.
Like a lot of the other kids I have given up Mickey Mousing action threads with single point cutting in favor of using taps. The theory of using taps is simple. A specially turned mandrel that matches the actions bore exactly is turned with a center on the nose that fits into the center drilled hole in the nose of the tap that the manufacturers use to cut and grind the tap. In essence, because you are screwing the action up over the non-turning tap, the tap becomes a single point cutter. Just like a boring bar with teeth on both sides so the thread is cut in perfect alignment to the centering mandrel.
Both the tap and the centering bar are held in close running ER collets which ensure alignment under .001 inch over 14 inches or so. Which of course is VERY close if you work it out over the 1 inch of action threads in the receiver. If you work out the numbers it is about .000071 inch of deflection per inch. Which is just as close but probably light years closer than one could ever hope to dial an action in too. Considering operator, machine, indicator bar and indicator error.
Initially I was going to buy the taps with the bar machined right into it. The main problem with this is that they simply cut the threads .010 over sized which in 98% of the cases is totally unnecessary. Most of the time only .0005 or .002 inch is all that is required to clean the threads up completely.
After talking to a few of my gun-plumber cronies I elected to just have the taps custom made in H4, H5, H6 and H7 sizes. Not cheap, but it allows me to work the threads up in .0005 inch increments.
The system works well and I was using an action wrench to screw the action up over the tap while it was in the machine. My only concern was that the pressure from the action wrench might be slightly oblonging the receiver threads because of the uneven pressure it placed on the receiver.
So, I finally broke down and made a close fitting collar that clamps over the receiver ring with even pressure to put my mind at ease. The collar seams to work just peachy and was turned from a chunk of 2-3/4 inch bar stock that I had in the scrap heap. The 3 cap screws are 5/16x24 TPI and time for the build was about 4 hours. I turn the collar with a simple crescent wrench. The whole venture was probably overkill but whatever. It's done.

Very neat........ You don't worry about your "centering bar" flexing?


.

.
I was initially. But then again PTG has been putting their brand on virtually the the same technology for some time now with no complaints.
What I didn't like about their system was, as mentioned, it cuts the threads .010 over sized all in one shot. That's a big jump. Lots of torque. I oped for this system because it lets you clean everything up in .0005 inch increments. That removes a lot of the cutting pressure. Plus, you can run the action up over the tap several times until it spins up cleanly. Then make the jump to the next .0005 inch over size.
I always had sort of the same flexing problems when re-cutting the threads with internal threading tools in the lathe. Because of the flex in the tooling and the double cats head I found that I had to make numerous clean up cuts to ensure that all of the flex had been worked out and everything was nuts on.
I also found that a lot of the time when I was done and rechecked my alignment with the mandrel, that something had shifted slightly in the cats head because of the cutting force and things were out of whack. That's not an uplifting experience at all!
This system seems to be a whole lot more idiot proof than cutting them in the lathe with a single point cutter. And idiots like me need all the help they can get.

The down side is, it's a very expensive way of going about it. I have $900 invested into it just with the taps alone and also a lot of time invested in different sized mandrels and other Mickey Mouse tooling I've made. Granted, I have a Cuttermaster Tool and Cutter grinder so I can resharpen the taps virtually forever. But for the guy that does one or two per year, it's not the way to go.

Thank you very much for your explanation Sir. Makes very good sense.

I really appreciate you posting these projects I sure learn a lot from them.


.

Have you ever done any of this kind of work on surplus military Mauser actions?

How about Winchester Model 70 actions?

I have re-cut the threads and trued up a few model 70s and the odd Sako. It really makes no difference what type of action you select. The operations involved in truing them up are exactly the same from one to the next. But I do think that it is largely a wasted effort in a hunting rifle.
Of course there are proponents on either side of the fence that will fight to their dieing breath for what they believe in, but it's a lot like religion. You have to take a leap of faith because one has ever been able to sit down and prove that the theory of having everything perfectly aligned, really does give you anything more in the way of accuracy.
It is a good theory and in principal it makes sense, but the returns (if they really exist) are so very small that its hard to justify the $800 that some of these clowns are charging to do it. Especially in an action that was designed to make 3/4 inch groups and go up mountains and flail lead at sheep.
Personally I believe that the technology might have some benefit to the bench rest crowd and might give them a few thousandths of an inch when the smoke clears. But as far as the hunting crowd, it's not something that I openly sell. I am however, a whore and I will do damned near anything for money, just like everyone else. Because of that I have trued up quite a few hunting actions at the customers request. But I do let the customers know what I think and let them make their own decisions. After all, it's not my zoo and they aren't my monkeys. I'm just the clown that they are employing to do the work.

