of the Pac-Nor barrel. Everything, including shank length, the bolt nose recess and diameter needs to be the same.

Pull the firing pin and close the bolt. On the receiver, headspace is measured from the front of the recoil lug to the bolt face, and on the barrel, from the shoulder to the chambered headspace gauge.

You probably won't need to apply heat to remove the barrel from the Remington. As far as torquing the new barrel into place, just pull the action up until she's good and tight. You shouldn't need to beat on it with a hammer to seat it. Don't forget to mark the barrel for the correct caliber. Good luck!

I am well aware that the Savage is much differant than the Remington.

I am planning on ordering a Pac-Nor pre-fit barrel. It comes ready to attach except for the short thread shank to be set back for proper head space. All I have to do is trim back the shoulder ahead of the threads to get the proper headspace, correct? Thank you for the advice in your post.

Ranb

From Pac Nor web site. Pay particular attention to the last parenthetical sentence.



Prefit barrels have gained acceptance with gunsmiths in the U.S., as well as most foreign countries. The prefit barrel comes to you with a short thread shank to be set back for proper head space; completely contoured, polished, handlapped, threaded, chambered, crowned, headspaced, and fitted to the action. (All prefit barrels should be fitted and headspaced only by a qualified and competent gunsmith.)

And this is how i will learn to do it, if it is not too hard.

Ranb

quote:

Originally posted by ranb40:
I am well aware that the Savage is much differant than the Remington.

I am planning on ordering a Pac-Nor pre-fit barrel. It comes ready to attach except for the short thread shank to be set back for proper head space. All I have to do is trim back the shoulder ahead of the threads to get the proper headspace, correct? Thank you for the advice in your post.

Ranb

The problem with pre-fit barrels is that if the person installing the barrel accidentally takes off too much material, then he is faced with some additional work he may not be prepared to do. All I can say is go slow, measure twice, cut once. When setting the headspace, don't forget to allow for the crush.

As long as you are careful in your lathe set up and remember that it’s easier to remove metal than it is to put it back on you should be fine. Use a steady rest and place it as close to the work area as you can. You want your set up rock solid.

That shoulder MUST be cut so you get 100% contact between the shoulder face and the recoil lug, and to get that your facing cut MUST be at 90 degrees to the bore axis. I find it really helpful to lock the carriage so there is no chance that the cutting pressure will try to push the tool away from the should as it travels. What you are trying to do is remove any chance of there being even the slightest amount of right or left longitudinal movement of the cutting tool. Ask me how I know this.

If you don’t have a properly ground facing tool there is a good chance of leaving a slight ridge right where the shoulder meets the thread tenon and that will prevent the shoulder and the recoil lug from seating up flush. You need to grind and shape your tool so it can get all the way into that “corner†but without getting into the thread tenon. And ask me how I know this one too.

Use a nice sharp tool and take very light cuts, and lots of measurements.

quote:

As far as I know, I just chuck the barrel between centers and turn down the shoulder

You will need to recrown the barrel if you face the shoulder between centers.

And then, when you get it between centers, notice how it "lopes" from not being straight and wonder if your new shoulder is anywhere near being perpendicular or concentric to the bore.

quote:

Originally posted by pointblank:

quote:

As far as I know, I just chuck the barrel between centers and turn down the shoulder

You will need to recrown the barrel if you face the shoulder between centers.

I wouldn’t mount the barrel between centers for this job but Brownells has some little brass cones called “Crown Savers†that work great if and when you do have to place a center in the muzzle.

I should have said I was going to put the muzzle end into the work holding chuck, and the live center in the chamber end. I have a steady rest I can use if it holds it straighter.

If things do not look right after I get it turning in the lathe, I will bring the barrel and action to a qualified gunsmith to do the job. Worst case is I learn a $280 lesson in how much I need to learn before I try this again.

I am making a barrel bushing to hold the barrel in my vise while I crank on the action with my action wrench to remove the old barrel.

Thanks for all the comments and advice guys.

Ranb

quote:

Originally posted by ranb40:
I should have said I was going to put the muzzle end into the work holding chuck, and the live center in the chamber end. I have a steady rest I can use if it holds it straighter.

If things do not look right after I get it turning in the lathe, I will bring the barrel and action to a qualified gunsmith to do the job. Worst case is I learn a $280 lesson in how much I need to learn before I try this again.

I am making a barrel bushing to hold the barrel in my vise while I crank on the action with my action wrench to remove the old barrel.

Thanks for all the comments and advice guys.

Ranb

Hey pardner, at least you are responsible enough to learn on your own stuff!

