My experience with my TEC-9
Well first of all - the manual has certain ammo recomendations. One of the recomendations is to not use reloads - ever - period. The second recomendation is to not use ammo with a case thickness of less than .027, and the third recomendation is to only use ammo made after 1984.
It's widely known that the weapon will not feed anything but FMJ, the weapon will jam with hollow point or wad cutters or anything else like that. It's basically made to fire NATO ball. (actually I found that Nyclad 124gr semi-hollow points work just fine in it) But beside Nyclad, I've never been able to feed HPs in it without a round jamming on the feed ramp. With regular ball ammo - mine works just fine. When I was first breaking in the pistol I had some jams, but that cleared up. I actually have not had any problems with it and I've put about 700 rounds of FMJ through it since the original break-in period.
My TEC-9M is also fairly accurate. But I purchased my pistol new in 1987. It's about as accurate as my Browning Hi-Power. I can shoot 3" groups at 25 yards.
Intratec was basically sued out of existance by rabid gun-control activists. Quality at Intratec took a dive in mid-1987. Although the company succesfully defended itself against a major lawsuit, the legal costs were devastating. There were cost cuttting measures, less money spent on quality control and the quality of the TEC-9s declined.
By late 1989, the gun banners in CA decided to ban both the TEC-9 and TEC-22 by name in the state's Roberti-Roos Assault Weapons Ban. Intratec got around this fairly easily: Company owner Carlos Garcia just changed both of the guns' names. The TEC-9 became the TEC-DC9. Although you'll find some folks that say this was to "screw over" Washington, DC, it actually stands for "Designated California."
A friend of mine purchased a DC9 and I was surprised at how horrible the quality was. The "fixed" front site was not only crooked, (from front to back it was at maybe a 9 or 10 degree angle to the line of the barrel) it was also off center (meaning it wasn't welded on the exact top of the upper receiver. The smallest shot group I recorded was a little over 5 inches. We fired about 150 rounds through it with no jams.
I purchased my TEC-9M for $167.00 - including taxes.
So anyway that is my experience with the TEC-9.