This is a great line. It describes my work place. " After all, it's not my zoo and they aren't my monkeys. I'm just the clown that they are employing to do the work." Thank you so much.

Speerchucker, i'm so glad you're on here, top gunsmith and wordsmith.

quote:

Originally posted by speerchucker30x378:
I have re-cut the threads and trued up a few model 70s and the odd Sako. It really makes no difference what type of action you select. The operations involved in truing them up are exactly the same from one to the next. But I do think that it is largely a wasted effort in a hunting rifle.
Of course there are proponents on either side of the fence that will fight to their dieing breath for what they believe in, but it's a lot like religion. You have to take a leap of faith because one has ever been able to sit down and prove that the theory of having everything perfectly aligned, really does give you anything more in the way of accuracy.
It is a good theory and in principal it makes sense, but the returns (if they really exist) are so very small that its hard to justify the $800 that some of these clowns are charging to do it. Especially in an action that was designed to make 3/4 inch groups and go up mountains and flail lead at sheep.
Personally I believe that the technology might have some benefit to the bench rest crowd and might give them a few thousandths of an inch when the smoke clears. But as far as the hunting crowd, it's not something that I openly sell. I am however, a whore and I will do damned near anything for money, just like everyone else. Because of that I have trued up quite a few hunting actions at the customers request. But I do let the customers know what I think and let them make their own decisions. After all, it's not my zoo and they aren't my monkeys. I'm just the clown that they are employing to do the work.

How refreshing!

quote:

Originally posted by lindy2:
Have you ever done any of this kind of work on surplus military Mauser actions?

How about Winchester Model 70 actions?

DON'T FEED THE TROLLS

quote:

Originally posted by dpcd:
It would be useless waste of money to buy the tooling to cut Mauser threads as I don't think there is any benefit to re-cutting them anyway. But, some customers have more money than sense so it might be a way to make some money. I had a guy two weeks ago who wanted me to "true" up his Mauser front ring. I did, but I also told him that I fit barrels to torque on the inner ring and just touch the front ring. He didn't understand the concept, and paid the price.

Yup, you hit the nail right on the head. And if some guy just HAS to have it done they can always be single pointed. Either system works just as well as the other but single pointing requires no proprietary tooling.

I have seen some guys true up the face on Mausers and use the face as the crush surface. I generally use the back ring because using the face, with such a course thread tends to give uneven support where the thread begins on the face.

I guess it's really one of those hypothetical thingys because there is support on all sides. It's simply more bearing surface on one side than the other and my little pointed head does handstands when I look at it.

Nit picky, fussy, anal retentive, over thinking idiot that I am. Some days I start to think I'm stupid enough to have been an engineer. I'll catch hell for that one.

Rod,
I've enjoyed your post for the last few years. You do know of what you are talking about. I'm glad you found your way to this forum.

quote:

Originally posted by butchlambert:
Rod,
I've enjoyed your post for the last few years. You do know of what you are talking about. I'm glad you found your way to this forum.

I've stolen quite a few little gems off of you too Butch. Part of the reason I stopped in here again because I saw that you were posting here. Like everyone else I'm not so much here to give stuff, but more to swipe little tidbits when no one is looking. And I do !

I still remember back in the day when I had a library of over 1000 gunsnithing related books. I actually sold all of my books and now I just use the internet. In fact I use my fool smart phone more than anything. The reason being is that it's always laying on my bench and the search feature is all voice. No hunting and pecking for schematics. I also use it as a camera and snap pictures of some of the mouse traps I get as I take them apart so that I don't get lost on the return trip. Without a word of a lie I drain the batteries on the fool thing by 1:00 every afternoon and have to plug it in for 20 minutes so that it's good for another 5 hours.

I did finally break down and buy a Samsung G3 a year ago. Bigger looker-screen and the voice recognition is light years ahead of the IPhone 5 I had. I have been putting it off, but I will eventually buy a tablet for looking up schematics and parts lists. I hate to have to admit it, but the internet makes knowledge gathering so simple and efficient that I can't live without it now. Whoever thought that it could ever be good for anything but downloading porn and rock & roll huh?

