Light Primer Strikes

I

Igiveup

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I have been working on an M10-7, and did a spring job on it. The package said "reduce power" and I'm thinking the main spring might be too light. I took it out today (stepped out back door) and had three no-fires. Do you think I should put the original spring back?
 
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When I used to chase the light trigger pull after changing ou the rebound spring I would leave in the stock main spring and turn out the strain screw until I got misfires then turn it in until I never had any. THEN I would count the 1/4 tuens until it was tight again. They are 32 to the inch screws sso each turn is .0312 and a 1/4 turn is .0078. Take the number of 1/4 turns by .0078 and then remove the screw and carefully measure it and then file ALMOST that amount off. Leaving a little extra is not a bad thing.. Round off the edges slightly and reinstall tight.

I believe a smooth tigger is more important than a light trigger. I finally hit on trying to becoming a better trigger puller.
 
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In my experience, light strikes and misfires have been fixed with a new hammer spring and is the same cure for both Colt and S&W revolvers. With Colt, you can actually bend the V-spring to make it work OK again.
 
Igiveup said:
I have been working on an M10-7, and did a spring job on it. The package said "reduce power" and I'm thinking the main spring might be too light. I took it out today (stepped out back door) and had three no-fires. Do you think I should put the original spring back?
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If you make any changes to a gun and it doesn't work afterward then un-do whatever you did! Absolutely re-install the factory spring!
 
what is the gun used for, a range toy or do you bet your life on it? if a range toy you might find ammo that works 100% of the time as it has a softer primer.
if you reload use a softer primer, if not replace the factory spring.
 
Go to the notable threads section of this forum and read the thread on Revolver Trigger Job Questions. You will find all your answers from the S&W Armorers manual pages shown.

Stu
 
Reduced power main springs lead to lighter firing pin impacts, this can be enough to cause failures to ignite the primer.
 
The reduced power springs are meant to be used with a properly full length strain screw in place. Some providers of said magic springs will send you a longer strain screw. I learned to trust the factory spring and make adjustments to it-see post #3.

My one trial of the reduced power spring showed that in long shooting sessions, it let down enough to cause misfires. It'd recover with a rest, but that's not behavior I'll tolerate.
 
All good ideas. I went to replace the original sping this morning and discovered that the strain screw was about three plus turns loose. I tightened it and everything goes bang for now. I will do more shooting before I declare problem solved. I have been "building" this M10-7 that came without barrel from J&G Sales. It has been a great learning experience, but I am by all means a gunsmith. Just learning.
 
All original works best. Many who must have springs replaced with something lighter never took the time to become accustomed to the original setup, which works well, just as it was designed to do. And it's as reliable as you can get.
 
The very first time I tried a "reduced" power spring, I saw the "v" groove down the spring, and then the strain screw wouldn't compress the spring near as much as the flat original spring. Replaced the original spring and never bought another reduced spring.
 
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