Colt Forum banner
1 - 19 of 19 Posts

·
Registered
Joined
·
582 Posts
Discussion Starter · #1 ·
First, thanks to dfariswheel for his quick response on my previous post about the weak hand spring on my just-acquired Magnum Carry.
Another trip to the range revealed that while the hand is now coming out okay, the gun appears to be suffering from light strikes.
It's true this is with my own reloads, but the exact same boxes of ammunition had no failures to ignite in either the Smith 66 or Colt .357 I had along. The primers were dented to a medium degree, I would have to say, not just a light dink, but far from the near-destruction caused by the .357.
I also have a DS-II that has shown a similar affliction and am wondering if the SF series is prone to this like the Smith 625s.
I can't see anything unusual-looking with the mainspring, such as no kinks as in the old dowel-in-the-spring "trigger job".
The gun does appear to have been shot a fair amount, but is not worn-out seeming or rattly.
If a new mainspring is needed, would there be a recommended source? Numrich is out of stock.
Thanks
Bill
 

·
The Searcher
Joined
·
11,097 Posts
How is firing pin protrusion? Don't know what it should measure, but you might eyeball it. How about flushing out the firing pin channel good with Gunscrubber or the like if you have not. Then there's the question of headspace. Again, don't know the spec, but for most D frame .38 spl it's .060 - .065. For I frames including .357 it's .062 - .070. :cool:
 

·
*** ColtForum MVP ***
Joined
·
15,802 Posts
What I recommend:

Test fire with FACTORY ammo. I know, your reloads are good in the other guns, but this is THIS gun.

Second, test fire to determine if the misfires happen ONLY in double action, or also in single action.

As above, make sure the gun is clean, INCLUDING the cylinder chambers.

Check the firing pin for free movement, sticking, or broken/worn/altered tip.

Re-tension the mainspring by putting a little more bend in the top leg.

If you suspect the firing pin, replacement is a factory ONLY job. Replacement REQUIRES a special press and support dies.
 

·
Registered
Joined
·
582 Posts
Discussion Starter · #4 ·
I'm trying to figure out a way to measure firing pin protrusion better than just eyeballing an adjacent shim. If I had to guess, I could only say it's better than .032".
I don't know about checking headspace, but the barrel/cylinder gap measures a tight .006, and so does the cartridge face/firing pin plate gap. Both measurements taken independantly, of course.
I will see about cleaning out the firing pin chamber.
Okay, dfariswheel, I will somehow break down and buy some factory-made ammo. Nothing hurts a reloader worse, you know. But I see the need. Besides, all of this was loaded on a Dillon 550, which while good, has never matched my old Lee hand primer for perfection.
Winchester primers were used in cleaned brass, but I can't say the primer pockets were treated.
The chambers do show signs of a fair amount of .38 usage, with the resulting hint of cruddy chamber fronts. I had already decided to get after them due to the hard extraction of full-power ammunition I've experienced so far. As mentioned elsewhere, 158gr Gold Dots departing around 1100fps leave empties that require some pounding to get out, while they just drop out of my other guns mentioned.
The gun is far from battered, so I would be surprised at a worn-down firing pin or other such problem.
Fired single-action? This gun can be fired single-action? I forget how!
Thanks for the much-appreciated assistance.
Bill
 

·
Registered
Joined
·
36 Posts
Seem to recall Brownell's makes a device to do this but it costs a few bucks. I would use a feeler gauge to get a better guestimate of the protrusion which should be 0.050-.055" per Brownells. Also, check cylinder endshake as if excessive it could cushion the firing pin blow. I have also seen mention made by another person measuring firing pin protrusion using a range rod and a micrometer. One measurement of length protruding from the barrel is taken with the firing pin at rest and another at protrusion. Seems to me it could be somewhat inaccurate but I am not a gunsmith.
 

·
Registered
Joined
·
582 Posts
Discussion Starter · #6 ·
At dfariswheel's suggestion, I went out and actually bought a couple of hundred rounds of .357 Lawman ammunition. Ouch. Until I get to fire it, though, I will add that I did an old-fashioned firing pin test by putting an unsharpened #2 pencil down the upraised bore and snapping the gun. The pencil's flight was short and weak, barely a foot and a half of elevation.
The Magnum Carry was even weaker than my recent-model Smith 66.
Contrast this to its' safemate .357 Model, which seemed to almost stick the eraser into the ceiling plaster.
Endshake was minimal, as I recall, only a two or three thousandths.
Off to the range soon.
Thank you all
Bill
 

