Barrel ridge on EAA Witness .40 S&W

[Jeffdg]

Hello!

I have a EAA (Tanfoglio) Witness Limited .40 S&W in which I have about 3000 reloaded (flawless) rounds with the following recipe:

5.1 gr AA#2

180 Gr FMJ (Montana Gold)

OAL = 1.160"

Fed primer

After a great shoot today, I was cleaning the gun and noticed some ridges on the barrel. I could spend quite a bit of time trying to describe what it is, but you'll see it in the picture. I cropped it to make the file size smaller, so the front of the barrel proceeds to the right of the picture. It's not entirely obvious in the picture, but it's only happening on the side of the barrel featured in the pic; if I turned it over, the barrel looks 'normal'.

Please advise on what is causing this (before it gets any worse!). One of my thoughts is it could be a mismatch between the load and mag spring. This recipe was advertised as a pretty light load, and the recoil speaks to this, very little snap. Other than that, I'm clueless. The fun has been functioning flawlessly, so it's a bit of a mystery.

The limiteds come with 3 springs - one installed and two with specified parameters. Does anyone know which is in the gun (hard to know if changing it will make it stiffer to less stiff)?

Thank you for the help!!!

[abs]

My guess would be too light of a recoil spring. It looks like the gun is unlocking prematurely.

[Joe4d]

If that was a Browning design I would say the barrel isnt fit properly and your shearing the locking lugs.

[Silver_Surfer]

Looks like some kind of battering is happening. Whats your power factor?

The EAA's are similar to the CZ's?

Edited March 2, 2009 by Silver_Surfer

[L9X25]

Either that barrel is soft (not heat treated properly), lugs are not fully engaging, or your loads are way over pressure. It is also possible that it is a combination two or more of these factors.

[Jeffdg]

Most of my shoots have been at local (non IPSC) clubs, so my PF is about 160 (vel < 900 fps). These are pretty light, low-recoil loads.

Either that barrel is soft (not heat treated properly), lugs are not fully engaging, or your loads are way over pressure. It is also possible that it is a combination two or more of these factors.

[ebg3]

Looks like an improper fit. EAA should fix it for you.

[Carlos]

These are both 75s. About a dozen or more manufacturers around the world make 75s. The 75 is used by more Governments, Militaries, Police and Security agencies than any other pistol in the world.

The design is strongly influenced by John M. Browning's last design: the Browning P-35 High Power; I have a barrel from a WWII era Browning which fits right into the slide on any of my 9mm 75s (though it won't fit the frame as the lockup/lugs are different, and the frame rail arrangements are different). Still, the influence is obvious.

Being a JMB design, I agree with those above RE battering causing the lugs to fold over. That gun will eventually seize up and stop functioning. I believe EGW in PA, or Canyon Creek could repair it for you.

Looks like some kind of battering is happening. Whats your power factor?

The EAA's are similar to the CZ's?