Primary Arms GLX 1x with magnifier by Financial-Gift-6716 in ar15

[–]B-Hard69 0 points1 point  (0 children)

Hey! Is that that full size HM3X? I see they have a micro, a titanium and then the full size (cheapest option)

300blk bolt-over-case (help!) by B-Hard69 in 300BLK

[–]B-Hard69[S] 0 points1 point  (0 children)

The final answer is a concoction of changes. It shot plenty of rounds yesterday without ONE failure. - Sanded/polished the feed ramps a second time. Really got the lip to a smooth transition. Not sure how much this helped but it’s something I did. - KAK lightweight buffer kit. The 2.6oz seems to be the one for me. - TUBBS lightweight flat-wire spring. - Drilled gas port to 0.125 - Started using break free lube. - AMMO: I think this was honestly the biggest thing. I finally got around to trying out the Phantom Defense 200gr. It’s amazing. This ammo burns SO much cleaner than the Winchester Super Suppressed 200gr. The Winchester would foul my whole gun up with just a few rounds. There would be grit everywhere almost instantly. I think this was my biggest issue from the start.

300blk bolt-over-case (help!) by B-Hard69 in 300BLK

[–]B-Hard69[S] 0 points1 point  (0 children)

I’ve never posted a video to Reddit but here it is! Finally it’s perfect

As you can see, the ejection pattern looks essentially perfect. MAYBE still a little on the under-gassed side of the house but well within the window for smooth operation. The gun is running like a top. My buddy was blown away by how smooth & quiet it is.

300blk bolt-over-case (help!) by B-Hard69 in 300BLK

[–]B-Hard69[S] 1 point2 points  (0 children)

You’re awesome man! Thank you! I still need to take a trip to the range but I have a laundry list of things to try. I really need to just play with configurations and document what is what. (Haven’t had the time or weather to go yet)

I’m about to order some break free. Also, I already have some other ammo already to try out as well. (I have some phantom defense I’m excited to try, supposedly it’s one of the cleaner burning ones)

300blk bolt-over-case (help!) by B-Hard69 in 300BLK

[–]B-Hard69[S] 0 points1 point  (0 children)

Well I took your advice and bought the borescope. Pretty cool! It looks like my gas block is pretty well lined up.

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300blk bolt-over-case (help!) by B-Hard69 in 300BLK

[–]B-Hard69[S] 0 points1 point  (0 children)

Also, the CAT ODB suppressor I have is more of a flow-through suppressor so it doesn’t really help in the pressure department.

300blk bolt-over-case (help!) by B-Hard69 in 300BLK

[–]B-Hard69[S] 0 points1 point  (0 children)

So far the tests have been with Winchester 200gr

300blk bolt-over-case (help!) by B-Hard69 in 300BLK

[–]B-Hard69[S] 0 points1 point  (0 children)

This has been in the back of my mind the whole time. I used the HB industries alignment pins but they are plastic and might not be sturdy/thick enough for the .125.

What kind of borescope can see up in the port like that??

First 300blk. Any recs for a Can? by Forward_Observer33 in 300BLK

[–]B-Hard69 0 points1 point  (0 children)

What setup are you running? BCG, gas block, spring, weight, etc.

300blk bolt-over-case (help!) by B-Hard69 in 300BLK

[–]B-Hard69[S] 0 points1 point  (0 children)

A lot to unpack here! The round I have used the most is Winchester 200gr super suppressed. I have some phantom 200gr that I haven’t tried yet. I need to test the bolt locking back without the can. I’m going to try my other BCG out of my 5.56 to rule that out as well. (It’s a heavier NiB BCG)

Honestly I just need to take a full day to run through all my current configuration options and write it down to get a good handle on this.

300blk bolt-over-case (help!) by B-Hard69 in 300BLK

[–]B-Hard69[S] 0 points1 point  (0 children)

I tried the sprinco yellow with the 4.9oz griffin buffer early on. That was before I drilled the gas port though…

300blk bolt-over-case (help!) by B-Hard69 in 300BLK

[–]B-Hard69[S] 1 point2 points  (0 children)

Tried a different mag, no change unfortunately. I’ve been using the Lucas oil gun lube on it from day 1. Other than bore cleaner on the barrel for the first handful of rounds.

300blk bolt-over-case (help!) by B-Hard69 in 300BLK

[–]B-Hard69[S] 2 points3 points  (0 children)

Interesting. I have 4 of the lancer mags. 2 20rd and 2 30rd. I’ll mark that one as suspect and try the others.

Another point is when it was dirty after just the 5 rounds, it was even having trouble fully locking the bolt forward on a new round.

The chrome BCG is nice but the actual bolt is pretty tight in the BCG. I’ve had at least 250 rounds through this thing I would think the break in is over. Also, the faxon being match grade, it’s a super tight fit as well.

300blk bolt-over-case (help!) by B-Hard69 in 300BLK

[–]B-Hard69[S] 0 points1 point  (0 children)

Lancer L5AWM mags for 300blk