The sport of shooting carries inherent risks and we don’t want anyone hurt while engaged in the sport and especially at our range. We strive to maintain a safe environment for the sport. We also understand and appreciate that special pride which come from working on firearms and do appreciate the work required to create a one of a kind firearm.
The AR platform provides more accessorizing than any other platform ever developed. Back in the day 70’s and 80’s , the 1911 style pistols enjoyed a similar popularity. Don’t misunderstand, there are some major differences. When you purchased an unfinished 1911 frame, the frame was machined, and complete with correctly-sized holes drilled in proper locations, slots milled to specifications, etc. there are stories about 1911’s going full auto because they were not properly assembled or the trigger group was reworked incorrectly.
Part of the romance with the AR platform is the ability to change the uppers receiver, providing a wide range of calibers and barrel combinations. Purchasing a AR style forging with the intention of making a safe, effective semi-automatic rifle without the proper tools and/or skills to properly finish the machining process could result in an unsafe firearm. Therein lies some safety considerations.
Please be careful when making modifications and keep safety utmost in your mind. I have personally witnessed several firearms that malfunctioned due to being incorrect assembly procedures. Check head-space when changing barrels and/or the carrier group. For example, the carrier group from your .223 will fit in your 300 blackout upper, but the headspace may need to be adjusted. In addition, properly modifying the trigger mechanism can result in tighter groups, while improper modifications can result in a firearm that double fires, or does not fire. either of these conditions render the gun unsafe and maybe even illegal. If you are not 100% confident in your ability to make the modifications so the firearm remains safe, take it to someone who can.
As a final safety check, be sure the work is checked by a qualified person who has the proper gauges and knows how to check the firearm.