Chucking the shank up in a 3 jaw will surely lead to trouble. I would venture to say that very few bores will run concentric with the outside of the barrel, probably almost none. The only way to do this properly is with an adjustable chuck, either a 4 jaw or an adjust-true. Then the bore needs to be indicated in, not the outside of the barrel. If you don't have an adjustable chuck, you can usually find just what you need on ebay...for a fraction of the new price. I picked up an 8" Buck 3 jaw adjust-true with backplate for 1/10th of what I would of paid for it new.

quote:

Originally posted by ranb40:
I should have said I was going to put the muzzle end into the work holding chuck, and the live center in the chamber end. I have a steady rest I can use if it holds it straighter.

If things do not look right after I get it turning in the lathe, I will bring the barrel and action to a qualified gunsmith to do the job. Worst case is I learn a $280 lesson in how much I need to learn before I try this again.

I am making a barrel bushing to hold the barrel in my vise while I crank on the action with my action wrench to remove the old barrel.

Thanks for all the comments and advice guys.

Ranb

Since the barrel is pre-fit, you are stuck with Pac-Nors set up. Hopefully all you are going to need to do is adjust the shoulder to set the headspace and nothing else. Pac-Nor has a pretty good reputation and so I would imagine that they go the distance to make sure that their work is pretty straight. You don't stay in business very long screwing things like that up.

To make the best of the situation were I you, I would place the barrel between centers to cut the shoulder. For the muzzle end you can do as fyj suggested with the brass muzzle protectors, or, go with direct contact and then cut a new crown. After you have calculated and re-calculated the exact amount of material you need to remove from the shoulder, having allowed for the crush, make the cut. If however you made an error in your calculations, that will be good for another thread! Literally. Good luck!

I am stuck. I have the required action wrench, and I made an aluminum split bushing that fits the taper of the barrel where it meets the action. I tighten the bushing around the barrel using my vise, but the barrel rises out of the bushing when I turn on the action wrench.

The barrel is one of those light-weights with a continous taper from breech to muzzle. How do I keep the barrel from moving out of the bushing while I turn it? I tried using sandpaper to grip the barrel, and a gritty powder made for scope/rings, but the barrel still slides out.

I may need to break down and buy a barrel vice. How well does Brownell's barrel vice work? It might be $154 well spent. Would a steel bushing work better than an aluminum bushing? Thanks.

Ranb

I wanted to change barrels on my 700 Rem. So I also tried to make a barrel vise to remove the barrel, didnt work. So I took it to a gunsmith and for $15.00 he removed the barrel. My home made vice works very well in removing and replacing the barrels now. It is true I don't get them as tight as factory, but they work on the gun fine. I think the parts to make the vice setup cost about $10.00.

malm - best advice I've heard for years
Measure twice cut once

Brownells just put out a fine article on rebarreling . They are not using a prefit but some of the info should be helpful. It would be worth your time to ck out thier site.
Wayles

Some of the bushings I have for tapered barrels I have I made using an aluminum split bushing then using Acra-glas to make the taper. If you've done a bit of machining you should be able to accomplish imstalling this barrel. Make sure you understand what you are trying to do and like everyone else said take your time.

I got a barrel vise. The bushing fit the barrel taper better than the one I made. It made taking off the barrel very easy. I noticed that running torque after breaking the barrel free was very much affected by the amount of torque I put on the action vice. Should I be screwing the receiver bolt through the vice and into the action and using a minimum of torque on the vise bolts in the future?

I am looking for the Brownell's article on rebarreling, but not able to find it yet.

I am also looking for a set of go, no-go gauges. MidwayUSA has the go gauge, but no one including Brownells, Midway, Graf's or Cabellas has the no-go gauge. Any suggestions? Thanks.

Ranb

Check Pacific Tool and Guage for the no-go, they have a website but I don't have it handy, it should come up on a search.

Why do you need a no-go? I've never used one.
Butch

Butch,
There are lots of ways of chambering a rifle. The way I was taught at gunsmithing school, was to cut the chamber until the go gage fits, then you must check with no go to see that you didnt cut the chamber too deep and create excessive headspace. I have heard that lots of old timers cut chambers just until it would chanber a round. Doesn't sound safe to me, but I tend to be very conservative when it comes to safety.
Steve

I've never understood the need for a no-go gage either. If headspace is set so that the bolt will just close on the go gage, then it's not needed. I personally set the headspace after the chamber is cut deep, by facing the shoulder to the correct length. As far as I'm concerned, it's a lot easier to cut .001" off the shoulder than it is to chamber another .001" deeper.

quote:

Originally posted by skb:
I have heard that lots of old timers cut chambers just until it would chanber a round. Doesn't sound safe to me, but I tend to be very conservative when it comes to safety.
Steve

Whats not safe about that? Isnt the object when setting headspace to keep the distance between the chambered round and bolt face to a minimum? What could be more minimum than cutting a chamber until the bolt just closed. Other than specifically going for a crush fit I mean. I think those old timers you heard about probably had it right. Or so I've heard.

quote:

Originally posted by Westpac:

quote:

Originally posted by skb:
I have heard that lots of old timers cut chambers just until it would chanber a round. Doesn't sound safe to me, but I tend to be very conservative when it comes to safety.
Steve

Whats not safe about that? Isnt the object when setting headspace to keep the distance between the chambered round and bolt face to a minimum? What could be more minimum than cutting a chamber until the bolt just closed. Other than specifically going for a crush fit I mean. I think those old timers you heard about probably had it right. Or so I've heard.

