Rebarreling my 788 Remington in 30-30, to 30-30 CBM-An adventure in Gunsmithing part 2

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GBertolet posted this 23 August 2019

I was gifted a 788 Remington in 30-30. It had lived a hard life, but was still mechanically sound. It spent much of it's life on the bayou. The stock was beat, and the metalwork exhibited some light rust, but the bore was not too bad. It needed an ejector, but still shot decently. The ejector was replaced, but boy this was an ugly rifle, and way too muzzle light for me.

I had read a post on the Cast Boolits forum, by a member, who designed a reamer for enhanced performance, with cast bullets in the 30-30. He named it the 30-30 CBM, as in Cast Bullet Match. It had tightened up dimensions with a gentler leade into the rifling. Manson made it for him, and has the drawing in his catalog, if anyone is interested.

As I mentioned in my last project, I got a bucket full of barrels with my lathe. Included was a 30 caliber 1-14 twist Douglass barrel blank. This one was cut off a both ends, deeply drilled and tapped for a scope block, and was 24.5 inches long. Looks like someone started a project, then abandoned it. I did some research on Greenhill's formula, and on an internet stability calculator, and learned that the 1-14 twist was fast enough to stabilize my 311291 bullet. A little iffy, but conditionally good. More on this later.

I took the plunge and ordered the reamer from Manson. Using a pin gauge, my bore diameter was .301, so Mr Manson said he would make me a .3005 live pilot. As this was considered a custom reamer, with a live pilot, the cost was $200, including a nice wooden storage box. Mr Manson promised a 5 month delivery, but I received it in less than 2 months.. Now the fun begins.

Getting the barrel off was an explicative laced exercise, with lot's of bad words spoken. That barrel just would not come off. I had the barrel so tight in the 12 ton hydraulic press, I could hear the wood blocks cracking, but just when I thought the barrel was ready to break loose from the receiver, the barrel would turn in the blocks. I tried one more thing. I put rubbing alcohol on a rag and wiped down the barrel. This time it cracked loose. Apparently there was still invisible oil in the pores of the metal, and the alcohol cleaned it out. I suspect there may have been sealant on the threads also. A lesson learned.

Being both ends of the barrel were cut, there was no chamber end designation, and I wanted to be sure of getting rid of the drilled scope block holes in the barrel, during the tapering process, without having to turn down the barrel more than I wanted to. I could wiggle a .301 gauge pin ever so slightly in one end of the barrel, so that looser end was to be my chamber. It worked out that the drilled holes could be gotten rid of, while maintaining the taper I wanted.

Next, lots of measuring here. Due to the limitations of my lathe's headstock, most work was to be done on centers, like the Ruger's were. I used the old barrel for a guide, for thread pitch, shoulder, and consideration for the recoil lug. I tried to do something a little different here. I planned to have the case headspace on the shoulder, rather than the rim. Probably a fool's errand, as after firing a case the first time, that is accomplished anyway. After alternating, touching up the barrel shoulder and chamber face, it looked like I was in the ballpark. My goal was .005 clearance between the rim and breechface. The finalization will be later.

Now the reaming begins. Run slow, cut a little at a time,clean the chips often, use lots of cutting oil, NEVER turn the reamer backwards, and finally, have the lathe stopped when inserting or removing the reamer, to avoid scoring the chamber walls by errant chips. One other thing, I inquired about purchasing a floating reamer holder. My mentor said no, I was to loosen the three bearings on the steadyrest, ever so slightly, after the reamer was started, with the lathe running. This would allow the pilot to find it's own center, eliminating the need of the floating reamer holder. Some may disagree with this method.

Now for the touching up of the chambering. I stripped the bolt, and screwed the receiver on the barrel, making it snug. I used a live factory round to set up the headspace. Not recommended, but I had no headspace gauge. The bolt was stripped anyway, so I felt secure. I was close on the initial reaming, but the bolt would not close. I put a dial indicator on the tailstock, reamed some more, and got things even closer. I put an extension on the reamer, and manually turned the reamer half a dozen turns, blew out the chips, and popped in the round again. Almost there. Measure twice, cut once, as Norm says. Repeated again, until the bolt closed with the slightest resistance. With the receiver removed I could just see daylight between the cartridge rim and the breachface. Close enough.

I did the same tapering treatment I did for the Ruger. Drawing out on a graph, the diameters by the inch, for the taper I wanted. On the metal lathe, I reduced the barel diameter in steps, to blend in later, using a disc grinder with a flap disc.. After a subsequent spin in the wood lathe, ( reasoning explained on my Ruger build post ), my blended taper was achieved. The already balanced faceplate and drive dog were made already, making the job a snap. I needed to do an extractor cut in the mill. Getting the clocking right was a little tedious, but it was completed with no blood loss. An 11 degree muzzle crown was also added.

