View Full Version : Light firing pin strike

June 14, 2009, 11:07 AM
Have a colt that works fine in single action but has a light firing pin strike in double action. What is cause and cure???

guy sajer
June 14, 2009, 12:28 PM
After you've eliminated a possible bad lot of ammo (have you tried different ammo ?) , I would assume a weak main spring .

What model is it ?

June 14, 2009, 01:07 PM
I have not tried the ammo change. It is a COLT Diamondback. Everthing I read says a poosible mainspring problem thanks.

June 14, 2009, 01:39 PM
Most likely the mainspring has taken a set. Numrich has them (http://www.e-gunparts.com/product.asp?chrProductSKU=175160A) for $11.50, though the label says it is for the Colt Agent, it is what is linked to from the Diamondback parts list, so I assume the two use the same spring. You can get a spring cryo-treated to limit how much of a set it takes. Just do any fitting work to lower trigger pull first.

guy sajer
June 14, 2009, 02:43 PM
I have not tried the ammo change.
Might be worth a try . We ran into a batch of CCI 38 Spl ammo this year with apparently hard or not fully seated primers . Tried different ammo and all is well .

If not , Nick's got you dialed in to a replacement spring :cool:

Jim Watson
June 14, 2009, 04:30 PM
Take the grips off and look at the mainspring.
If the top leg of the V spring has a bend about midway from tip to V, it has been "raftered" as a cheap way to reduce the trigger pull. Also the ignition, as you see.