45acp revolver and light primer strikes

[ExMachina]

Very frustrating...I'm having major ignition problems with my S&W 22-4 45ACP.
The failures all look like light primer strikes and the rounds will generally go BANG with a second strike.

Ignition failure:
1)occurs with and without moon clips.
2)occurs with both Winchester and CCI primers
3)occurs with all types of brass
4)is not limited to one or two chambers
5)can even occur in single-action firing
6)occurs with a frequency of about 1 in 6 or 1 in 7 rounds

The gun is running a full power mainspring with a standard length firing pin.

Thus far I have only used my handloads and have fired ~200-300 rounds. I will be trying 100 rounds of factory ammo next, but am suspicious that there's something wrong with the geometry of the gun.

I know I need to try out some factory ammo but these same 45 acp handloads always run 100% in my autos.

Other than ammo, any ideas as to what could be causing this (like could the cylinder be too far forward?) This is a brand new gun and has never run reliably (which is too bad because it is really fun to shoot)

I'd appreciate any experience you guys have had with this sort of thing

Thanks

 

[dawico]

When I bought my S&W 29 it would do the same thing with my handloads, but my Ruger didn't. Turns out I was seating the primers in too far. If I kept them to proper depth, the gun worked fine. The firing pin on the Ruger protrudes quite a bit farther than on the S&W.

 

[PattonTime]

Light strikes

I was having same problem, I tried factory worked perfect.
Turns out I was seating too shallow, by the tiniest amount, no problems with 1911's
Lots of problems in various revolvers , I own several.
I was using a RCBS hand primer, same one for over 5 years and many, many thousands .
I guess the rod or something had worn just enough, switched to my Lee hand primer all problems went away.
Check out factory , best way to trouble shoot.I am cheap , but paying a little extra for some factory loads saved me a lot of trouble long term. If yours always go second strike
like mine did , it could be same problem.

 

[BCRider]

Something else to try is to flush out the revolver's action with some solvent and lube mix such as the Ed's Red mixture. After a few cycles of flush, work action to work out grunge, flush, work action, flush, etc so that the flushing stuff comes out clean allow to dry or even blow it dry with some compressed air. Try at the range again.

You can easily access all the action by merely removing the grips and squirting the flush up through the opening in the frame where the mainspring passes to the hammer.

The thinking here is that it's not the power of the firing pin but the velocity. A gummed up action will slow the hammer down from viscous drag. THink waving your hand in air vs waving it underwater. If your hammer is being slowed down by thick or gummed up oil it won't arrive at the primer with the right sort of speed.

In truth it could be any of the issues with primers or with the action noted so far. I offer this as one more possible thing to check.

 

[DeepSouth]

I have never had to use S&W's costumer service but from what I hear they are top notch. Call them and see what they tell you.

 

[rcmodel]

First thing to do is fully tighten the strain screw in the front of the steel grip frame.

If you have target stocks, you have to take them off to see it or tighten it.

BTW: You can't seat primers too deep.
They bottom out in the primer cup when properly seated.
That pre-loads the anvil and makes mis-fires from improper seating very unlikely.
They should be below flush with the case head when properly seated to full depth.

If they are not seated fully, you can get mis-fires because firing pin energy is used up trying to finish seating them.
Then they will go bang the second time.

rc

 

[ExMachina]

@BCRider, that's actually a really good idea about cleaning everything, one that I hadn't considered--for all I know there could be a burr that's randomly interfering with the firing pin.

Regarding primers, that was the first thing I tried to troubleshoot. I moved to "softer" primers (Winchester instead of CCI) and I also sorted my brass to remove the brands with notoriously tight primer pockets. After seating the primers, I only loaded cases where the primer was slightly below flush with the case head. If it was a seating issue, those steps should have done the trick, but my failure rate for these rounds remained almost unchanged from the previous 100 rounds.