The new barrel was as of a fatter taper than the factory one was, so I had to break out the barrel channel rasp, to fit the new barrel to the existing stock. With that together, i just had to shoot the darn thing.

I put on a heavy coat, welding gloves, and a machinist's face shield, and headed out back. This was August, not January. If anyone saw me, they would think I was nuts. I wasn't taking any chances. I must of looked like Neil Armstrong on a moon walk. Anyhow I fired two factory rounds into the berm, proofing it, without incident. The two cases extracted easily, and looked OK, so I was good to go. To date, they were the only jacketed bullets fired in this rifle.

I cold blued the barrel. It looks decent, but nothing spectacular. Next to replace that ugly stock.

I found a laminated stock at Boyd's that I liked. Nutmeg was the coloring pattern. It cost around $100, plus shipping. I learned that the 788's had several action screw spacings, dependent on caliber. I had to make sure I selected the correct one. The stock arrived in a week. The barrel channel was cut to the factory barrel dimensions, so a little rasping was in order for the replacement barrel to fit. With that done I noticed interference with the magazine. A little relieving there, resolved that issue. Things are starting to look up even more now.

I wanted to stamp the caliber designation on the barrel, but I didn't trust myself to get the stamping straight and presentable. I learned of a local business, that does laser engraving for trophies and plaques, who just started doing firearm engraving also. For $25, they laser engraved the caliber on the barrel while I waited. Looks nice.

I mounted a spare Leupold 10X silhouette scope, with a 1 min dot. A Weaver mount and rings came with the rifle, so I used them. I bought an extra magazine from Numrich. I thought I'd mention, that the 788's chambered in rimmed cartridges are unique, as they have two piece rotating bolt heads. This sort of makes these rifles special.

Now to load some ammo. I sized some once fired cases with my RCBS FL sizer die. Guess what, they won't quite chamber. Close, but no cigar. Turns out the factory ammo shoulder is set back a little more than my die allows for, and that's what I set the headspace by. Off to the bench grinder with the sizer die. After relieving a few thousandths off the bottom of the die, and readjusting, the shoulder is adequately set back now. After the cases are first time prepped, a Lee collet neck sizer works quite well. No more lubing mess. Lots of reloading with mid power loads, before FL sizing needed.

I have a lifetime supply of 4759, which I use in all of my other cast bullet rifles, 30 cal up to .458 with satisfactory results. This will be the powder I will use in in this rifle. I will start off with the 311291 bullet also. After initial testing I settled on 15.0 grains for a velocity of 1550 fps.

Groups of slightly over 1 inch, are common at 100 yards, with the 311291 bullet. Can't seem to do too much better. I do notice some occasional bullet tipping at that distance. Upping the velocity to boost the RPM's, or going to a shorter lighter bullet are my two options for the 1-14 twist barrel. I went with the shorter, lighter bullet, a Lee 309-150. Shoots pretty good with the same 15.0 gr 4759 load. More consistent than the 311291. Nice round groups. 10 shots, under an inch. This bullet seems better suited for the 1-14 twist barrel. Good enough for my needs.

I have been recently experimenting with powder coated bullets. I have not fired enough of them to say if they shoot better than the alox ones do. The bores are spotless and easy to clean. I learned that powder coating builds up the diameter of the bore riding nose of the bullet, often making chambering occasional rounds difficult, if not impossible. Inconsistent coating thickness is part of the problem. I tried making a bullet nose sizer for my Lyman sizer. I sizing up to the front driving band. It works, but the sized metal has no where to go, and leaves a bulge at the front driving band. Resizing the whole bullet gets rid of the bulge, but the bullet is apparently damaged, as they group poorly. I gave up on this idea.

The factory trigger was fair, but not great. I swapped out the trigger spring, which lightened it somewhat, but still not great at 3lbs with some creep. Brownell's had a sale on Timney triggers, so I purchased one. In attempting to install it, I noticed that the holes in the trigger block for the roll pin, which attaches to the receiver tang, were undersized. .090 is the size, by my pin gauge, and .096 was what I needed. I used a #41 drill in a pin vise to ream out the holes. No problem. I have read several reviews on this trigger, with several saying the hole was too small for them also, and had to be enlarged. Be very careful when driving in or out the roll pin. Be sure to support the receiver tang when pounding. The tang is small and if it breaks off, you are in deep do-do. Better have a TIG welder handy. The stock needed a little relieving for the safety to operate freely. Finally the bolt stop on the new trigger was too short. You could feel the bump on the rearward travel of the bolt. Not enough to stop it. If you were too energetic, the bolt would leave the receiver. A call to Timney had a longer bolt release on the way. While talking to the young lady at tech support, I mentioned the undersized roll pin hole in the trigger block. They were unaware of this. Apparently they don't read the reviews.

