The Firing Line Forums

Go Back   The Firing Line Forums > Hogan's Alley > Handguns: The Revolver Forum

Reply
 
Thread Tools
Old January 14, 2013, 12:38 AM   #1
bspillman
Senior Member
 
Join Date: October 28, 2011
Posts: 228
End Shake

Hey folks i just bought a vintage charter arms under cover, stamped bridgeport conn. the gun locks up tight side to side but could have some endshake. can anyone tell me what the measurements should be to be at factory condition? Also what should the measurement be between barrel and cylander. Right now the cylander slightly touches the barrel when i open and close it.
bspillman is offline  
Old January 14, 2013, 09:24 AM   #2
kraigwy
Senior Member
 
Join Date: June 16, 2008
Location: Wyoming
Posts: 9,208
I wouldn't worry about what the "factory" says end shake should be, I'd worry about what YOUR gun says it should be.

I know, at first that doesn't make since, but it does.

There are two things we need to worry about when it comes to what we call end shake. End shake is basically how much the cylinder slides back and forth when the cylinder is closed.

It can mean, that when the cylinder is slid to the rear, you have too much gap between the cylinder and the forcing cone (rear of the barrel). This allows too much gas to escape out the side instead of pushing the bullet out the barrel which means you'll loose a bit of velocity.

Then we have the possible problem of too much gap when the cylinder is allowed move too far toward the barrel. These could mean the firing pin cant reach the primer, or not hitting the primer hard enough to get it to go off.

To me, this is much more critical then excessive cylinder gap. A round not going off is much more critical then a bit of gas escaping.

If you loose velocity do to excessive cylinder gap, you can load a bit hotter or find a hotter round to make up for that velocity loss.

If the firing pin doesn't get the primer to go off firing the gun, it could be life threatening.

Even if the cylinder is slid back, the energy used by the hammer may be used to push the cylinder forward instead of setting off the primer.

Factory can give you a certain number but that number wont take into consideration of the wear of the revolver. Only you (or your gunsmith) can tell whats needed for your gun.

Brownell, Midway, and other gunsmith suppliers sell shims to fix either problem. They come in sets of shims about .002 thick. Depending on your problem, you need the shims that go on the yoke, forcing the cylinder to stay at the rear of the gun. When you add these ships or bushings (what ever you want to call them) you want to check to make sure to don't put too many in. Load the cylinder with EMPTY cases to make sure your cylinder rotates freely.

Same with cylinder gap, be careful not to add too many shims where there is drag between the cylinder and forcing cone. You want to check this with a dirty, warm gun. You fix the gap with a clean cool gun, it may work, but then will jam up when the gun gets dirty and expands do to heat with extensive shooting.

Hopefully, If I didn't answer your question, I at least didn't confuse you too much.
__________________
Kraig Stuart
CPT USAR Ret
USAMU Sniper School Oct '78
Distinguished Rifle Badge 1071
kraigwy is offline  
Old January 14, 2013, 09:54 AM   #3
Two Old Dogs
Member
 
Join Date: November 28, 2012
Location: Eastern SC
Posts: 68
My first question is: is the gun clean? Carbon and powder residue buildup on the cylinder face and the rear of the barrel can reduce the cylinder/barrel clearance. Since your cylinder slightly touches the end of the barrel, a good cleaning may open the gap between the cylinder and barrel. Normally, the gap between the cylider and barrel should be in the 0.003" to 0.006" range and can be measured with a feeler gauge.

If your cylinder will move back and forth with the cylinder closed, you do have end play and a repair, possibly with shims as susggested above, may be in order. Also you should check to insure that the crane is not bent, which can cause misallignment of the clylinder and rubbing of the face of the clylinder on the rear of the barrel.
Two Old Dogs is offline  
Old January 14, 2013, 07:05 PM   #4
crawdad185
Member
 
Join Date: October 29, 2008
Location: GA
Posts: 20
Just curious, how do you check the crane to insure it is not bent? Should you be able to look at it and tell?
crawdad185 is offline  
Old January 14, 2013, 08:25 PM   #5
kraigwy
Senior Member
 
Join Date: June 16, 2008
Location: Wyoming
Posts: 9,208
A quick check would be to close the cylinder and check for a gap of the frame of the revolver.

A more accurate measurement or how much, would be made using a dial indicator.
__________________
Kraig Stuart
CPT USAR Ret
USAMU Sniper School Oct '78
Distinguished Rifle Badge 1071
kraigwy is offline  
Reply

Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -5. The time now is 01:16 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
This site and contents, including all posts, Copyright © 1998-2013 S.W.A.T. Magazine
Copyright Complaints: Please direct DMCA Takedown Notices to the registered agent: thefiringline.com
Contact Us
Page generated in 0.07194 seconds with 9 queries