Plenty of folks build 16 inch carbines, and plenty more build ARPs, but there is a dedicated subset of those that build true, full-size rifles.
For these, it’s hard to beat a 20 inch AR upper, if only for the number of benefits that a 20 inch upper can confer.
Let’s start with these 5, which are arguably the most important.
A flatter trajectory: Because the longer...
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