The new bolt stop arrived within a few days. It was .060 longer than the original. It was way too long. I could not even get the bolt in the rifle. Using trial and error, removing .030, while keeping the stop's contour, I was in business. It appears the underside of the bolt, that the stop contacts, was hammered over the years, which likely caused this issue.

I set the trigger to a nice safe 28 ounces. Nice and clean. Far better than the Remington factory trigger. Very pleased, might even be able to go lighter.

 

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GBertolet posted this 23 August 2019

The first post was too long for the allotted length, so this is part 2

The final specs on this rifle are 24 inch barrel, and with laminated stock and the big scope, weigh 10 1/4 lbs. Not exactly a walk around woods rifle. Total weight was a little heavier than I expected. A lighter scope might save 1/2 pound. Sometimes the rifle just lays there on target, other times it is a real struggle, with a big wobble area, while shooting offhand. I am not in the shape I used to be. This rifle was built to be a offhand shooter, not a bench gun.

I just added a 4 inch gong to my shooting range, to compliment the existing 6 and 8 inch gongs. The 4 incher will be a real test of my offhand shooting skill. Any misses will not be the rifles fault.

In summary, I am quite pleased, with the overall result of this project. Lot's learned, and experience gained. Currently, unless further load development is done, it will not win any CBA matches, but one inch groups at 100 yards, using unsorted or inspected bullets, and a dedicated powder, is not a bad start. Good enough for now!

I am sorry, I am long winded again. I hope all enjoyed it.

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jchiggins posted this 23 August 2019

Thank you for the post.  Although I lack a lathe and therefore the ability to do the kind of work you have done, I enjoyed reading about your project and approach to solving problems.  Well done and it looks like you have already achieved a great deal of success with the result.

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Ken Campbell Iowa posted this 23 August 2019

great post ... 

enjoyed your thoughts on reamer alignment ... i have followed for years the discussions on this subject ... 16 top precision gunsmiths have 16 different approaches to this.  all produce precision results.  

... and thanks for saving that 788 from terminal oxidation ... i have had several of these, in 243, 308, 44 mag. ... now down to just a nice 223 ... but got a lot of fun out of those " frugal " rifles.  

..in the event you get bored in a couple weeks, bet we could dream up another project for you ... don't hesitate to ask. 

ken

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mashburn posted this 24 August 2019

Hello GBertolet,

I enjoyed your article. I would like to add a statement. You were lucky that your headstock wasn't large enough in diameter to pass your barrel blank through. I do all of my barrel work between centers from the beginning of turning the outside to diameter. The bore is not concentric with the OD in most blanks. If your bore isn't concentric with the outside of the barrel and you run it through the headstock and dial indicate it the bore will not be concentric with the OD. It only takes a wee bit and you will have a egged chamber and probably the head of the case will not be backed up by the bolt face squarely & it will not shoot worth a crap When I had my shop open it was amazing how may rifles that I had come in done by supposedly  expert well known gunsmiths that were nothing but scrap iron.couple of examples: I had a 700 Remington come in that had been rebarreled by a supposed expert. , the threaded tang was about .050 off center. After he cut the tang and  and threads this far off how egged do you think the chamber was?The rifle had been turned into a peace of scrap iron. A friend  sent a model       52 Winchester and a high dollar barrel blank to another of these experts and when it came back guess what-it wouldn't shoot very well He sent it to me and I gave it a through exam. The first thing I caught was that when you ran a straight .22 caliber cleaning rod through the bore from the rear of the action and & down close to the muzzle the cleaning rod was touching the right side of the reciever at the back of the receiver What a goof up He had drilled and tapped the underneath of the rear of the receiver for another bedding screw The screw hole was no near the center of the receiver and with the screw in front of it pulling straight down and the newly installed one pulling to one side bedding with that screw was impossible.. No wonder it wouldn't shoot, The face of the bolt was only touching the case head a little bit just on the left  hand side. I get a kick out of the new rage of blue printing a rifle. They act like this is something new. Roy Dunlap did all of his rifles that way and so do I.

Keep up the good work and keep us informed. Sorry to sound like an old cranky fart but if it's worth doing it's worth doing right.

