Split the forcing cone on an Army Special .41 Colt

[Muddyboot]

I split the forcing cone on a 4" Army Special today on the left side. I was using my reloads, 5 grains of Unique under a 200 grain lead Buffalo bullet.
Have been using the same load for a almost two years on several different .41 Army Specials without problem. Was my load to hot?, here are the pics. The bullet used is the Buffalo Arms 386" 200 Grn. HBRN 20-1 for 41 Colt

[rwsmith]

I don't like the way the metal is blown so far outward. Maybe that spot in the forcing cone was weak or soft (bad heat treatment?) or overload. I'd expect an overload to CRACK the metal rather then bend it like that.

How old is that model???

[Muddyboot]

Originally Posted by rwsmith

I don't like the way the metal is blown so far outward. Maybe that spot in the forcing cone was weak or soft (bad heat treatment?) or overload. I'd expect an overload to CRACK the metal rather then bend it like that.

How old is that model???

It shipped From Colt in 1928

[Bkreutz]

That looks suspiciously like a timing problem. (just my impression)

[Muddyboot]

Originally Posted by Bkreutz

That looks suspiciously like a timing problem. (just my impression)

The timing on the revolver was not to bad, which is why I liked to use it,. However it's been suggested that the bullet may have hit the cone.

[Waywatcher]

That's a bummer.

Conventional wisdom with over-pressure is that it should harm the cylinder first.

Was it still timing right, is it still timing right?

[x10x10]

maybe a worn lock while timing was good it picked this time to slip a little on you, Mabye a good smith can cut off the forcing cone and get the barrel out and screw in a barrel or maybe time to make it a custom gun,

sorry about your luck, hate to loose a valued piece

[Muddyboot]

[QUOTE=Waywatcher;137787797]That's a bummer.

Conventional wisdom with over-pressure is that it should harm the cylinder first.

Was it still timing right, is it still timing right?[/QUO

Prior to the crack ,the timing was very good, in fact, much better then most of my other Colt's of this model. Which is one of the reasons I used it regularly. The cylinder is undamaged, but won't rotate now due to binding with the cone.

[Muddyboot]

Originally Posted by x10x10

maybe a worn lock while timing was good it picked this time to slip a little on you, Mabye a good smith can cut off the forcing cone and get the barrel out and screw in a barrel or maybe time to make it a custom gun,

sorry about your luck, hate to loose a valued piece

I know I can find a barrel, but finding a 4" barrel will be very hard as they are the least made in this model.

[scooter123]

Count me as another who thinks this was a fault in the timing. Because of the cylinder rotation on a Colt I suspect that the hammer fell well before the cylinder was carried into lock. As for the cause, it's likely either excess wear on the single or double action sear.

[Alk8944]

I seriously doubt any of the other responders have any experience with .41 Colt from the comments. Sorry for the loss. I have been looking for a .41 Army Special or O.P. for years, but guns and funds don't seem to come into conjunction very often.

As you know the barrel shank of the .41 is very thin. From the deposits on the frame it looks like this developed over several rounds, not just 1. In spite of the fact that the older Lyman books listed 5.0/Unique as a maximum load with the 386178 hollow-base bullet I would have to say that that is really a bit heavy for use with a hollow-base. Lyman shows this at just under 900 FPS, which is considerably higher than factory velocity with the similar bullet in loaded in later ammunition. My recollection is the published factory velocity was something under 750 FPS. With the sole exception of the Single Action Army the barrel shanks of all other .41 Colt revolvers are very thin. I keep loads for my 1894 New Model Army and Army Special (converted from a .32-20 by re-boring) down to 800 FPS and have had no problems.

It is for exactly this reason that loads with hollow-base wad-cutter .38 Special loads are kept down, to avoid splitting the barrel shank!

[Muddyboot]

Originally Posted by Alk8944

I seriously doubt any of the other responders have any experience with .41 Colt from the comments. Sorry for the loss. I have been looking for a .41 Army Special or O.P. for years, but guns and funds don't seem to come into conjunction very often.

As you know the barrel shank of the .41 is very thin. From the deposits on the frame it looks like this developed over several rounds, not just 1. In spite of the fact that the older Lyman books listed 5.0/Unique as a maximum load with the 386178 hollow-base bullet I would have to say that that is really a bit heavy for use with a hollow-base. Lyman shows this at just under 900 FPS, which is considerably higher than factory velocity with the similar bullet in loaded in later ammunition. My recollection is the published factory velocity was something under 750 FPS. With the sole exception of the Single Action Army the barrel shanks of all other .41 Colt revolvers are very thin. I keep loads for my 1894 New Model Army and Army Special (converted from a .32-20 by re-boring) down to 800 FPS and have had no problems.

It is for exactly this reason that loads with hollow-base wad-cutter .38 Special loads are kept down, to avoid splitting the barrel shank!

I've been shooting the 5.0 grain load for years with out problems, but several different reloaders I've talked to believe the load was on the hot side. That with a possible timing issue caught up with me in what ended up a very expensive lesson. So lesson learned the hard way, I'll reduce the load in the future along with inspecting the forcing cones in my other Army Specials very closely.

[Cpo1944]

I`m sorry you learned the hard way- as I always do-. Please post how the repairs go and what you intend to do with it. Thanks, Jack

[rwsmith]

Does the fracture appear to have been impacted by a lead bullet? It seems like if it were a timing issue some lead deposit or some sign of bullet sliding across the damaged area might show.

[Jellybean]

I'm inclined to agree with Alk, too much pressure over a period of time.

Lyman's 5 grains of Unique has been around for a long time and may have been developed with balloon head brass. Not to mention any differences in newer hotter primers and possible differences in bullet specifications. Check your other guns over carefully.

[WR Moore]

I was going to suggest setting the barrel back, but looking at the profile, I don't think that's going to be possible.

The forcing cone looks oversize, almost a chamfer. If that's accurate, probably weakened the barrel shank.

[Muddyboot]

Originally Posted by rwsmith

Does the fracture appear to have been impacted by a lead bullet? It seems like if it were a timing issue some lead deposit or some sign of bullet sliding across the damaged area might show.

Yes, it appears to me that some of the cone was hit by the bullet, it's hard to tell from the pic, but my guess is that the cone caught some lead and the load was on the hot side....

[shil]

First, I am sorry your fine revolver is damaged and hope you can get a replacement barrel. It sure looks like an off-center bullet strike, since Colt DA cylinders rotate clockwise. The damage is in the right place. Correct me if I err, but Colts of that vintage had two pawls on the hand; one for initial carry-up and the second to make sure carry-up was complete and allow the locking bolt to engage its cut in the cylinder, holding it tight as the trigger was squeezed. Wear on the second pawl would probably be accelerated if it had to complete the carry-up stroke. Once that second pawl wears enough, ouch. I own two early Colts; a 1917 New Service and a 1938 Detective Special.

[Jellybean]

If it were an off center strike/timing/alignment problem, the proof would be in the primer.

When firing pins hit the outer edges of a primer they often fail due to the fact that there is no anvil support under them.