Thank you all for the information. I would just like to open this thread back up to anyone else that may have experience in changing barrels in the roller-lock system vis-à-vis reliability. Does changing barrels on roller-lock guns lower reliability? Specifically, the SP5k comes with a 4.5" barrel and the B&T replacement barrel is (It actually doesn't say on HK parts, but on this install video looks to be an inch longer : approximately 5.5"). https://www.youtube.com/watch?v=_M9DXR5POqo
Here is that B&T barrel. Any help on its length would be greatly appreciated as well. https://www.hkparts.net/shop/pc/B-T-...8-82p17955.htm
Additionally, just to cross-reference some information on the HK SP5k, as I had mentioned the paddle release was an easy drop-in installation, it appears the newer 2019 Sp5k's marked BK, from what I've read, have this block that must be removed in order to install the paddle release:
Interestingly, at the end of this tutorial thread, bauerdb has an SP5k marked BK that does not have this block. Older SP5k's marked BH and BI, according to the posts in the thread above and below, do not have this block.
EDIT: I'm seeing BG stamps on gunbroker, any info on SP5k's stamped BG?