The other step I'm considering (along with trying a bunch of factory ammo) is to install an extended length firing pin. I know that this can lead to punctured primers when using a full power mainspring, so I'll need to be mindful of that...

And if none of that works, then I guess the gun will go (back again) to the S&W service center (first time was for a new cylinder, which is why I was suspicious of the geometry) .

Please keep the ideas coming guys...

 

[dawico]

BTW: You can't seat primers too deep.
They bottom out in the primer cup when properly seated.


rc

The recommended depth is about 0.003" to 0.005", and I was seating them to 0.007" or more, and it was enough to cause misfires in my 629. I was new to reloading at the time, and possibly crushing them a little, but they fired perfectly in my Ruger after taking them out of my 629. Factory ammo fired perfectly in the 629. Seating the primers to the proper depth fixed the issue.

I am guessing most guns you would never notice with, but the firing pin on my 629 is pretty short. It could have been thin rims on the cases also, but I have to disagree, it is possible to seat primers too deep.

 

[Red Cent]

I agree with RC.

After thousands and thousands of reloading 38, 357, 44 spl, 44 mag, 45 Colt, 9mm, and others, almost any primer that did not fire the first will the second. There is the factory dud however. Or contaminated. But yours eventually fire.

I have seen numerous rifle and pistol fail to fire during competition and the bunch of us hollering "go around again" and they normally fired (single action revolver) on the second hit. Shooting as much as we do and the type of shooting we do, when the rifle goes click, we have taught ourselves to thumbcock and fire. The first strike finally seats the primer and the second strike does the job.

"The failures all look like light primer strikes and the rounds will generally go BANG with a second strike."

Understand that if a primer pocket was an inch deep and you were supposed to seat the primer flush with the case head, they would misfire to hell and back. If the primer pocket is formed to spec, you cannot seat it too deep unless you dimple or crush the primer.

I will not question your findings and/or your voracity. In my 60 years I have never had or seen the problem of deepseated primers.

Do me one favor. If you are handpriming, have someone else with experience (not slighting you) try it. If you are using a machine, go prime on another machine.

Good luck.

 

[RugerMcMarlin]

Do you have any trouble opening or closing the cylinder? Are these the moon clips you started with? Are any of your clips thinner than the rest?

How many times have you loaded these cases? have you measured case length? I think thats a more likely culprit for distance to primer.

What I'm getting at is with clips ,you should be head spaced off the rim/moonclip. Without it spaces off case mouth? Case length?

 

[ExMachina]

@Red Cent. Thanks and, I'm perfectly open to the suggestion that I'm not seating the primers fully...(however, I'll be dammed if I can get them to seat any further -- I've used both hand priming and the Lee Auto Prime 2)

Anyway, with the current 15% failure to ignite rate, factory ammo should pinpoint whether or not the problem is my reloading technique or the gun.

And so I'd still be interested to know if there is anyone who has had a wheelgun that consistently did not play well with factory ammo?--what were the causes of your problems (firing pin too short? frame geometry screwed up??)

This gun came from the S&W factory with a weird cylinder problem (one that S&W then fixed) and I just wonder if there is something more deeply flawed with this gun's frame...

 

[RugerMcMarlin]

Open your cylinder, and see if ejector rod is unscrewed, or loose.

 

[ExMachina]

@RugerMcMarlin: All 20 of my moonclips (still) lie flat and I seem to have the problem both w/ and w/o moonclips. Cylinder opens fine and the ejector rod appears to be tight.

@rcmodel: just had the gun apart. Innards are clean and I gave everything a good wipedown and re-lube.

I also took the opportunity to put in an extended firing pin...we'll soon see if that was a good idea

 

[RugerMcMarlin]

About all thats left is last line of post 11.

I don't know what it went in for first, but I suspect a shim/ barrel cylinder gap deal.

I did'nt think the clips would be bent , I meant thickness.

 

[john wall]

Take a fired large primer, pry the anvil out, tap the strike mark out with a punch and hammer, then put the primer on the strain screw. This will typically fix your problem. There are other ways to do this, but this is the free fix.

