Replace Diamondback Main Spring ??

[Denny Crane]

I recently bought a 4" .38 DB with a real rough box. Other than some bluing wear on the muzzle the gun is in great condition. The guy said he bought it new and hadn't shot more than a couple hundred rds. He also said it had not been altered.

The only problem I have with it is lite strikes. In DA it might miss 2-3/6 and will miss one or more in SA. I figure the main spring must be weak so I order a new one. In SA the trigger would break at 3.5lbs.

I bought the new spring from a place I found online called MDS Gun Repair for about $29 or so.

I got the new spring and went to install it when I noticed it looks thicker than the one in the gun. I have no way of knowing if it is original. The new spring also has a tit on the right side that the one in the gun doesn't have.

The top 1/2 of the new spring is slightly longer than the one in it? Just enough that it was difficult to get the spring in and the hammer pin in place but it did fit. I had to have the trigger pulled and the hammer fully forward in fired position to get the hammer pin in the spring cradle.

Now it will not cock in SA however it does pull through in DA. When cocking it in SA the hammer stirrup hits the back of the hammer. In DA it doesn't?

Is it just the wrong spring? 1/16" too long? Or am I doing something wrong?

The spring that was in it (original?) has a multi colored bluing look to it not just unfinished steel like the replacement. Maybe it isn't the OEM spring?

Any advice?

Thanks

[dfariswheel]

Wrong spring.

The old pre-war Colt DA revolvers had forged "V" springs with the small locating stud on the end.
That won't work with your Diamondback.

All the post-war "D" frame Colt's like the Detective Special, Cobra, Diamondback etc used the same spring.
You might find a new spring here, part number 29:

Numrich Gun Parts Corp. - The World's Largest Supplier of Firearms Parts and Accessories

[Denny Crane]

That's the guy I was looking for!

The "stud" on this spring is not on the end? It is about 1/2 way up the top 1/2 of the "V" on the right. It is very close to being identical, close enough that I wanted to be sure it wasn't right.

[retiredgunsmith]

You have definitely received the "pre-war" style spring with the locating stud inyegral.

Your Diamondback uses spring # 56090, which I have a supply of NEW GENUINE OLD stock.
I can be reached at LSZD263@aol.com
Robert

[A1A]

Just for the record and others information, here is a picture courtesy of member coltpython showing the older grip frame and mainspring. The spring appears to float, but the stud goes in a hole in the web. Compare to your DB where the end of the spring sits in the notch.

[kenhwind]

SARCO lists Police Positive mainsprings. I bought two, they look pretty nice, but I'm not sure if they are OEM or re-pro. Definately more tension than the one in my DS. These springs are for the later guns as they have no alignment stud and look like my original.

[Denny Crane]

Thank you Retiredgunsmith.

The new spring came yesterday and I put it in today. It is identical to the original.

Lite strike problem solved.

Anyone need a new spring for the older grip frame as shown above?