CastleLurkenstein from United States, PA Public Profile

I really like this product. It's very lightweight, so if you're looking to shave off a few oz from your build and are running out of places to do so, this is a solid consideration as compared to a milspec QD endplate and castle nut combo. It also looks pretty sharp.

Installation is a breeze. The endplate ring that goes around the buffer tube is wide enough There is no need to stake the castle nut (and no mechanism to allow for it, even if you wanted to anyway). You just hand-tighten and twist the nut roughly 1/4 turn beyond that, and you should be good to go.

If you do want to torque it, Fortis recommends only going to 15-20 ft-lbs and NOT exceeding that amount. I would...agree with that, because I was an idiot who just used standard torque values and went to about 25 ft-lbs, which resulted in marring the finish on this fancy-schmancy-looking castle nut. (The good news is that this thing is shiny enough you may not even really notice unless you look carefully.) So, avoid my mistake and either just hand-tighten, or only go to about 15 ft lbs., just to be safe.

The finish is glossy black and shiny whatever-anodized-color-you-picked.

Lastly, one potential "con" is that the endplate QD connector does not have any kind of anti-rotation locking. This is less of an issue for me, but might matter to you.

So, overall, I found the SHIFT pins to be a pretty solid product. Normally for installation of the pivot pin, I use a Wheeler tool with a clevis pin to install the spring and detent. It's a helpful "cheat" that makes installation a lot easier than using just your hands. The SHIFT pins eliminate the need for that tool.

I didn't find the design especially helpful for the takedown pin, however, which I found still required regular installation. Not the end of the world, but something to consider.

The one flaw that I see with these pins is that the 90-degree angled channel which allows for turning the pins to make for easier installation/uninstallation creates a bit of a hang-up point when popping them in and out. With an upper installed, this is less of a problem, but even there, they can hang up just a bit.

I don't regret buying them, but I'm not sure I'd buy them again. I'm giving this a soft "yes" on the "Would you recommend this product?" If you (A) don't want to buy a separate tool to make pivot pin installation easier, and/or (B) think you might uninstall pins at some point in the future, these are a good buy. If you already have a pivot pin installation tool, I think these are fairly unnecessary, especially for the price.

One other thing: the finish is basically milspec phosphate, in case matching finish matters to you.

I have used these on two builds so far, and have a couple more for future builds. In my experience, the BCM Mk2 recoil mitigation system does what it says and more. First, obviously, you will notice a softer shooting platform as compared to a standard milspec carbine buffer. The Mk2 is a little longer, uses a rifle spring, and a heavier buffer vs a milspec setup. You can further tune this by swappi gout the rifle spring for your spring of choice (e.g., Geissele, Tubb flatwire, Springco, etc.) and/or switching to a heavier buffer (e.g., T1 up to T4 vs T0).

Second, the Mk2 system can help improve ejection patterns, especially when shooting suppressed. I use a hybrid flow thru can (CAT AC556) and consistently see ejection around 3 o'clock with a T2 buffer in the Mk2 tube.

At this point, if budget isn't an issue, I would absolutely put this on any rifle I build, and would seriously think about swapping out the milspec setup on any lower or rifle I'd buy.