I like the idea of the minimal cuts with the tap. The collar to fit over the receiver ring is also a good idea and is something I always did when using the jig with the four set screws so as to minimize distortion of the ring.
The only hunting actions I re-cut any more are the post-64 Model 70's. I take them out to 1 1/16 just to end up with a full thread and avoid distortion of the chamber when the barrel is torqued up.
Of course, now that I'm retired, I only do my own stuff and the Model 70's are all done. I might as well toss the fixtures! Regards, Bill

quote:

Originally posted by Bill Leeper:
I like the idea of the minimal cuts with the tap. The collar to fit over the receiver ring is also a good idea and is something I always did when using the jig with the four set screws so as to minimize distortion of the ring.
The only hunting actions I re-cut any more are the post-64 Model 70's. I take them out to 1 1/16 just to end up with a full thread and avoid distortion of the chamber when the barrel is torqued up.
Of course, now that I'm retired, I only do my own stuff and the Model 70's are all done. I might as well toss the fixtures! Regards, Bill

Hey there Billy? Last time I spoke with you on the phone you said you had some posh job working for the BC government and were living out in gods country by Fernie. Did you retire from that too? Or are you just referring to building guns for whiny people with no money? LOL

The closest I cam to working for the government was a year spent on a bridge building project as a laborer! The only other gainful employment has been as a machinist in a hydraulics shop and, of course, the aformentioned gunsmithing. The next step is, I suppose, a stint as a Wal-Mart greeter!
I have enough projects of my own to keep me satisfied as far as gun building is concerned. I have a lot of hunting, fishing, and motorcycling which has to get done over the next ten years or so. We are still in the Kootenays and have a small campground with a waiting list for retirement income. Of course, since I'm a certified old guy, the governement just throws money at me!
Unlike you, I get very little information from the internet and have carefully avoided accumulating too much knowledge. I figure, given my limited capacity, I shouldn't try to overload the old cortex so as to avoid any sort of blowout!
I have to say, in spite of the ready availability of good precision actions, it's more gratifying to re-work production actions; as long as you don't have to earn a living at it. Also, I feel like I really should be able to get a 700 to shoot right along with the custom actions but sadly, at the I'm not sure this is the case. If I was as serious about trying to win as I was as a young guy, I wouldn't mess around with the old stuff at all.
For hunting, I'm pretty solidly in the "if it's a repeater, it should be a Mauser" camp although I will use a Winchester if I must. Regards, Bill.

quote:

Originally posted by Bill Leeper:
The closest I cam to working for the government was a year spent on a bridge building project as a laborer! The only other gainful employment has been as a machinist in a hydraulics shop and, of course, the aformentioned gunsmithing. The next step is, I suppose, a stint as a Wal-Mart greeter!
I have enough projects of my own to keep me satisfied as far as gun building is concerned. I have a lot of hunting, fishing, and motorcycling which has to get done over the next ten years or so. We are still in the Kootenays and have a small campground with a waiting list for retirement income. Of course, since I'm a certified old guy, the governement just throws money at me!
Unlike you, I get very little information from the internet and have carefully avoided accumulating too much knowledge. I figure, given my limited capacity, I shouldn't try to overload the old cortex so as to avoid any sort of blowout!
I have to say, in spite of the ready availability of good precision actions, it's more gratifying to re-work production actions; as long as you don't have to earn a living at it. Also, I feel like I really should be able to get a 700 to shoot right along with the custom actions but sadly, at the I'm not sure this is the case. If I was as serious about trying to win as I was as a young guy, I wouldn't mess around with the old stuff at all.
For hunting, I'm pretty solidly in the "if it's a repeater, it should be a Mauser" camp although I will use a Winchester if I must. Regards, Bill.

LOL
The way the gubberment is going I don't think I will ever get an Ole Peckerheads pension! I started another shop in Edmonton 5 years ago. Just gunsmithing and machining, no sales and NO MORE WARRANTY WORK! I'm currently looking for more space so I can add some machines. I don't think I will ever retire though. A lot of my friends have, but I think I would go out of my little, freaking, pointed head if I ever did.

