Thinning of barrel on a Colt replica

[Zo0tie]

Long ago I bought a couple of Colt 1851 Navy replicas just for fun. I've shot them a few times and have had fun with the whole Wild West fantasy. However something has always bothered me. Just above where the loading lever attaches to the barrel a bit of the barrel has been machined away, thinning the wall of the barrel. I've really had no problem with the guns but I've noticed than many replicas have this little indent on the barrel. If it were at the barrel end I'd not be concerned but the indent is pretty near the forcing cone where pressures would naturally be highest. I've noticed many replicas have this little feature. Is this part of the original design or is this just sloppy machining on the part of the manufacturer? I wonder if enough barrel thickness is left to be safe especially with the non-historical 44 caliber Navy Colt.

 

[Kansas Jake]

I’ve never read or heard of one exploding when using black powder or substitutes such as Pyrodex. I imaging an obstructed barrel might be more prone to give way there.

 

[Zonie]

Long ago I bought a couple of Colt 1851 Navy replicas just for fun. I've shot them a few times and have had fun with the whole Wild West fantasy. However something has always bothered me. Just above where the loading lever attaches to the barrel a bit of the barrel has been machined away, thinning the wall of the barrel. I've really had no problem with the guns but I've noticed than many replicas have this little indent on the barrel. If it were at the barrel end I'd not be concerned but the indent is pretty near the forcing cone where pressures would naturally be highest. I've noticed many replicas have this little feature. Is this part of the original design or is this just sloppy machining on the part of the manufacturer? I wonder if enough barrel thickness is left to be safe especially with the non-historical 44 caliber Navy Colt.

After looking at dozens of pictures of original Colt cap & ball revolvers I'll say, the undercut is the result of sloppy machine setup and tolerancing.

None of the original Colt 1851's I looked at had a undercut like the one in your picture.

As far as safety goes, I wouldn't worry about it. The walls on your revolver's cylinder chambers are thinner than the thickness of the barrel where the undercut exists and the pressure in the cylinder chamber is far greater than the pressures at the location of the notch in the barrel.

 

[Zo0tie]

Thanks for the replys. Yeah I don't feel too uncomfortable about the notch. But I'm surprised no one has brought it up anywhere else on the net. It's so visible. Gun people are usually pretty safety conscious. I know if a cylinder didn't line up precisely on a particular replica model there would be a lot of screaming. And clearances of the cylinder gap, whew! If it is sloppy machining I amazed it hasn't been corrected by the manufacturer even if it is only cosmetic. Replicas are supposed to be exact copies of the original.

 

[Rat]

Methinks the barrel cylinder gap is kind of like a pressure relief valve. All the blown up revolvers I've seen, it's the cylinder that usually bursts.

 

[hawkeye2]

"Replicas are supposed to be exact copies of the original."

If that were true there would be no brass frame .44 caliber '51 Navies. I don't believe I have ever seen a Navy without that cut and I expect it's a quick and easy (read inexpensive) way to mill out the loading lever slot rather than sloppy machining. I have never heard of one suffering any type of failure because of the cut,.36 or .44. Remember these are built with 20th. century technology not 19th. and also to sell at a price point.

 

[Eutycus]

Colt 1851 Replicas. Is this " indention" under the barrel visible on differant makes or is just one specific maker guilty of sloppy machine work? Would you by chance care to reveal which manufacturer made your replicas? Now I need to go check my ASM.
Oh, welcome to the forum.

 

[Eutycus]

Actually my ASM has the undercut also.

 

[Zo0tie]

My steel frame 44 Navy is marked Hawes Firearms which I believe was Armi Sao Paulo. And my brass framed 36 Navy appears to have been a kit gun marketed by Richland Arms. Both have the indentation of different depth deeper on the 36. Both seem to fire well despite that. Like I said I got them long ago.

 

[SDSmlf]

I have six 1851 Pietta Navys, all 36 caliber. They all have the cutout, HC or not.

Wouldn’t worry about barrel integrity, 36 or 44 caliber. Mine were used in SASS competition and saw multiple cylinders shot through them multiple times a month for years. Both cap and ball and conversion cylinders (no comment). As they say, they were ridden hard and put up wet. With no issues or concerns with barrel. Any pressure concerns would be in the cylinder, and that is not a concern here. In my opinion.

 

[Eutycus]

Every manufacturer seems to have his own version of the "exact copy". Ever notice parts aren't interchangeable? It seems they all differ ever so slightly from each other. Metric screws, arbor length, grip shape, etc. It would seem that exact replicas would be identical to the original. Any one have an explanation as to why original Colts do not have this undercut? Why just replicas?

 

[SDSmlf]

Every manufacturer seems to have his own version of the "exact copy". Ever notice parts aren't interchangeable? It seems they all differ ever so slightly from each other. Metric screws, arbor length, grip shape, etc. It would seem that exact replicas would be identical to the original. Any one have an explanation as to why original Colts do not have this undercut? Why just replicas?

Have worked in manufacturing engineering for a long time. Simple answer as to why everything is not interchangeable and/or identical to originals, everyone typically is using their own set of blueprints, tolerances and manufacturing processes.

It is a constant challenge to make sure replacement parts that are truly interchangeable even when supplied by the OEM. In some cases even parts made to the same print and tolerance don’t interchange because of the processes used to make them.

 

[SDSmlf]

I did take down one of 1851s last night and looked at the barrel undercut. Pietta could have avoided it by using a different diameter cutter and/or changed the depths of the cutout for rammer.

 

[Russ T Frizzen]

I did take down one of 1851s last night and looked at the barrel undercut. Pietta could have avoided it by using a different diameter cutter and/or changed the depths of the cutout for rammer. View attachment 13471
View attachment 13472

The only new Colts that don't have this notch are the 2nd gen guns from Colt. I guess that Colt doesn't use a fly cutter on their revolvers.

 

[Eutycus]

It's been several days since this "blemish" has been brought to our attention. I'm sure many a member examined their revolvers . I know I did. Is this undercut present on other models as well?

 

[desi23]

It's been several days since this "blemish" has been brought to our attention. I'm sure many a member examined their revolvers . I know I did. Is this undercut present on other models as well?

Every octagon barrel Colt replica I can remember handling over the years has this cut but it does vary in size. Different makers seem to have different tolerance levels for the dimensions of the cut. You will also see it on Dragoon barrels and the various Confederate copies whether they use a navy style or Dragoon style barrel. It is also different in appearance from original Colts as the Italians use different machining methods to make the cut than Colt did in the 1800's.

 

[Eutycus]

Okay thanks, the only replica revolver I have in that category is a Navy. Just wondering about any others.

 

[bang]

I believe this is a clearance cut for ram mechanism clearance plus to ease ram mechanism removal.

 

[SDSmlf]

I believe this is a clearance cut for ram mechanism clearance plus to ease ram mechanism removal.

Don’t believe this cutout is a’defect’ or weakens rhe barrel, but have you actually looked at one? Extra depth cut in barrel provides no required clearance or easier ram removal.

 

[bang]

Don’t believe this cutout is a’defect’ or weakens rhe barrel, but have you actually looked at one? Extra depth cut in barrel provides no required clearance or easier ram removal.

Own 4. Just speculation.