If i have a 300 blk pistol, can I swap uppers with a jakl 556 upper? The lowers are sold as 556 and 300 blk, so seems theres some difference there?
Thanks!
They are interchangeable. The lowers are all ar15 milspec compatible once you strip the good bits off. I believe you can also throw those same bits onto any other milspec lower and go ham.
Disclaimer: not an expert, just a nerd
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Thats my impression too.
They have different 556 and 300 jakl lowers listed now, so im wondering whats different between them.
Is it because they are engraved with the caliber?
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I think that’s it, thanks!
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welcome to the forums @jbarnes7952 !!
and yes they are interchangable just as kastaway said
If you’re going to run an interchangeable 5.56 and 300BLK on a VERY similar platform with the exact same STANAG magazines, I highly recommend getting some magazine bands or tape of different colors to avoid loading a 300BLK cartridge into your 5.56 chambered upper.
I know guys will say “oh I’ll never do that I’m competent,” but all it takes is once and best case scenario you ruin your gun. Worst case? I hope you don’t take shrapnel in your money maker.
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I might be wrong, but I’m pretty sure the only difference between them is the engraving on the lower. Makes it easier to SBR with a specific caliber already engraved as opposed to “MULTI”