Hello do all colt preban lowers have the large hole,  are there any postban colt lowers with large holes,  are all colt lowers with a slab side preban or are there any post ban lowers with this look, thanks

TheLaw, nothing is ever certain where Colt's are concerned.  While not an expert, I can help you with a couple of things.  To the best of my knowledge, all of the slab-sided models were pre-ban and were SP rifles or one of the Green Label versions.  The SP1 series all had the large front pin. I believe the Green's all did as well, but am not certain of this.  The Blue Label rifles used both.  I have seen R6601's in the 040xxx range that had the large hole.  I recently saw one in the 083xxx range with the small hole, however it was not drilled for the push-pin detent.  Another oddity with Colt was their use of large trigger and hammer pins.  The Mil-Spec size is .154, but Colt used pins that were .170 for many models.  I believe that all Greens used the standard pins and the Blues the large pins.  The bottom line with Colt is that there are no hard and fast rules.  Colt mixed and matched parts as they saw fit to keep up with production and their ongoing effort to make PC rifles.

Amen. It's because of this kind of mix and match that Colt colectors go nuts!

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