AMT Backup and WWB .380 problem - hard primers or weak spring?

[White Horseradish]

During my range session yesterday I was unpleasantly surprised by a new-to-me AMT Backup (SA). I kept having fail-to-fires. I was using WWB ammo from Walmart.

Examining the failed rounds I saw that they all had a definite pin impression on the primer that I would have thought would be enough to set them off. The strikes do not look light at all.

So, should I blame the ammo and try to find some other inexpensive practice round, or do I need to try and find if anyone makes a replacement mainspring for the SA Backup?

 

[rcmodel]

WWB is the crappiest & weakest .380 ammo made today.
But if you are getting good primer dents, it should at least go off!

I haven't head of mis-fire problems so much, but it won't feed in a lot of guns, and only gets 750 FPS or so out of short barrels like the AMT & Kel-Tec.

Try Federal American Eagle, or Sellor & Belliot if you can find some.


rcmodel

 

[1 old 0311]

S&B has hard primer problems in SOME weapons, but it is quality stuff. Give a box a try.

 

[White Horseradish]

In all fairness, I only had one fail-to-feed with it, and I think it was a deformed bullet.

The only gun/ammo combo where I had primer hardness issues prior to this was CZ-52 with Yugo 7.62 Tokarev subgun ammo.

I'll try Federal.

Is there some comparison of primer hardness between different manufacturers somewhere?

 

[wally]

Its real common for "trigger jogs" on the AMT backup make the gun totally unreliable do to weak primer hits. Try replacing the mainspring, will make the trigger heavier, but reliable firing is paramount. Before you do this give the gun a good cleaning and make sure the firing pin channel is not clogged with gelled lube or and/or dirt.

--wally.

 

[White Horseradish]

Cleanliness is not an issue here. This thing has been stripped down to last tiny pin and scrubbed shiny. An absolute PITA to take down, let me tell you...

Any idea where I couldget a new spring? Wolff doesn't list a DAO and a SA Backup, and the only spring kit it has says "firing pin spring included". Are they talking mainspring?