« previous next »
Pages: [1]   Go Down

Author Topic: headspace for a .45-70  (Read 1157 times)

0 Members and 1 Guest are viewing this topic.

Offline mcgrow

  • Trade Count: (0)
  • Member
  • *
  • Posts: 9
  • Gender: Male
headspace for a .45-70
« on: December 16, 2009, 12:35:10 PM »
Hello
I need help with the headspace of a Remington Rolling Block in .45-70.
Do you have the measure of the GO and NO-GO gauges?. Can be the rim plus .005" ?
A total .075"  for the go gauge and .078" for the NOGO. Is correct my way of thinking?
Thanks in advance
McGrow
Logged

Offline John Traveler

  • Trade Count: (0)
  • Senior Member
  • *****
  • Posts: 1359
Re: headspace for a .45-70
« Reply #1 on: December 16, 2009, 04:33:55 PM »
Rim thickness + 0.006" should be the maximum headspace dimension.

To check this, you can use an automotive feeler gauge with factory cartridge cases.

The breech block should close and lock using no more than a 0.006" leaf.

Anything thicker is excessive.
Logged
John Traveler

Offline trotterlg

  • GBO Supporter
  • Trade Count: (36)
  • Senior Member
  • *****
  • Posts: 3978
  • Gender: Male
Re: headspace for a .45-70
« Reply #2 on: December 16, 2009, 06:17:35 PM »
I can say that I have never seen brass with SAAMI maximum rim thickness.  If you go with SAAMI specs plus some you will end up with excessive head space for shure.  Larry
Logged
A gun is just like a parachute, if you ever really need one, nothing else will do.

Offline mcgrow

  • Trade Count: (0)
  • Member
  • *
  • Posts: 9
  • Gender: Male
Re: headspace for a .45-70
« Reply #3 on: December 17, 2009, 12:04:05 PM »
Thanks for your answers
I agree with you that the factory shells don't have usually the SAAMI specification. But then,which is the specification for the gauge or GO and NO-GO? Been the cartridge plus a shim a way of determine the headspace for a particular cartridge, with which make of cartridge the error is minimum?
Can you help me with the SAAMI specification for a .45-70 chamber dimensions?
Thanks again and best wishes for you
Logged

Offline gunnut69

  • Moderators
  • Trade Count: (0)
  • Senior Member
  • *****
  • Posts: 5005
Re: headspace for a .45-70
« Reply #4 on: December 17, 2009, 01:20:41 PM »
I don't have a guage to look at and don't have a listing of the demensions. A cartridge with shimms is a poor way to set headspace dimensions.
Logged
gunnut69--
The 2nd amendment to the constitution of the United States of America-
"A well regulated militia, being necessary to the security of a free state, the right of the people to keep and bear arms, shall not be infringed."

Offline trotterlg

  • GBO Supporter
  • Trade Count: (36)
  • Senior Member
  • *****
  • Posts: 3978
  • Gender: Male
Re: headspace for a .45-70
« Reply #5 on: December 17, 2009, 05:56:09 PM »
The chamber dimensions will have zero to do with the headspace you set, it is done on rim thickness alone.  This is one case where a cartridge plus shims is the perfect way to measure what you have or use it to set up what you want.  Larry
Logged
A gun is just like a parachute, if you ever really need one, nothing else will do.

Offline mcgrow

  • Trade Count: (0)
  • Member
  • *
  • Posts: 9
  • Gender: Male
Re: headspace for a .45-70
« Reply #6 on: December 17, 2009, 11:45:23 PM »
Larry: I need to chek the headspace on a Remington Rolling block. With cases and shims it closes with a .0075". But I don't know if the cases has the right rim dimension.
When I ask for cartridge dimensions, I try to ask for the rim thickness.
Sorry for my english writing.
Thanks, best regards
Gus
Logged

Offline trotterlg

  • GBO Supporter
  • Trade Count: (36)
  • Senior Member
  • *****
  • Posts: 3978
  • Gender: Male
Re: headspace for a .45-70
« Reply #7 on: December 18, 2009, 09:53:56 AM »
Try closing it with .010 inch shim, like I said, you will never find factory brass with maximum SAAMI rims.  Larry
Logged
A gun is just like a parachute, if you ever really need one, nothing else will do.

Offline Headache

  • Trade Count: (0)
  • Member
  • *
  • Posts: 32
Re: headspace for a .45-70
« Reply #8 on: December 21, 2009, 08:54:08 AM »
mcgrow,

The SAAMI headspace for the 45-70 is .070" MIN to .077" MAX.

Headache
Logged

Offline trotterlg

  • GBO Supporter
  • Trade Count: (36)
  • Senior Member
  • *****
  • Posts: 3978
  • Gender: Male
Re: headspace for a .45-70
« Reply #9 on: December 21, 2009, 07:07:43 PM »
Headache:  I doubt that, that may be the rim thickness, but for sure not the head space.  Larry
Logged
A gun is just like a parachute, if you ever really need one, nothing else will do.

Offline mcgrow

  • Trade Count: (0)
  • Member
  • *
  • Posts: 9
  • Gender: Male
Re: headspace for a .45-70
« Reply #10 on: December 22, 2009, 01:30:29 AM »
Thank you Headache!!
I'm going to make the gauges in that dimensions and chek it.
Season greetings
mcgrow
Logged
Pages: [1]   Go Up
« previous next »