|
|
02-22-2016, 06:27 AM
|
|
Member
|
|
|
Join Date: Oct 2008
Location: Baton Rouge, LA
Posts: 968
Likes: 1,729
Liked 808 Times in 378 Posts
|
|
Model 19 & light primer strikes
At my last range session, I noticed my Model 19 no dash had light primer strikes with certain .38 ammo. In the past, I had this issue with cheap ammo, such as imports or WWB 38s. However this time it happened with such quality loads like .38 Golden Saber and Buffalo Bore. On the other hand, my defense loads(.357 Golden Saber, Federal 357B and 357E, as well as the Remington .38 FBI load) worked fine. The mainspring screw is factory tight. Could this be simply an ammo issue or a problem with the gun? Thanks for any advice.
|
02-22-2016, 06:47 AM
|
SWCA Member Absent Comrade
|
|
|
Join Date: Nov 2002
Location: SLC, Utah
Posts: 5,062
Likes: 739
Liked 3,271 Times in 1,282 Posts
|
|
Items to be checked would include:
1- Is the gun's lockwork clean? Grit or gummed lubricants slowing down the hammer fall?
2- Look at the firing pin. Its it intact? I had one on my old K-38 shatter once and it fired irregularly for a couple rounds before breaking the rest of the way and stopping all shooting.
3- Has the mainspring that powers the hammer been replaced or thinned down? Less powerful spring reduces the amount of "smack" the hammer and firing pin can provide to the primer.
4- Has the screw that pushes on the mainspring, the strain screw been shortened? If it has, it also reduces the amount of "smack" available.
5- Shooters finding their strain screw shortened excessively have taken a spent primer cup, scraped out the broken anvil and any remaining primer ash and placed it on the end of the screw, giving the screw some temporary extra length and thus allowing it to put more pressure on the spring for more hammer "smack."
If none of these resolve the problem, order a new mainspring and strain screw and install them.
|
The Following 3 Users Like Post:
|
|
02-22-2016, 08:17 AM
|
Member
|
|
|
Join Date: Jan 2009
Location: Metro Detroit, Michigan
Posts: 6,919
Likes: 179
Liked 4,294 Times in 2,106 Posts
|
|
Another potential cause is a short hammer nose, the part that forms the firing pin. I had a 19-3 with this problem and the fix was a new hammer nose made my Power Custom and purchased from Brownells.
The test for a short hammer nose is very simple. What you do is open the cylinder, Pull back on the cylinder release to free the lockwork, then pull and hold the trigger all the way back after the hammer falls. Then take a US dime and lay it next to the point of the firing pin projecting through the firing pin bushing. The amount of projection should be equal to the thickness of that dime or slightly more. If your revolver passes the Dime Test then move on to Buff's list.
Now, one note about the Strain Screw in the front of the grip frame. It's not a well circulated aspect but the length of this critical screw can vary due to the vintage of the revolver. On my Round Butt 19-3 I was surprised to find that the original, fully blued strain screw on this new acquisition was distinctly longer than a recently purchased spare strain screw purchased for a Round Butt L frame revolvers in my spare parts stock. My only other choice at that point was the primer cup "shim" that Buff suggests.
BTW increasing the DA trigger weight to over 11 lbs with this trick provided no solution to the misfire issue and that is when I found that Power Custom hammer nose will work perfectly in a 1972 vintage model 19 in spite of that note about compatibility on Brownells.
Because you have a 19 No Dash it's obviously a good deal older than my 19-3 but since you won't be able to find a 1950's vintage hammer nose easily it may be the only resolution available and I suspect that it will work. So, if your model 19 fails that Dime Test it's worth the cost of trying it. Just make sure to read the excellent fitting instructions carefully and test for projection and function before staking the supplied rivet in place.
|
02-22-2016, 11:43 AM
|
|
Member
|
|
|
Join Date: May 2012
Location: Evansville, Indiana USA
Posts: 6,203
Likes: 480
Liked 11,333 Times in 3,505 Posts
|
|
Along with the good info above, you should also check for end shake, and confirm the rear gauge is within specifications for your model 19.
Correct gauge between the rear cylinder face and the breechface should be .012" - .014".
__________________
Ret. LE, FA Instr, S&W Armorer
|
02-23-2016, 07:54 AM
|
|
Member
|
|
|
Join Date: Oct 2008
Location: Baton Rouge, LA
Posts: 968
Likes: 1,729
Liked 808 Times in 378 Posts
|
|
Thanks for all the advice. I will certainly look at each part and see what the issue could be. Considering the single action pull "feels" a tad bit lighter than my experience with other K-frames it could be a shortened strain screw. The thing that gets me that all soft strikes occur with .38s, and they fire on the second time around. The Magnums never fail to fire on the first hit. I suppose this could related to case length and the Magnum primer, though I am just guessing.
|
02-23-2016, 04:48 PM
|
Member
|
|
|
Join Date: Jan 2002
Posts: 1,862
Likes: 1
Liked 460 Times in 228 Posts
|
|
Sometimes they simply bend the stock mainspring to reduce spring force. Only way to spot that is take it out and lay it next to a stock one and check the curve. The more curve, the less spring force.
|
|
Thread Tools |
|
Display Modes |
Linear Mode
|
Posting Rules
|
|
|
|
|