Mashburn

David Cogburn

David a. Cogburn

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SouthDakota4440 posted this 24 August 2019

Greetings GBertolet,

Great post....I too enjoyed reading your project article.  I always admire the kind of machining and problem solving ability you demonstrated....with the added bonus of restoring a neat old rifle. Great stuff!

Marc

mm

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mashburn posted this 25 August 2019

Hello GBertolet,

I meant no disrespect to you in my first response to your enjoyable post. I admire people like you who are interested and talented enough to build things. Over my time in working on and building rifles I've just gotten fed up with a lot of the gunsmiths out there and I know there are some great rifle smiths in business and I'm not talking about them. Most of the gunsmiths coming out of gunsmithing schools are just parts changers.

I hope you took no offense,

Mashburn

David a. Cogburn

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Ken Campbell Iowa posted this 25 August 2019

hey mashburn .. your comments about the bore vs. barrel od.  runout were right on, and important.  my favorite story is my 40x BR 22 rf match rifle from the custom shop at remington.  one land in the throat was about half reamed off ... i shot some groups just for fun, then set it back and rechambered .. cut the groups in half ...

ken

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GBertolet posted this 25 August 2019

 No offense taken Mashburn, I appreciate your comments. I was taught from the beginning, that whenever doing any barrel work, held in the lathe chuck, always indicate off the bore, never the barrel O.D., as the bore is seldom exactly centered in the barrel. Even with the best machinery, it is very difficult for the barrel maker, to drill a barrel exactly centered. I prefer use a tapered, expandable, bore sighting spud, placed in the bore to indicate off of, when using the chuck. Your post highlights that necessity. Thank you.

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mashburn posted this 26 August 2019

Hello again GBertolet,

I should keep my trap shut but you've probably already noticed that is hard for me to do. Most of the rifle barrels that I use, there are a few exceptions, are unturned blanks. I turn them like I want them and they are concentric. When you chamber through the headstock and have a collar of some sort to adjust that part of the barrel & you have the four jaw chuck putting pressure and when you use the the set screws on the outside fixture you have it also putting pressure and if the bore isn't concentric the chuck and the end fixture are putting pressure in different directions to locate the bore to zero runout. I have actually seen people use wood wedges driven between the barrel and the bore of the headstock to align the bore. As Forrest Gump says; ------ happens. I try to avoid anything that can loosen or go wrong somehow. Getting back to threading and chambering between centers, Here are some of my comments. First, make sure the tail stock center and the head stock centers are perfectly aligned. Second, after putting the barrel between centers make sure the back of the barrel where the steady rest will contact has zero runout. When I turn my own barrels I take care of this problem, but a lot of pre-turned blanks will not be machined that close. It's easy to take a few thousands off and make sure it is correct. After that you know it is running perfectly you can turn the tang and thread. After threading it is time to apply the steady rest. I agree with you about loosening the steady rest contacts up a wee bit. When I'm setting the rest up, I take a piece of household kitchen wrap and wrap it around the barre (one wrap) where the steady rest will contact and then run the contacts against the wrap. I lock the contacts and then squirt a little oil on the plastic  and turn the lathe on for a few seconds. This will tear the plastic apart and can be pulled out easily. That is how much clearance that I use and I do not have a floating reamer holder, I have a live center in the tail stock and put the hole in the back of the reamer on the center and use a small wrench to hold the back of the reamer. I've never egged a chamber or had a wobble that cut the back of the chamber oversize.

I'm not trying to steal your thread, I think you and I could be good friends if we lived close. What I'm trying to do is: I'm getting old and like to share the knowledge that I have acquired over the years to young people with a interest in guns and machining. Like Roy Dunlap said, I've built hundreds of rifles and enjoyed it all but now at my age I enjoy talking about guns, more  than building them.

I enjoyed your article and I hope it shoots wonderful forever.

Mashburn

David Cogburn

David a. Cogburn

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GBertolet posted this 26 August 2019

Mashburn, Thanks for the insight, I was taught that you can get a piece of 3/4" PVC pipe, or whatever size needed, slit it, and use it as an expandable collar at the rear of the headstock. This supports the back of the barrel, for better alignment in the lathe chuck, as you suggest. I think I would rather do that, than jam wood wedges in the headstock.

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shastaboat posted this 27 August 2019

Great post.  I used a ball point pen spring to alter my 788 trigger assembly on my .223 Rem 788.  You might try that on the factory trigger.

 

Because I said so!

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M3 Mitch posted this 28 August 2019

I doubt I will ever have the tools and knowledge to do a project like this, but it's interesting to read about and thanks to every one who posted on this.  Learn something every time I come on this site.

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