Sounds to me like you have not measured a few cases to see what a difference there is in the length of them, headspace wise.

The gauges are made to a standard. That is the correct word; standard. We have set up a standard so all is as close to one another as possible.

quote:

Originally posted by Jim Kobe:
Sounds to me like you have not measured a few cases to see what a difference there is in the length of them, headspace wise.

The gauges are made to a standard. That is the correct word; standard. We have set up a standard so all is as close to one another as possible.

How much of a variation are you talking about between cases? I'm not talking about belted case as they have their own special set of problems. I think that the old timers who know what they are doing can set headsapce within the "standard" parameters set forth by SAAMI without using a no-go gauge.

I contacted Pac-Nor about making the barrel to attach using a barrel nut in the same manner as the Savage rifles. They said they can do it, and supply a barrel nut that uses the Savage wrench.

However, they also said this method of attaching the barrel is not suitable for magnum cartridges.

Does anyone know why this is so? The Savage 110 is chambered for magnums, but not as large as the 338 RUM as far as I know.

Ranb

Ranb,

This is just a guess from some experiences my gunsmith buddy went through with several magnum Savages. (probably more like a dozen now)

He has been putting custom barrels on the large magnum actions in 300 and 338 RUM. He had the barrel come loose while testing several times and the nut broke on another gun while it was being tightened to prevent the problem.

It seems as though the torque of the larger bullets will loosen the barrel and the nut is just not enough to stop it.

He has since been building custom nuts that are strong enough to withstand the pressure that is needed to tighten them so they will hold.

This could be the reason, or I may be totally off. Thought I would mention it regardless.

Jim

In the case of the pre-threaded, pre-chambered barrel, things are what they are and you are assuming that Pac-Nor did a decent job of threading and chambering. This is a fairly safe assumption. Although most barrel makers don't obsess over straightness and concentricity the way one might think (they have too much experience and have learned what produces acceptable results in a reasonable time) they don't usually produce junk either.
For the fun of it, you can simply chuck that barrel in your 3 jaw chuck with the barrel through the spindle. If the muzzle end doesn't run out by more than .010" or so and the chamber end by more than .004"TIR, you can go ahead and cut the shoulder and it will be just fine. If you want, you can indicate the face of the shoulder with a .0001" dial guage before you cut. If it is within .0002", you are just fine. If the shoulder face is square but cutwhile the barrel is running a bit eccentric, it is still square and that is the only important thing as far as that particular cut is concerned. By indicating Pac-Nor's face, you know the threads are aligned though they may not be coaxial. They are perpendicular to the shoulder face since both the threads and shoulder were likey to have been cut with the same setup. Again, in this case, perpendicular is what matters,
If you want to lose more sleep over whether or not your recut shoulder will fit up well, you can carefully measure the thickness of the Remington recoil lug at 4 points. It's not unusual to see nearly .001" variation in thickness.
Agonizing over the perfect set-up is, perhaps, a good mental exercise but it doesn't get the job done and it is getting the job done that will make shooting your rifle possible!
BTW, there is nothing wrong with your plan to hold the barrel in the chuck and support the breech end on the tailstock center. Thousands and thousands of barrels have been fitted and chambered just that way and with good results. It will certainly work well for cutting a shoulder. The only thing I don't really like about it is that I don't like grabbing tapered pieces in my 3 jaw chuck. Hard on the jaws. Regards, Bill.

I finally got the barrel from Pac-Nor. It is a 30" stainless heavy palma with the last four inches machined to a diameter of .750" to mount a suppressor.

I mounted the muzzle end into the chuck and supported the chamber end with a steady rest. It took up most of the 31" of my lathe. Runout was within 0.0003" at the shoulder. Based on my measurements I only had to remove 5-10 thousands to get the right amount of headspace. After two cuts on the lathe, I ended up with 3 thousands headspace. I only had the GO gage to work with, so I used shims between the gage and the bolt face to determine the amount of headspace.

Once again thanks for the advice guys.

Ranb

I am in load development now. 105 grains of WC872 (20mm powder) highly compressed gave me about 2600 fps with 250 SMK, and very smokey. Way too slow; wished it worked as it is very cheap and very consistant.

4831 works much better, 87 grains gives about 3000 fps with a slight extractor mark but no flattened primer. Accuracy is 1/2 moa from a bipod. Very happy so far.

Ranb