·
Registered
Joined
·
582 Posts
Discussion Starter · #7 ·
Re: Magnum Carry light strikes- range report

A test firing session with a box and a half of Speer Lawman JSP .357s produced a sore trigger finger and a goodly number of failures-to-fire of the light strike sort.
My carefully-made .38 wadcutters did no better. In some stretches, there was a miss once out almost every cylinderfull.
Upon returning home (I dislike tearing down revolvers on shooting benches at outdoor ranges), I added a bit of bend to the upper leg of the mainspring as dfariswheel instructed. It sounds and feels stronger while being snapped, at the expense of some increase in trigger pull.
Equally distressing is the difficult ejection with .357 loads, even some that are none too hot- a 158gr Berry's at 950fps. With full-power loads, sometimes pounding is required.
The characteristics are interesting- the cylinderfull begins to eject, with all of the cases easily moving the first quarter-inch. Then, one or sometimes two stick, fairly hard.
The chambers were carefully cleaned beforehand and looked excellent, especially smooth and almost shiny.
I began to think it was chamber erosion from too many .38s having burned a tiny wide ring in the chamber and allowing the longer .357s to expand enough at their mouths to make them resist extraction where the chamber returns to normal diameter.
I will be happy to entertain suggestions for fixes.
Thanks
Bill
 

·
*** ColtForum MVP ***
Joined
·
15,802 Posts
Re: Magnum Carry light strikes- range report

Obviously, someone bent the mainspring, which is really stupid because the SF frame Colt's had about the lightest DA trigger pull ever used on a revolver.

The sticky extraction is an odd one. Usually the cases stick without ANY movement.

I have no idea what might cause them to stick after 1/4" of free movement.

In this case, I'm going to suggest cutting to the chase, and sending the gun in to Colt.
Specify that the mainspring is weak, and explain the sticky extraction problem.
 

·
Registered
Joined
·
36 Posts
Re: Magnum Carry light strikes- range report

I seem to recall when the SF VI came out the mainspring was light as Shooting Times tested one with a double action of about 8.25 pounds. I think a number of people had trouble with misfires and Colt would up replacing some mainsprings. Puzzling, though, in that the Magnum Carry was several years after this. Maybe one of those weak mainsprings found its way into your gun. My Mag Carry out of the factory had around a 12 pound double action. After having the gun tuned when playing with mainsprings misfires would set in around 8.25 pounds. Now the double action is at 9 pounds without misfires. I would still try to see what the firing pin protrusion is on the gun.
 

·
*** ColtForum MVP ***
Joined
·
15,802 Posts
Re: Magnum Carry light strikes- range report

The weak spring on the early SF guns was actually a too-light trigger return spring.

Some users had problems with slow trigger return causing stoppages. The weaker spring would cause the user to start pulling the trigger again before it had moved far enough forward to reset.

In the manuals, Colt offered to replace the trigger return spring if the customer had the problem.

Since Colt used the same mainspring they'd used in the older "D" framed guns, there was no weak mainspring issue I'm aware of.
 

·
Registered
Joined
·
582 Posts
Discussion Starter · #11 ·
Re: Magnum Carry light strikes- range report

The SF-frame mainspring is the same a the D-frame one? Then what I'll try next is grabbing one of the D-frame springs I have making reliable fire in my older guns and see what comes out.
After having bent the main as mentioned about, the pull is a bit stiffer, indeed, almost like a Smith without the gravel.
I wish I had a pull measuring device, but my instinct suggests that it used to be in the eight-pound range.
Maybe the spring was just tired out.
I should throw in that my DS-II has some trouble with light strikes as well, but not as bad. The pull was a bit heavier than the MC was before yesterday.
Lotta sideplates coming off soon.
Thank you all.
Bill
 

·
Registered
Joined
·
36 Posts
Re: Magnum Carry light strikes- range report

[ QUOTE ]
The weak spring on the early SF guns was actually a too-light trigger return spring.

Some users had problems with slow trigger return causing stoppages. The weaker spring would cause the user to start pulling the trigger again before it had moved far enough forward to reset.

Since Colt used the same mainspring they'd used in the older "D" framed guns, there was no weak mainspring issue I'm aware of.

[/ QUOTE ]

Thanks for clearing that up, Dfaris. As the Mag Carry I have originally had about a 12 pound DA I gather perhaps that Shooting Times maybe got a "ringer" that was factory tuned to get that light of pull (8.25 lbs). Numrich shows a DS II/SF VI pn of 182940 and pn of 175160A for the DS/Diamondback. When playing with the Mag Carry I bought some additional mainsprings from Numrich and they definitely never yielded a low trigger pull, though (not 8.25).

