Savage breech plug thread size

[cw]

Any one know the diam. and thread pitch for standard savage plug for 10ml-2 Is there a tap available?

[rossman40]

It is like 11/16X16 but it is not a standard spec. I have a 11/16X16 die and it is too tight for the breechplug.

[spoonover]

Can you tell what drill size 11/16 X16 tap takes? I have looked and came up with 5/8" , not sure if 50 or 75%

[Dave W]

IIRC the thread is 11/16X18. Edge can verify this.

[smokeless77]

For 11/16-24 thread they call for 21/32 drill @ 50%, thread, Probably close enough for 18 TPI.

John

[mountainam]

11/16x18 sounds like the Rem 700ML BP thr'd.

[Al]

I have one in my desk at work and will double check in the morning, but pretty sure it's 11/16-16.

The Remmy and Encore plugs are 11/16-20

Spoon, I'll have min's and max's for you too.

[Al]

confirmed, 11/16 x 16, pitch diameter is .640 (right at the low end of a class 2 thread)

Spoon, 5/8 hole gives a 75% thread

[spoonover]

Thanks, Pete's BP is 11/16X16 also. Have one of his BP's coming. I can get a bottom tap and drill bit on it's way to my place and start some testing. Have a junk Remington take-off to start on, wish me luck.

[edge]

Unless you need a very tight fitting thread, you can use this rule of thumb:

Subtract the thread Pitch from the Major diameter as your drill size.

So in this case 11/16 major diameter = 0.6875
Pitch = 1/16 = 0.0625

0.6875 - 0.0625 = 0.625 diameter drill.
In general it will yield about a 70% thread depending on how much oversize the actual hole size is.

edge.

[Al]

Feb 2, 2011 11:52:28 GMT -5 edge said:

Unless you need a very tight fitting thread, you can use this rule of thumb:

Subtract the thread Pitch from the Major diameter as your drill size.

So in this case 11/16 major diameter = 0.6875
Pitch = 1/16 = 0.0625

0.6875 - 0.0625 = 0.625 diameter drill.
In general it will yield about a 70% thread depending on how much oversize the actual hole size is.

edge.

was taught that about 29yrs ago!

[spoonover]

Thanks, that will be handy! 10X32 vent liner screw, how would you do this for drill size?

[smokeless77]

Here you go

www.shender4.com/thread_chart.htm

[spoonover]

Feb 3, 2011 8:05:49 GMT -5 smokeless77 said:

Here you go

www.shender4.com/thread_chart.htm

That is to easy, thanks, printer is going now!

[edge]

Number threads major diameter is calculated :

NUMBER x 0.013 + 0.060

#10 example = 10 x 0.013 = 0.130 + .060 = 0.190 diameter.

edge.

[joe21a]

I checked my tape and thread giude and it claims 11/16= 41/32 drill(.6406) for a 75% thread and a 21/64 drill (.6562) for a 50% thread. The 75% thread is usually used in alum. or brass

[edge]

Please double check those! They seem very large for an 11/16-16 thread.

edge.

Feb 3, 2011 10:46:22 GMT -5 joe21a said:

I checked my tape and thread giude and it claims 11/16= 41/32 drill(.6406) for a 75% thread and a 21/64 drill (.6562) for a 50% thread. The 75% thread is usually used in alum. or brass

[joe21a]

That is what it call for check the link above has same info

[edge]

NO!

That is for a 24 pitch thread and it is not the same!

If you use the machinists rule of thumb formula

A 24 pitch thread is 0.0417

0.6875 - 0.0417 = 0.6458

But we are using a 16 pitch tap or 0.0625

Here is a link that has our exact thread:

www.midstatesbolt.com/tap_drill_sizes.htm

edge.

[joe21a]

I never realized that the difference threads per inch made that much difference in the dia. That would account for some threads not being perfect over the years.

[edge]

Feb 4, 2011 18:23:44 GMT -5 joe21a said:

I never realized that the difference threads per inch made that much difference in the dia. That would account for some threads not being perfect over the years.

Many folks don't realize that.

Since most threads that we deal with are a 60 degree included angle they can be thought of as a series of the letter "W"

Since they are the same shape then the only way to have more or less threads is to make the "W" larger or smaller which in turn extends further into the hole ( low number of threads per inch ) or pulls it closer to the outside edge ( high number of TPI ).

That necessitates smaller or larger tap drills to keep the ratio proper.

edge.