Tenon thread ranges.

[TAJ45]

A Bud is tooling up to do chamber work. I'm looking into possibly obtaining a set of pitch mics for tenon work. I see where 14-18 and 20-24 are std in the Starrett listings in the MSC catalog. They also list a 14 - 24 which I'm not too wild about.

Do the US actions, RugRemchestSav fall on both sides of the 1" for tenon OD? I'm pretty sure the Sav are coming in @ 1.06, but what about the Stolle, BAT, Lawton et al ?

Annnd what are the pitches on the above? Will a 16 - 20 tpi cover them all or do I need finer? I've used the three wire method as well as the wires system that fit over the anvils but pretty pricey but it would be pretty handy for a dedicated set or two of mics.

 

[shortgrass]

Threads on all of those are 1"+ . Save your money. As each receiver has minor variations in thread diameters, even within those of the same make, measuring as you are suggesting is not the way to get the proper fit. Turn the barrel tenon to the proper major diameter of the thread that's being used. After several pass, and it appears you're getting close to being done, start using the receiver, itself, as your gauge. Continue to make passes with the threading tool, checking after each pass, until the receiver will screw on to the barrel tenon without using a wrench or other mechanical assist, just by hand. It shouldn't just spin on , like a nut on a bolt, but you should feel a slight 'drag' in the thread as you turn it on by hand. After I'm there, I usually lay my 10" mill bastard on the threads just enough to "break the crest" on top of the thread. Clean it good, apply a little lube, and screw it on.

 

[Ggmac]

+1 shortgrass , I use anti sieze on the threads , use to use stp . Now with so much stainless ,anti sieze is just easier .
Forgot , I have been threading in reverse recently .

 

[dalewoolumjr.]

Well hard to do that on a glue in if you chamber through the headstock. And If you have customers order more than one barrel at a time, you have to have a way to measure the pitch. Keep records on action serial numbers with there measurements and never need to see the receiver again.

Dale

 

[TAJ45]

GgMac.......upside down and backwards eh? = I have been threading in reverse recently .

 

[Ggmac]

You know what I mean, if not it's not worth explaining .
We'll it does'nt mean I stand on the ceiling or the other side of the lathe .
Come on I was brought up around machine shop tooling , not this glorified type writer.
Thanks for catching it .
Best ,Gary

 

[TAJ45]

Easy Big Fella, I know what you mean......

 

[Ggmac]

I modified it after reading the post , I didn't mean it to sound like that.
Gary

 

[Ggmac]

Dale, it's not hard to measure and record your final cut . If in doubt you can use an old barrel stub and cut identical to the barrel , still using the receiver as a gauge . Once you get some of the commercial receivers with such large dif , you will see or come up with a solution easier than mine . And hope you share . Custom receivers are much more precise .
Gary.
Ps sometimes I cut a complete chamber and threads , give the customer the choice of keeping it or me holding on to it . If he keeps it I would charge a little ,as he would use it to set cartridge OAL gauge and be able to tell for sure how far his throat has moved . Some only keep vague round count records .
Gary

 

[TAJ45]

No heartburn here Gary.........

 

[shortgrass]

Well hard to do that on a glue in if you chamber through the headstock. And If you have customers order more than one barrel at a time, you have to have a way to measure the pitch. Keep records on action serial numbers with there measurements and never need to see the receiver again.

Dale

If he's just "tooling up" I seriously doubt that he's doing any glue ins! And who said anything about "thru the headstock"? Not the OP. Maybe he hadn't even thought of that and was planning on driving with the chuck and using the 'steady'. By the way, my short tutorial will work either way,,,,, thru the headstock or using the steady.

 

[Dusty Stevens]

my way to measure threads along with most chamberers is measuring over wires.

 

[shortgrass]

my way to measure threads along with most chamberers is measuring over wires.

And that method will give the best 'recordable' measurement.

 

[Concha]

my way to measure threads along with most chamberers is measuring over wires.

Yep.
If you do a lot of tenon on the same make you could manufacture gauges maybe 3 or 4 each one measuring .005 larger than the last. Use grease or 111 on the threads/wires to keep from droping them into the chip pan. I use a piece of cardboard underneath as well.

 

[Dusty Stevens]

I use the holder thats designed to hold the wires. Never have to touch em and keeps em seperated by pitch so youre not digging around for the right wires. Also you dont have to use grease and mess up your measurements and get everything nasty. Heres an example:

http://www.ring-plug-thread-gages.com/catalogs/thread_check/3wire_page2.htm

 

[Erik Cortina]

I use a .0001" screw thread micrometer.

 

[carlsbad]

Old school, I like the 3 wire method. Quick, easy, and cheap.

I like using a thread mic or a 3 wire because it tells you how close you're getting, allowing larger cuts without risking overshooting the mark. Also, on a stainless barrel it is good to have your final cut greater than .001" as some steels don't respond well to skim cuts.

--Jerry

 

[Shawnba67]

Watch eBay I picked up a starter 1-2" 16-20tpi micrometer for $35 it will do most of what's out there for what's left get a set of wires

 

[DaveTooley]

We use mics to measure to a tenth but thread mics aren't accurate enough to measure thread pitch. That doesn't make any sense. I use them every day on every barrel. Over all, in many ways much better than ring gages and much much easier than wires.

 

[bibsmachine]

We use mics to measure to a tenth but thread mics aren't accurate enough to measure thread pitch. That doesn't make any sense. I use them every day on every barrel. Over all, in many ways much better than ring gages and much much easier than wires.

I agree with Dave I have been using thread micrometers for 20 years and they work great when you are doing mail order barrels for custom actions.