Tenon Measurement to use for coned bolt action?Update***

[hoz53]

Hi All -- I am just wondering how to measure for tenon length on a cone bolt action?
Thank You

6/6/20 -- got my remington cone bolt tenon length checker made. found out my tenon for this one needs to be .900
thats including the recoil lug. .650 threaded in action and thats ok since there isnt much more thread than that in there. nice thing is this uses a 30 degree cone so i can use the checker for pandas to. mabie thats a reason to get one
thanks to all who helped out

 

[DaveTooley]

I always make the tenon length .010"-.025" shorter than the HS number. Depending on the action even more for cone breeches as the action threads may not be deep enough.

 

[Hal]

Kelbly has a post on their web site, on how to cut a tenon for their actions.

Hal

 

[Dusty Stevens]

If you have an old barrel you can use the woolums measuring tool from pma or make your own with a cone and dial indicator. You can make a tool with an old barrel stub to do the reverse on the action. Or you can use the method i posted on here crushing solder and creep up on it

 

[Tim Singleton]

You really need to make your own
It's a good practice job
Make a sleeve to slip over tenon that is .5 longer than tenon use with your go gauge for head space

Then make a Male 30d for panda and a Male 25d for bats
Use tools you made and a depth mic on the take off barrel

 

[hoz53]

Kelbly has a post on their web site, on how to cut a tenon for their actions.

Hal

thank you Hal - I will look that over.

 

[hoz53]

I always make the tenon length .010"-.025" shorter than the HS number. Depending on the action even more for cone breeches as the action threads may not be deep enough.

Ok Dave Thanks for that info.

 

[hoz53]

You really need to make your own
It's a good practice job
Make a sleeve to slip over tenon that is .5 longer than tenon use with your go gauge for head space

Then make a Male 30d for panda and a Male 25d for bats
Use tools you made and a depth mic on the take off barrel

Ok after looking at the pic, I see how that would work to measure from the back of the sleeve to the head space gauge for headspace-- Ok i edited my reply after i thought about it a minute. So to get tenion length i make a stub to thread in action with a cone in one end and measure that? Thanks a bunch for all the help youve given me

 

[hoz53]

If you have an old barrel you can use the woolums measuring tool from pma or make your own with a cone and dial indicator. You can make a tool with an old barrel stub to do the reverse on the action. Or you can use the method i posted on here crushing solder and creep up on it

Ok I think I understand all that. Thank You for the help
edit ok as ive been reading the replies here i think ive got a good grasp on this now. Ill make a trial on an old barrel stub and ill make it a little long so i can measure the gap and figure out tenon distance from that. thanks agin

 

[Roeder]

Ok after looking at the pic, I see how that would work to measure from the back of the sleeve to the head space gauge for headspace-- I dont understand how to get length of tenon from shoulder to breech face that i need to cut tenon before cone is cut. i dont get what " make a Male 25d means i guess. Thanks a bunch for all the help youve given me

Most of the popular custom actions do have a nominal or typical overall tenon length, such as 1.115 for Panda or 1.060 for BAT. Those dimensions are very close to the dimension from the front of the action to the bolt face, but that is not always the case. If you don't have a take off, you can start with that and cut the cone, checking for clearance before the cone gets all the way to the OD. The home made tools that I and others use engage somewhere on the surface of the cone and allow a comparative measurement from one barrel to another but do not necessarily bear any relationship to headspace or any drawing datum.

 

[jkohler]

Made this one. It’s a 1” gauge ball for measuring the cone depth and head space the other is a chunk of 12l14 that is ground 1” for Remington and others. The tool is bored 2” deep and 1.075 inside diameter. I used a starrett head

 

[hoz53]

Most of the popular custom actions do have a nominal or typical overall tenon length, such as 1.115 for Panda or 1.060 for BAT. Those dimensions are very close to the dimension from the front of the action to the bolt face, but that is not always the case. If you don't have a take off, you can start with that and cut the cone, checking for clearance before the cone gets all the way to the OD. The home made tools that I and others use engage somewhere on the surface of the cone and allow a comparative measurement from one barrel to another but do not necessarily bear any relationship to headspace or any drawing datum.

Ok that all clears alot up for me. I have a Rem 700 i got form PTG with a cone bolt in it they installed. Ive been thinking all along it will be a trial and error type deal and i see that appears to be true. That wont be to difficult. Ill call ptg and see if they will actually give me a dimension to start with. Thanks very Much

 

[hoz53]

View attachment 1182569 Made this one. It’s a 1” gauge ball for measuring the cone depth and head space the other is a chunk of 12l14 that is ground 1” for Remington and others. The tool is bored 2” deep and 1.075 inside diameter. I used a starrett head

Thats quite a tool. Ok i could see how it would measure the cone on an existing barrel then you could use it to check as your cutting another barrel and finally set the cone same as original barrel. did i miss anything? on the 1" cylinder you just use it to get a referance measurement from shoulder to breech way right? Thanks very much

 

[jkohler]

I use the 1” cylinder for checking head space and tenon length on Remington and others without a cone. I like using it more than a depth mic myself. It is worthless on a cone bolt unless you have a barrel to copy.

 

[hoz53]

I use the 1” cylinder for checking head space and tenon length on Remington and others without a cone. I like using it more than a dearth mic myself. It is worthless on a cone bolt unless you have a barrel to copy.

thats wat i thought-- thanks again

 

[Will Henry]

I simply measure with the depth gauge on my calipers down to the outside of the lug and cut the tenon to that length. I then cut the cone about halfway to depth. I put the bolt into the receiver in the locked position and screw the action on to the barrel until the bolt contacts the cone. I measure the gap between the receiver and barrel shoulder with a feeler gauge then cut the cone that much deeper plus .005". To measure the depth of cut, I set up a dial indicator to indicate the carriage movement. No trial and error, no special gauges, no fuss. WH

 

[Stumpy1]

When you guys cut for a coned bolt, do you cut a counterbore, or just run the cone into the chamber with no flat?

Why or why not? Trying to learn here.

Thanks!

Forgive the poor drawing...

Frank

 

[Dusty Stevens]

Ok that all clears alot up for me. I have a Rem 700 i got form PTG with a cone bolt in it they installed. Ive been thinking all along it will be a trial and error type deal and i see that appears to be true. That wont be to difficult. Ill call ptg and see if they will actually give me a dimension to start with. Thanks very Much

Just make an opposite cone that threads in the tenon, slides down and hits the cone and locks down. Then measure it with the pma woolums tool that jkohler posted. Keep it simple with no guessing

 

[Tim Singleton]

When you guys cut for a coned bolt, do you cut a counterbore, or just run the cone into the chamber with no flat?

Why or why not? Trying to learn here.

Thanks!

Forgive the poor drawing...

Frank

View attachment 1182603

There are no flat at the bottom of the cone on any actions I know
See attached 25d Bat and 30d Panda

 

[Dusty Stevens]

When you guys cut for a coned bolt, do you cut a counterbore, or just run the cone into the chamber with no flat?

Why or why not? Trying to learn here.

Thanks!

Forgive the poor drawing...

Frank

View attachment 1182603

Very few actions use that type cone. HS precision and one controlled feed defiance ive seen do. They are such a pain they are avoided for the most part