Author Topic: 45-70 chamber shim project  (Read 629 times)

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Offline 26-t

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45-70 chamber shim project
« on: December 14, 2009, 04:13:52 PM »
 Here is how the shim turned out. .016 thick 4140 chrome moly shim to take up the excess clearance in the over size chamber. I will glue it in the chamber as per Tim's advice ;). Thanks for the input ,this will get me going  ;D. 26-t

Offline quickdtoo

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Re: 45-70 chamber shim project
« Reply #1 on: December 14, 2009, 04:26:39 PM »
That's not what I meant, not that it shouldn't work tho.  ;)  The shim I did fits on the front side of the extractor post, it's just thick enough to sandwich between the post and the extractor notch and holds the rim out to zero headspace. I didn't want to make any changes to the barrel in case I had to send it back for repair, and the extractor could be replaced easily if it didn't work.

Tim
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Offline 26-t

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Re: 45-70 chamber shim project
« Reply #2 on: December 14, 2009, 04:37:31 PM »
This shim takes up the space in the rim groove. It is a snap it into the major diameter of the rim groove and brings the chamber back to zero headspace. That is how I envisioned the shim.  26-t

Offline peternap

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Re: 45-70 chamber shim project
« Reply #3 on: December 14, 2009, 04:53:52 PM »
Gotta admit it's a nice job and if I understand correctly, it' a spring fit so it can be removed. ;)
Use locktite so it will come out easily.

Offline 26-t

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Re: 45-70 chamber shim project
« Reply #4 on: December 14, 2009, 05:38:50 PM »
 ;D That is right ,Works so far,I will give a work out tomorrow and see if it stays put. 26-t

Offline 26-t

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Re: 45-70 chamber shim project
« Reply #5 on: December 15, 2009, 03:01:29 PM »
The glue failed >:(, tried an a different type of glue, it failed also. Back to the drawing board ???. 26-t

Offline peternap

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Re: 45-70 chamber shim project
« Reply #6 on: December 15, 2009, 03:15:08 PM »
The glue failed >:(, tried an a different type of glue, it failed also. Back to the drawing board ???. 26-t

You can use Tim's method which is the easy way out...or it looks like you enjoy a challenge. Make a doughnut cutter and cut something like poster board (I haven't mic'ed it but sounds about right). Glue the rings to the underside of your case rims ;D