Main Spring Adjustment Screw 1873 Rifle

[Skiddsteer1]

Good morning Pards! I have an older Navy Arms Uberti 1873 in .357 mag short stroked. I have begun to have light primer strikes (Federal primers) and wanted to tighten the small screw on the bottom tang. I originally wanted to tighten it about 3/4 turn but was unable to tighten it only a short way before it was already tight. At this point I do not think that the firing pin has any dried grease on it but will check it anyway. In the event that is fine. what is my alternative with the mainspring adjustment screw? Thanks Skid.

[Kid Rich]

Several things you can check. The bolt face-make sure it has not become peened by many primers being hit, it may be that the fp hole is closed a little. Firing pin channel- clean it with a good cleaner and a pipe cleaner. Also check the fp spring it may be a little stronger than needed. Mainspring may be weak from years of use.  Check the hammer to make sure crud is not between it and the frame. FP extension- make sure it is clean as well as the channel it runs in. Check to make sure your primary main spring screw is tight. ALL of these parts have to be free of crud and properly lubed in order for that little primer to go bang.

[Skiddsteer1]

Thank you Kid Rich.

[Skiddsteer1]

Kid Rich. is the larger screw on the tang the main spring screw?

[Abilene, SASS # 27489]

yes

[Sarge]

One other thought.  check the firing pin OAL against a new firing pin.  I had the very tip of a firing pin break off clean, causing light hits.  

[Randy Saint Eagle, SASS # 64903]

You may have done this but I always had better luck loosening the main spring screw, tightening down the tension screw some and then tighten back the main spring screw.

 

Randy

[Abilene, SASS # 27489]

2 minutes ago, Randy Saint Eagle, SASS # 64903 said:

You may have done this but I always had better luck loosening the main spring screw, tightening down the tension screw some and then tighten back the main spring screw.

 

Randy

Nate Kiowa Jones has mentioned in the past how he likes to adjust the screws like that.  Of course, I don't recall the exact detail, but it was something like: 

 

1. Loosen both screws.

2. Tighten the main screw all the way, then back it off one turn (?).

3. Tighten the strain screw until it just touches the main spring.

4. Tighten the main screw.

 

Maybe NKJ will chime in.

[Colorado Coffinmaker]

Depending on who did the Short Stroke work, I'd suggest checking the Firing Pin and Return Spring.  Your rifle says Navy Arms and that was a Uberti product from a good long while ago.  The older OEM firing pins were not necessarily of sufficient length and had the head was short.  Newer Firing Pins and After-Market firing pins are slightly longer and most include a reduced return spring..  Also, your Main Spring may be just plain tired.

[Skiddsteer1]

Thanks all. I took rifle apart. cleaned out the hole where the firing pin and spring goes and put in a less robust firing pin spring. The face of the bolt was indeed peened on one side. I Flitzed this out and it is smooth. I adjusted the tension spring and main spring as per your instructions. Cleaned and lubed the rest of the rifle. In the event the main spring is just plain tired. what are my alternatives if any? Tomorrow I will see if this rifle flies at the range, take it apart again and make observations and likely will report back. Skid.

[Abilene, SASS # 27489]

If you do get any misfires, turn the strain screw in a quarter turn at a time.  If you need a main spring, a stock spring can be had from VTI, Cimarron, Taylors, Dixie.  I'm not sure if anyone is selling a reduced power spring these days, but if so someone will know.

[Kid Rich]

The main springs from Taylors are not as heavy as OEM and you have to do little if any spring reduction to make them serviceable. I bought the extra length fp's for our rifles.

kR

[The Surgeon]

Long Hunter sells sure hit light or super light mainsprings. if you do need to replace yours. I'd personally go with the lightened version and not the super light unless you only shoot federal primers.