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Rick H.
January 29, 2009, 09:52 PM
Hi All: I have an 1873 Uberti lever gun in .357 caliber. Whenever I fire .357 ammo thru it the little tab on the bottom of the bolt face breaks off. I have sent it to the gunsmith I bought it from a couple of times now and he replaces the bolt and sends it back to me. I take it to the range and put one or two .357 rounds thru it and off goes the little tab. Tonight I decided to take a closer look at the rifle and it sure seemed to have a lot of headspace. Now I am not a gunsmith by any stretch, but I winged it on this one. I can take a .035" feeler gauge and get it between the closed bolt face and the back of the cartridge head. I can only assume this is way too much headspace correct? If so, does anyone know how to correct this problem? Thanks in advance for any help you can offer...........Rick H.

Fingers McGee
January 30, 2009, 12:06 AM
Headspace isnt causing the tab to break off. Timing is. The carrier is coming up before the bolt has retracted all the way and the case rim is hitting the bolt, breaking the tab. A little filing on the top of the carrier lifting lever so it will come up later, will solve the problem. I don't know what the proper distance between the case and bolt face should be; but if you are not have any problem with cartridges not firing when you pull the trigger, or with the extractor not grabbing the case rim after firing; then I'd say you don't have a head space problem.

Rick H.
February 1, 2009, 11:10 AM
Thanks for the reply Fingers. I looked at the timing issue and I don't think that is the problem. The carrier misses the bolt by quite a bit when working the action. My guess is that when a magnum round detonates it first goes forward by the firing pin and then gets smacked back .035" when pressures build. I think this backwards movement due to what I believe is excessive headspace, causes the shell rim to break the tab off the bottom of the bolt face. I was okay shooting .38 Specials thru the gun because the pressure levels weren't near what a magnum is and therefore the force generated by a Special didn't have the poop to break the tab. This is all just hypothetical right now because I don't have a new bolt to put in and try, but I need to know how headspace is set on these toggle link action rifles so I make sure it is right when I get a new bolt. Rick

Fingers McGee
February 1, 2009, 12:06 PM
Headspace is adjusted by the length of the toggles.