Which parts do you need to change out in differant cal uppers with 223 lower ?
ie buffers, bcg
7.62 x39
300 acc
6.8 spc
9mm
ie buffers, bcg
7.62 x39
300 acc
6.8 spc
9mm
7.62x39 - barrel, mag, bcg, dedicated lower options for different mags. Not sure on buffer. No experience with this caliber in AR.
300 AAC Blackout - barrel. Everything else is same as .223. Just remember that 300 blk gas spikes faster and has different gas pressure than 5.56, so carbine gas length is ONLY for 16"+ uppers. Pistol length gas for anything smaller than 16". Same buffer, but depending on barrel length might start with carbine buffer.
6.8spc - barrel, bcg. There are dedicated mags to hold 30 rounds and make it feed more reliable. Otherwise, you can fit about 26 rounds in a standard AR mag. Magpul is making a dedicated 6.8 mag, but it requires a bigger lower and they're working with LWRCi on this for the custom 6.8 PDW SBR. I assume anything from carbine - h2 buffer depending on barrel length, ect.
9mm - bcg, barrel, mags, heavy 9mm buffer.
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Psa multi cal lower with heavy wolf buffer spring ,Psa h2 buffer
I've only had my newest 7.62x39 out twice about 100-150 rounds per time with a h2 buffer
going to try a h3 next. Make sure your using a stock or heavy hammer spring to have enough
hammer strike for those hard suplus primers. Using stoner mags from midway and they work pretty good.
have a promag and its a pos.
Be advised it kicks harder and when you switch back to 223 you will think your shooting a 22lr.
going to try a h3 next. Make sure your using a stock or heavy hammer spring to have enough
hammer strike for those hard suplus primers. Using stoner mags from midway and they work pretty good.
have a promag and its a pos.
Be advised it kicks harder and when you switch back to 223 you will think your shooting a 22lr.
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