Hi all, I’m in the process of doing my research for an AR build and one of the routes I’m considering is getting a preban colt lower, stripping it and building on it.
Now I’ve done a lot of searching and reading and from what I can tell, these are the “incompatibility” issues I may run into with modern day uppers and components, but was hoping those more knowledgeable can provide clarification.
1. Sear block - will interfere with all modern day bcg’s and some triggers, namely geiselle? Shaving off the top of the block (diy) will allow a full bcg, but for the trigger you need someone to mill out the entire block?
2. Larger front pivot screw. From what I can see, there are offset pins that will allow you to connect a preban colt lower to any modern uppers pivot hole?
3. Larger trigger pins? I guess some triggers have large trigger pin models to solve this but otherwise normal triggers won’t fit?
These are the three possible “incompatibilities” I have found in my research but do all preban era colt lowers have all three of these things? Or are there some that don’t?
Thanks in advance
Now I’ve done a lot of searching and reading and from what I can tell, these are the “incompatibility” issues I may run into with modern day uppers and components, but was hoping those more knowledgeable can provide clarification.
1. Sear block - will interfere with all modern day bcg’s and some triggers, namely geiselle? Shaving off the top of the block (diy) will allow a full bcg, but for the trigger you need someone to mill out the entire block?
2. Larger front pivot screw. From what I can see, there are offset pins that will allow you to connect a preban colt lower to any modern uppers pivot hole?
3. Larger trigger pins? I guess some triggers have large trigger pin models to solve this but otherwise normal triggers won’t fit?
These are the three possible “incompatibilities” I have found in my research but do all preban era colt lowers have all three of these things? Or are there some that don’t?
Thanks in advance