s+w M66 main spring / strain screw?

Ammo Junky · February 21, 2007, 07:25 PM

I have a M66-1 that is misfireing. I plan to instal a wolf mainspring. My question is how much tension do I put on the strain screw? Just snug? firmly tight? Tighter than hell plus three more turns?
Tia
AJ

Bill DeShivs · February 21, 2007, 07:47 PM

If the screw is not tight with the factory spring it may be causing your misfires. The strain screw must be tight. If someone has shortened the screw it can cause the same problem.
Bill

bullfrog99 · February 21, 2007, 09:50 PM

As I was abruptly told by an aquaintance, "screw the (dang) thing in all the way and leave it alone!". Considering FTF's seem to occur when fiddling with it, i'm inclined to agree...

inkie · February 22, 2007, 01:43 AM

After you install the Wolf parts you can adjust the strain screw to your liking by screwing it in until it takes a good set. Shoot it, If it feels fine leave it. If not, back off a turn and shoot at least 12 rounds if it goes bang and your happy with the way the trigger pull feels leave it, if not back off a little more until your satisfied. Try different ammos If no misfires occurr your good to go. If you get some misfires tighten the screw until none occurr.

Ammo Junky · March 10, 2007, 03:15 PM

Quote:

If the screw is not tight with the factory spring it may be causing your misfires.

Yep, that was it.

The only expereince I have had with leaf type main springs is in singe actions where you just tighten the screw down and that is it. From now on that is how I will deal with the m66 type as well.
Thanks
AJ

Bill DeShivs · March 10, 2007, 11:40 PM

Please listen- The strain screw on S&W D/A revolvers should ALWAYS be screwed down tight! If it is not tight, the screw can back out, causing misfires. Never "adjust" the strain screw.
Bill

Dfariswheel · March 11, 2007, 08:08 PM

Exactly RIGHT.

The S&W strain screw IS NOT a trigger adjustment screw.
Per factory specs, it MUST be screwed down TIGHT and must stay tight.

Failing to keep the screw down tight will allow the screw to back out under recoil, WILL cause misfires and can cause the mainspring to "knuckle".

Dave Haven · March 11, 2007, 10:04 PM

+1. That screw has a head on it for a reason. Bottom it out.

February 21, 2007, 07:25 PM	#1
Ammo Junky Senior Member Join Date: March 11, 2006 Location: IL Posts: 537	s+w M66 main spring / strain screw? I have a M66-1 that is misfireing. I plan to instal a wolf mainspring. My question is how much tension do I put on the strain screw? Just snug? firmly tight? Tighter than hell plus three more turns? Tia AJ __________________ Will work for brass. I apologise in advance for spelling errors.

February 21, 2007, 09:50 PM	#3
bullfrog99 Senior Member Join Date: August 19, 2000 Location: Southeast Michigan Posts: 811	As I was abruptly told by an aquaintance, "screw the (dang) thing in all the way and leave it alone!". Considering FTF's seem to occur when fiddling with it, i'm inclined to agree... __________________ Are you a gamer? Try Fortress Forever, It is a free HL2 Mod. http://www.fortress-forever.com/?a=media

February 22, 2007, 01:43 AM	#4
inkie Senior Member Join Date: October 20, 2006 Location: Eastern Pa. Posts: 137	strain screw adjustment After you install the Wolf parts you can adjust the strain screw to your liking by screwing it in until it takes a good set. Shoot it, If it feels fine leave it. If not, back off a turn and shoot at least 12 rounds if it goes bang and your happy with the way the trigger pull feels leave it, if not back off a little more until your satisfied. Try different ammos If no misfires occurr your good to go. If you get some misfires tighten the screw until none occurr.

February 21, 2007, 07:47 PM	#2
Bill DeShivs Senior Member Join Date: April 7, 2006 Posts: 10,981	If the screw is not tight with the factory spring it may be causing your misfires. The strain screw must be tight. If someone has shortened the screw it can cause the same problem. Bill

March 10, 2007, 11:40 PM	#6
Bill DeShivs Senior Member Join Date: April 7, 2006 Posts: 10,981	Please listen- The strain screw on S&W D/A revolvers should ALWAYS be screwed down tight! If it is not tight, the screw can back out, causing misfires. Never "adjust" the strain screw. Bill

March 11, 2007, 08:08 PM	#7
Dfariswheel Senior Member Join Date: May 4, 2001 Posts: 7,478	Exactly RIGHT. The S&W strain screw IS NOT a trigger adjustment screw. Per factory specs, it MUST be screwed down TIGHT and must stay tight. Failing to keep the screw down tight will allow the screw to back out under recoil, WILL cause misfires and can cause the mainspring to "knuckle".

March 11, 2007, 10:04 PM	#8
Dave Haven Senior Member Join Date: February 1, 2000 Location: near Flagstaff, AZ Posts: 790	+1. That screw has a head on it for a reason. Bottom it out.