 

[ExMachina]

@RugerMcMarlin:

"I did'nt think the clips would be bent , I meant thickness."

That's a good point and one I haven't checked on. Thank you.

And your point just made me think of something else. Right now, I'm absurdly anal about loading the moon clips with the side of the clips which hasethe very slight raised edge (from being stamped out, I assume) always facing away from the cylinder. My thinking was that that extra few thousandths could cause enough flex dampen the hammer strike...however, that edge could also be causing the rim of the case to be cushioned too I guess. I need to look at some other clips to see how thick this edge should be.

And I just now read your edited post above and you're right, some of the cases I'm using are probalby out of spec from being loaded so many times...so thanks again

 

[RugerMcMarlin]

John Wall, has a good idea on shimming the tension screw on front strap. That should give the equivalent of 2 more threads of reach and a goodly amount of whack.

I would do that before I miked all my clips.

 

[ClemY]

One additional thing you could try is installing a longer firing pin. Brownell's has them and Apex. The longer firing pin will reach the deep set primers and will reach the deep set cases. The newer 625s are said to have slightly longer chambers. Loose rounds would tend to be affected. Since you are also having trouble while using clips, it could be your mainspring also.

 

[Chuck Perry]

RC gave you the best advice: check the strain screw. I've had two S&W 45ACP revolvers, and I had light primer strikes in both of them. I had light strikes even with an extended firing pin installed. Know how I fixed the problem? Tightened the strain screw all the way in.

 

[ExMachina]

I'm hoping that I might have solved this problem (still have to test fire it of course)

RugerMcMarlin got me started when I realized that I had not measured the moonclips. It was then that I realized what I really needed to measure was the revolver's headspace! So, instead of going through all my moonclips, I chambered an autorim cartridge and inserted a feeler gauge between the cartridge head and the recoil shield. Result: 0.015"-0.016". Then I inserted a loaded moonclip and measured. Distances were the same.

Then I found the following:
"Headspace: The distance between the cartridge head and the recoil shield is called headspace. There should be adequate space for the cylinder to rotate freely when loaded but not so much where the case can back out when fired. Center fire revolvers should have .006″~.012″ headspace, .010″ is optimum. Rimfire revolvers should have .004″~.008″ with .006″ as optimum."

So there might be the cause of my problem--the headspace on my gun around 0.005" thousands out of spec. The measurements on the longer firing pin indicate that it should be long enough make up for the extra gap...we'll see.

Thanks to everybody for their thoughts and ideas. They really helped.

I'll report back here after I get to the range again.

 

[RugerMcMarlin]

ExMachina,Sorry, been here all along, finally the snoring woke me up.

I don't know where you look but I would bet a dollar, that gap your measuring is supposed to be .006 greater to accomodate for the clips, I also think Autorim has a thicker rim, than others, like 38special.

I also think a light hit, is a light hit, with either firing pin. I think Walls idea of shimming,between strain screw and spring is the best fix. You said full power spring. What about the hammer,weight or configuration?

 

[RugerMcMarlin]

Alright, stupid idea, I can't remember,I think its right on Nframes, does the lower right side plate screw hold the cylinder crane in?

Reason I ask, I could see if you accidently switched it with one of the shorter screws.
I could see, it letting you fire 1 or 2, before recoil pulled it just enough forward, for subsequent stikes not to reach and or be light. And it still wouldn't be enough to notice when you opened the cylinder.

Pull the lower right screw off your other 625. and match it for length.

 

[ExMachina]

Autorim is supposed to headspace the same amount as a 45acp (moonclip or no).

And the screws are right (in the gun anyway )

 

[madcratebuilder]

Any chance a previous owner filed on the strain screw?

 

[ExMachina]

Spring tension looks to be maxed out: the mainspring is flat against the frame and does not look like it can be tensioned any more.