Many years ago some magazine had an article on a Cylinder & Slide super tuned old style Colt DS that had a double action of about 7.5 pounds or so that worked. However, that obviously was not used to fire magnum primers.
 

·
Registered
Joined
·
582 Posts
Discussion Starter · #13 ·
After doing the mainspring tensioning recommended by dfariswheel, plus even more scrupulously cleaning the firing chambers, I took my Magnum Carry down to the club range yesterday for a short session.
I went through about fifty full-power 150gr Speer Lawman rounds, plus about another hundred of my standard full-power .38 loads throwing a 158gr Berry's round-nose at about 750 in the short barrel.
There were no failures to function at all.
Extraction of the .357 empties was a little stiff but not out of line, although there was still more stickiness than the accompanying Smith 66 and 28.
My buddy and I found it to be an exceptionally accurate snub- even with the .357 ammunition, I was able to reasonably stay on a 12" plate at 12 yards and get a good percentage on another at 20 yards. This is about as good as I will ever do with shorty sights and middle-aged eyes.
I am surprised at how manageable the little gun is even with ferocious 158gr Gold Dots in the low-to-mid-1100s range. Not fast for the second shot, and it's hard work to get a truly quick pair off with hits, but quite satisfactory.
This was all with Eagle Secret Service grips. With the original Hogues, control and speed are definitely better. But I'm a wood sort of guy and that's that.
If the extraction issue remains tolerable, I will just keep on using the gun. At this point, I am inclined to trust it for serious use.
It still has the nicest action of any snub I've ever had, even with the spring increase.
Incidentally, I did observe my friend firing it single-action a few times, so I know it is possible.
Here's a gratuitous photo of it with the (heavily-speedloader-relieved) Eagles. Note also the polished trigger done by the Gun Doctor of Roselle, IL, which greatly improves the comfort level.
Thanks,all
Bill

 

·
The Searcher
Joined
·
11,097 Posts
I was going to suggest something like a Lewis lead remover for the chambers, but I didn't want to step on any toes. Even "crud" shines. Well, maybe not crud, but hot deposits. I am surprised every time I look through a bore or chamber at a slightly different angle with a bore light. :cool:
Oh, I'm glad it's working well and I was going to ask about the sharp trigger, but you have that dealt with. Here's another gratuitous photo. ;)
 

·
Registered
Joined
·
582 Posts
Discussion Starter · #15 ·
Well thank you for the gentlemanly reply, sir, and I shall throw in a picture of the MC's safemate DS-II, with Pach grips covering the back of the Waller shroud.
Bill

 

·
Registered
Joined
·
265 Posts
I'm glad you have worked out the problem with your Magnum Carry. I bought the first one I saw, had Detective Special shroud installed, and added Mustang grips:



Mine has a very smooth action.

John
 

·
Registered
Joined
·
36 Posts
Cherry River: Glad the Mag Carry is working now. Perhaps polishing the chambers would help cure your extraction issues. I'll let DFaris comment on this further. Yes, on mine I also found the trigger sharp including the tip to my hand. Had the trigger built up and configured to a (gulp!) S&W combat style that was a little bit wider and very contoured for double action shooting. No more finger problems. Enjoy!
 

·
Registered
Joined
·
582 Posts
Discussion Starter · #18 ·
I continued to clean the chambers vigorously and Sunday after our club's non-standard "two-gun" IDPA match (backup and competition guns in each stage, in that order). I ran another hundred through the MC without a hiccup, including good extraction. Indeed, it seems as though there was some sort of a .38 crud ring still in there escaping my visual inspection.
Ironically, a squadmate at the match was using an MC for the BUG portions and went home with a bloody trigger finger. Upon seeing my modified one, he became determined to have the Gun Doctor (Roselle, IL) do up his trigger as well.
I chose to shoot my bobbed Agent for this one, which I have smaller grips on and therefore find it more suitable for the BUG category.
Of course, I ran a Combat Commander in the comp gun section for a complete Colt look.
Bill
 

·
Registered
Joined
·
21 Posts
CherryRiver,
I knew it was you when I saw the picture of the Carry Magnum posted above. I have posted my trigger problems on a thread in the revolver section and was pleasantly suprised to see that you post here. You are right, probably have the only two Carry Magnums in the area and yours really stands out. It is a bueatifull gun.
Stan
 
1 - 19 of 19 Posts
Top