Colt Cobra .38 special

oldknotty · September 1, 2014, 06:28 PM

I have a snub nosed Colt Cobra .38 special , the other day when i was shooting at the range the barrel came loose on it ????? I cannot get it to tighten up with the sight in line ?? What is going wrong here , how do i fix it ??
Thanks guys

James K · September 1, 2014, 08:13 PM

Have you had that gun since new or is it a recent purchase? What happened is not unknown, but usually happens when someone has replaced the barrel or has unscrewed it for some reason. I don't feel that tightening up that barrel is a DIY job since you need the proper receiver blocks and barrel wrench to avoid warping the frame. I suggest giving Colt a call and see if they will do the work; a local gunsmith might or might not have the tools, but Colt would be better.

Jim

Dixie Gunsmithing · September 1, 2014, 08:58 PM

I don't have one here to check, but I don't think they pinned those barrels after tightening. Anyhow, they torque down pretty heavy, and I'm wondering why it did this? Could something happened to stretch the thread?

James K · September 1, 2014, 09:21 PM

No, the Colts were never pinned, they were just torqued down. But Colt did adjust "windage" on those guns by turning the barrel (and thus moving the front sight) so it was not unknown for a barrel to unscrew.

There are several ways to correct the problem, but none I feel is a DIY project. You can roll the barrel shoulder, you can cut the shoulder back and cut the barrel off a thread (OK on a Colt, not on an S&W), or shim the barrel. In any case, frame blocks and a barrel vise are a necessity, and not all general gunsmiths have those.

Jim

Dixie Gunsmithing · September 1, 2014, 10:12 PM

James, yes I agree on the tooling, but if the barrel was tight beforehand, I can't see it loosening, unless it, maybe, had a lot of rounds through it, and it gradually did it over time from thread stretching. I could see using hot rounds, though, and it happening a lot quicker. However, I wonder what might have happened to the thread, and even with re-tightening, I wonder if it might cause it to prematurely do it again? I'm just wondering what would knock something that tight loose, or what the cause is.

Bill DeShivs · September 1, 2014, 10:30 PM

Look for a crack in the frame where the barrel screws in.

**4V50 Gary** · September 1, 2014, 11:13 PM

This is not a do-it-yourself job. I'd send it to Colt or take it to a competent gunsmith.

Scorch · September 2, 2014, 02:40 AM

Since Colt Cobras have aluminum frames, I would take a serious look at the threads to make sure the frame has not cracked.

James K · September 2, 2014, 02:06 PM

I mentioned the conventional ways of dealing with that problem, but I wonder if a thread blocker (LocTite) might not work. I don't think the torque is that great.

Assuming that there are no other problems, like a cracked frame, I think I might just try Blue LocTite if it were my gun.

Jim

September 1, 2014, 06:28 PM	#1
oldknotty Member Join Date: March 20, 2014 Location: Norwood Ohio Posts: 90	Colt Cobra .38 special I have a snub nosed Colt Cobra .38 special , the other day when i was shooting at the range the barrel came loose on it ????? I cannot get it to tighten up with the sight in line ?? What is going wrong here , how do i fix it ?? Thanks guys

September 1, 2014, 10:30 PM	#6
Bill DeShivs Senior Member Join Date: April 7, 2006 Posts: 10,981	Look for a crack in the frame where the barrel screws in. __________________ Bill DeShivs, Master Cutler www.billdeshivs.com

September 1, 2014, 11:13 PM	#7
4V50 Gary Staff Join Date: November 2, 1998 Location: Colorado Posts: 21,832	This is not a do-it-yourself job. I'd send it to Colt or take it to a competent gunsmith. __________________ Vigilantibus et non dormientibus jura subveniunt. *Molon Labe!*

September 2, 2014, 02:40 AM	#8
Scorch Senior Member Join Date: February 13, 2006 Location: Washington state Posts: 15,248	Since Colt Cobras have aluminum frames, I would take a serious look at the threads to make sure the frame has not cracked. __________________ Never try to educate someone who resists knowledge at all costs. But what do I know? Summit Arms Services

September 1, 2014, 08:13 PM	#2
James K Member In Memoriam Join Date: March 17, 1999 Posts: 24,383	Have you had that gun since new or is it a recent purchase? What happened is not unknown, but usually happens when someone has replaced the barrel or has unscrewed it for some reason. I don't feel that tightening up that barrel is a DIY job since you need the proper receiver blocks and barrel wrench to avoid warping the frame. I suggest giving Colt a call and see if they will do the work; a local gunsmith might or might not have the tools, but Colt would be better. Jim

September 1, 2014, 08:58 PM	#3
Dixie Gunsmithing Moderator Emeritus Join Date: April 27, 2013 Location: Ohio Posts: 1,923	I don't have one here to check, but I don't think they pinned those barrels after tightening. Anyhow, they torque down pretty heavy, and I'm wondering why it did this? Could something happened to stretch the thread?

September 1, 2014, 09:21 PM	#4
James K Member In Memoriam Join Date: March 17, 1999 Posts: 24,383	No, the Colts were never pinned, they were just torqued down. But Colt did adjust "windage" on those guns by turning the barrel (and thus moving the front sight) so it was not unknown for a barrel to unscrew. There are several ways to correct the problem, but none I feel is a DIY project. You can roll the barrel shoulder, you can cut the shoulder back and cut the barrel off a thread (OK on a Colt, not on an S&W), or shim the barrel. In any case, frame blocks and a barrel vise are a necessity, and not all general gunsmiths have those. Jim

September 1, 2014, 10:12 PM	#5
Dixie Gunsmithing Moderator Emeritus Join Date: April 27, 2013 Location: Ohio Posts: 1,923	James, yes I agree on the tooling, but if the barrel was tight beforehand, I can't see it loosening, unless it, maybe, had a lot of rounds through it, and it gradually did it over time from thread stretching. I could see using hot rounds, though, and it happening a lot quicker. However, I wonder what might have happened to the thread, and even with re-tightening, I wonder if it might cause it to prematurely do it again? I'm just wondering what would knock something that tight loose, or what the cause is.

September 2, 2014, 02:06 PM	#9
James K Member In Memoriam Join Date: March 17, 1999 Posts: 24,383	I mentioned the conventional ways of dealing with that problem, but I wonder if a thread blocker (LocTite) might not work. I don't think the torque is that great. Assuming that there are no other problems, like a cracked frame, I think I might just try Blue LocTite if it were my gun. Jim