I'm actually the last gunplumber in Edmonton and I think I'm the last fully trained one in Alberta. Everyone else went belly up or moved on to paying work. Little Paul Lefaive was the only other guy who tried to stick it out and he died of cancer about 6 or 7 years back.

I spoke with Ronnie Zinkhan on the phone about a year ago. I think you worked with him at Gun Craft. He's semie retired and doing well in Saskatchewan. He remarried a few years back. He's getting kind of dotty though and you have to give him a bit of time for his brain to switch gears and catch up to what you are saying.

Nice to here you're doing good Billy. But I'd give up on the Walmart Greeter idea. I hate to have to break the news to you, but like me, you're a bit to grumpy for that vocation. LMAO

Rod Henrickson

Very ingenious. Is this method applicable only to truing/chasing or can it be applied to new threading? Can it work with dies as well (ie. threading barrels)?

quote:

Originally posted by speerchucker30x378:
.
Like a lot of the other kids I have given up Mickey Mousing action threads with single point cutting in favor of using taps. The theory of using taps is simple. A specially turned mandrel that matches the actions bore exactly is turned with a center on the nose that fits into the center drilled hole in the nose of the tap that the manufacturers use to cut and grind the tap. In essence, because you are screwing the action up over the non-turning tap, the tap becomes a single point cutter. Just like a boring bar with teeth on both sides so the thread is cut in perfect alignment to the centering mandrel.
Both the tap and the centering bar are held in close running ER collets which ensure alignment under .001 inch over 14 inches or so. Which of course is VERY close if you work it out over the 1 inch of action threads in the receiver. If you work out the numbers it is about .000071 inch of deflection per inch. Which is just as close but probably light years closer than one could ever hope to dial an action in too. Considering operator, machine, indicator bar and indicator error.
Initially I was going to buy the taps with the bar machined right into it. The main problem with this is that they simply cut the threads .010 over sized which in 98% of the cases is totally unnecessary. Most of the time only .0005 or .002 inch is all that is required to clean the threads up completely.
After talking to a few of my gun-plumber cronies I elected to just have the taps custom made in H4, H5, H6 and H7 sizes. Not cheap, but it allows me to work the threads up in .0005 inch increments.
The system works well and I was using an action wrench to screw the action up over the tap while it was in the machine. My only concern was that the pressure from the action wrench might be slightly oblonging the receiver threads because of the uneven pressure it placed on the receiver.
So, I finally broke down and made a close fitting collar that clamps over the receiver ring with even pressure to put my mind at ease. The collar seams to work just peachy and was turned from a chunk of 2-3/4 inch bar stock that I had in the scrap heap. The 3 cap screws are 5/16x24 TPI and time for the build was about 4 hours. I turn the collar with a simple crescent wrench. The whole venture was probably overkill but whatever. It's done.

[QUOTE]Originally posted by Bobster:
Very ingenious. Is this method applicable only to truing/chasing or can it be applied to new threading? Can it work with dies as well (ie. threading barrels)?

Barrel threads should always be single point cut between centers to preserve alignment with the bore. Howa did manage to come up with a way to interpolate the barrel threads on the Mark V, but that was also done between centers in a CNC.

Action threads are also best single cut, but for production, a lot of companies do ridged tap them. Ridged tapping requires some pretty heavy equipment to do with any accuracy.

On threads that large, taps only work well for cleaning up, when most of the thread is already cut. To try ridged tapping 1-1/16x16 in the lathe would stall out equipment used by gunsmiths and the threads wouldn't come out straight. I do ridged tap all the threads for my muzzle brakes in conventional gunsmith sized lathes and they come out within .001 at 1.5 inches. The largest thread I generally cut that way is 5/8 x 28 and that's only a .027 cut. I have also ridged tapped 5/8 x 24 with no problems but I think that's pushing the limits of small machines.

Thank you for the education. Back when I was 15 yrs old I worked at a wire rope and chain shop making logging equipment. The owner, Bill Rochester, had invented a device called a "screw-on ferrule". This allowed loggers to rig chokers in the field without sending back all of the hooks. The process involve swageing a steel sleeve onto the end of the wire rope choker. Then placing it in a Ridge machine to thread it. A threaded ferrule was made to complete the package. Kinda brings back memories.

