.45acp misfires in Ruger Convertible

[tailchain]

I recently purchased a Ruger Blackhawk .45 Convertible revolver. I prefer the .45 acp cartridge to the .45 Colt. I reload for all my .45 pistols and revolvers and have been doing so for years. I loaded some 200gr. LSWC bullets over 5.0 grains of Bullseye and took my new gun to the range. I also carried my Colt Gold Cup along for grins. To make a long story somewhat shorter, the reloads would misfire in the Ruger about every other cartridge but I had no trouble at all with the same loads in my Gold Cup. This is a load that I have used for years and years and loaded on the same equipment as well.
What I would like is your opinion on what is going on. I tend to think the Ruger may have a light hammer fall but I have never heard of such a thing with a Ruger. They usually shoot anything they are fed within reason. Please let me hear what you guys think.

 

[Unclenick]

The 1911 guns have very long firing pin throw. That can make up for a lot of priming sins. Try the following experiment:

Pick out a couple dozen cases. Deprime them and clean the primer pockets with a tool made for the job or the flat blade of a small screwdriver. The little metal handle ones sold by Radio Shack are good because they are straight sided. I won't recommend the primer pocket depth uniforming tools for this, as I would for a rifle case, because LP primer pockets are about 0.010" shallower than LR primer pockets, so the tools will cut to deep for pistol.

Once you have the pockets clean, prime them. Use the depth probe that sticks out from the back end of your caliper beam to measure how deep the the primers are in the pockets. You want them 0.003"-0.005" below flush. By trial and error, find the right seating pressure to land them there. Ideally they will be at least 0.003" deeper than they were when the primer anvils touched down in the primer pocket, but that's more measuring to achieve. The Forster Co-ax press priming tool just aims for 0.005" for all primers (sometimes 0.004" after spring-back) and it works well to set the bridge of the priming mix between the primer cup and anvil. What you are doing is optimizing ignition sensitivity.

Now finish charging these rounds and try them. If you still have failures to fire you need to examine the gun. Check firing pin protrusion (ask Ruger what it should be), and that the barrel-cylinder gap isn't too small (indicating a cylinder too far forward) with a feeler gauge. Should be around 0.005" give or take a thousandth. You may have a cylinder that was cut too deeply at the back. Ruger can tell you what things should measure.

Also, if you are not using Federal 150 primers, try some. They often work when others are marginal.

 

[serf 'rett]

Primer make? Some are hard, some are soft and it could make a difference in a revolver.

Will the round fire with a second strike in the revolver? If so, it may be the primer isn't fully seated.

 

[Edward429451]

I had problems with ignition of Winchester primers in my 1911 so switched to Fed 150's and never had a problem since. I have a BH Convertible also and never had a mis-fire with it (but it's only been fed Fed 150s though).

Try some Fed primers and be sure to seat them good.

 

[WIL TERRY]

CHECK THE CRIMP on your handloads. IF it is too much the case can go a bit too deep into the chamber and the firing pin cannot properly whack the stew out of it[SAAMI SPEC lingo]
Firing pin protrustion: .055" min , .060" MAX, .0575" OPTIMUM. USE your firing pin quage to measure it.
And so it goes...

 

[cornbush]

Sounds to me like the cases are too short for the Blackhawk or the crimp is too much for the Blackhawk.

They headspace on the case mouth, so too much crimp or a short case can lead to misfires.

 

[CherokeeT]

It is also possible the cases are a tad (tech measurement) short and works fine in the GC because the extractor holds the case against the breach, doesn't happen with the Ruger; Or, the GC chamber may be a tad (tech again) shorter than the Ruger chambers. Just some thoughts, My Ruger 45 ACP's work fine with the proper taper crimp.

 

[smokin54]

Is this a new Gun ? is it possible a previous owner cut a few coils off the main spring to lighten the trigger pull ? How does it do with 45 colt ? Do you know it left the factory with that 45 acp cylinder or did some one add it later ? it should have the last 3 numbers from the s/n marked on the rear with electric pencil . i have fitted a acp cylinder to my 45 colt , they are not always a drop in

 

[Unclenick]

Duh!

Tail Chain,

Per Wil Terry's comment, SAAMI specs for .45 Auto show that with a bullet in place the outside diameter of the case mouth must be between 0.467"-.473" for proper headspacing. Also, if your cases have been previously fired and reloaded, note that unlike a rifle cartridge, .45 Auto cases tend to shorten slightly with each load cycle (about half a thousandth, typically). After resizing and before seating a bullet, use your calipers to make sure they are between 0.888" and 0.898" long. If they are shorter, that can cause ignition issues.

Also, having now looked through the instructions, make sure the three digits on the two cylinders match the last three digits of your gun's serial number. They need to match for the cylinder to be the one fitted for the gun at the factory. It's always possible in a gun store that had more than one, for the cylinders to have been swapped into the wrong frame.

 

[243winxb]

Headspace problem, brass to short or chamber to long or too much taper crimp. Have seen 1 chamber cut to deep, always misfired. (i did not read all of above)

 

[mmb713]

My Ruger Blackhawks annihilate primers, like dented almost clear through. They are both stock internally so I doubt it is the gun.

 

[dreamweaver]

it's a timing issue. send it back to ruger. call ahead and plead your case. bet they fix it for free.

tom

 

[snuffy]

it's a timing issue. send it back to ruger. call ahead and plead your case. bet they fix it for free.

tom

If that was the case, the primers would be getting hit off-center. The OP didn't say anything about that. It would also be spitting bullet lead all over.

But it is a concern. Tailchain, slowly cock the hammer, see if when the sear catches if you can rotate the cylinder further. Or is the cylinder locking lug engaged? That's what Tom is referring to. Ideally the lock lug should engage the cylinder notch at the exact same time the hammer comes to full cock, and the trigger sear locks.

 

[dreamweaver]

snuffy said it better than i did.

tom

 

[Wallyl]

Ruger .45 ACP BHK

Tallchain,

Had the same problem.. I tried just about everything...and still many misfires. I wrote to Ruger---sent it back...they fixed it and it works just fine now...they never did tell me what they did to fix it. It even will shoot short cases. I have found that using a stell sizer die will lengthen the brass more than will a carbide sizer die..but I don't know why that is. In the .45 Colt I find a steel sizer die sizes the cases better as well...the carbide sizer sizes them too much.

 

[Unclenick]

The steel sizer includes the taper in the auto cartridge case, where a carbide sizer is just a ring that sizes the whole case to the same diameter. That can flow brass to the rear where the taper of the steel pushes inward more with less rearward massage. My .45 Auto cases, shooting light target loads, actually lose about half a thousandth of length per sizing cycle in a carbide sizer. I've never run the experiment with steel, though, which might be interesting to try.

Also, Redding now has a carbide sizer design with two carbide rings. The ring near the case mouth is the same size as current carbide sizer rings, but the lower ring is wider to maintain the taper. I don't know how that will compare on final length, but it should work the brass less, improving case life for those firing loads at near maximum.

 

[Wallyl]

.45 ACP sizers

I have tried fired cases of the same length, sizing one batch in a Lyman carbide sizer and the other with an RCBS steel sizer die---the steel sized cases always come out longer...