I believe Riddler has the right time frame. The first ones would not have been out in '92, based on the following: My NPPL experience was '93-'95. Sometime in the latter part of that time I went to visit Glenn and wound up BS'ing with him about some some stuff. I was kind of bitching to him about how big and heavy and slow the Typhoon was (being a mag-sponsored guy myself) so we went in the shop and he showed me one of the Blazer bodies on his mill. There were a few raw bodies laying around. He was still trying to decide if he would use threads for the barrel. This was before ANY Blazer had gone out, or been anodized or anything, because I asked to shoot one and he said he still had to work out the 4-way mounting or something.
So, anyway, that was in the Sacramento shop, and he had been there awhile already from Gold Circle, and he left there sometime in '92-'93 I believe.