When Shilen introduced their DGA action, back in the mid-seventies, they cut the action threads with an unpiloted tap. Ed Shilen said it cut to center well enough for the purpose. The DGA actions I bought in the late-seventies seemed to contradict this claim though and were the most crooked receivers with which I ever worked until I bought some MRC's thirty years later.
I don't believe the tapping was the real culprit though. I suspect it was a cumulative error from inproper fixturing. If the bore is crooked, the tap will run in crooked so Ed Shilen was right. The tap did cut to center well enough but the center was wonky. Those DGA actions were the first actions where I felt the need to rethread. To illustrate how bad they were, I installed the barrel on the first one (which was to be my new Heavy Varmint rifle) the night I took it out of the box. When I screwed the barrel in, it didn't come up solid but felt spongy. I looked closely and the barrel shoulder was only hitting on one side. Using a feeler gauge, I found the other side had a gap of .006". I turned a close fitting mandrel from an old barrel and slid it into the receiver. When I looked through the mandrel, I could not see through the barrel. I returned this action and the replacement was much better though still not straight. To re-cut these threads, I epoxied a sleeve on the receiver ring then mounted the recever on the madrel and set it up between centers. I turned the outside of the sleeve true. I then pushed the mandrel back enough that I could access the threads, grabbed it in the four jaw chuck, and ran the sleeve in the steady while facing the receiver and chasing the threads. Afterward, it was a simple (?) matter to heat the sleeve and clean off the epoxy. Maybe not the most elegant way of doing things but it worked out OK.
I believe Wichita used a piloted tap to thread their receivers and they were quite straight. I know I had much better success when I switched to their actions!
Shilen must have made some good ones though. In 1978, I think it was, Bob Forslund demonstrated the best shooting HV rifle I had seen and it was based on a DGA action. Luck of the draw, I guess.
It is possible to mill threads as well and this is done on some receivers today. I believe the MRC receiver were done this way. They were crooked but not because of any failing within the milling process but from poor fixturing and warpage during heat treat. Regards, Bill

I don't remember the whole story on those DGA actions but it seems to me Ed made them after his split with that musician fellow. I think the first ones were turned out in a friends machine shop or gunshop. I had heard from Al Murdoc that the first ones were pretty crude. If memory serves the later ones were investment cast and then cleaned up. I had one of those actions for many years that I used for shooting gophers. Harvey Astley of Brooks eventually got that, my Hall and Swindlehurst action.

The first actions from Shilen (SS&D)were a true custom and were a machined action. The DGA actions were investment cast and were an attractive action, if nothing else.
After truing, my DGA was OK but I never could get to like it. I won some matches with that rifle but it was always a struggle. If I was serious about a match, I left it at home. Regards, Bill

What collet holder is that? Looking for one and I do not like the draw bar type.

quote:

Originally posted by WoodHunter:
What collet holder is that? Looking for one and I do not like the draw bar type.

It's an ER40. They seem to run about.005 inch at 4 inches lineally and .001 inch axially at the nose on good clean cold roll and a bit closer on ground stock. I started using them for making brakes because they run so well lineally. I went from a 3 jaw to a 5C collet system. On cold roll the three jaw was running out about .020 at 4 inches and about .002 axially.

The Bison 5C chuck ran about .010 at 4 inches and about .0015 inch axially at the nose because they are only nose closers. Not to bad but drilling the brakes with all the holes in them allowed chips to migrate up into the collet and it took 5 minutes to back the collet out from the chuck and clean it. I see now that the Asians have started making knockoffs of the Bison for less than half the price. I have never used one so I can't vouch for the quality.

I then went to a thru type, 5C draw bar system. That worked a lot better. It had the same run out, but it allowed me to get the collets a lot tighter and it only took a minute to spin them out and clear them.


I finally went to the ER40s after using them in a machine shop on a CNC. The ER40s seem to be the end all, At least for me. They hold a lot tighter and run a lot closer than the 5C collets. Spinning them out and cleaning them only takes 30 seconds. They are also a lot cheaper that a 5C Bison.

Tools4Cheap used to sell them but I emailed Jeff the other day about getting a couple more to use for work holding on the mill and he said he had none on order. I ordered a couple more from ARC. I have bought stuff from them before and their prices and shipping are good. Just not as quick as Jeff.

http://www.arceurotrade.co.uk/...-Lathe-Collet-Chucks