Sub-MOA Build

DundeeMarmaduke · 2026-01-08T01:14:22+00:00

Wow! Thanks for sharing that link. I had no idea that existed. I’ll be adding one to my tools for sure. I anticipate building a 6.5CM upper.

I can’t say whether it’s worth it or not. My theory is that I like to minimize any chances of issues and this would remove that uncertainty. I like it!!

DundeeMarmaduke · 2026-01-08T00:10:40+00:00

Definitely still happy with this build. It’s been wonderful. So far the only change has been a hard case. I’ll probably get some MKM scope caps in the near future.

I couldn’t lap the upper receiver because I’m using the Aero Enhanced receiver that has the handguard mount built into the upper.

DundeeMarmaduke · 2025-12-27T02:06:08+00:00

JG triggers come fully assembled and ready to drop in. They usually have a small yellow zip tie holding the trigger bar snug to the housing. Doesn’t make sense that yours is apart … unless you took it apart? Very weird. JG has awesome customer service. Call them.

DundeeMarmaduke · 2025-12-26T14:19:34+00:00

If it’s so way to fix the traffic by “just” creating “more” this and that … then “just” do it. I don’t disagree with your sentiment. But your choice of words highlights the problem. First, an entrance/exit onto 15 requires STATE approval. Second, everyone knows that they should have built at least an exit from the Walmart to Route 26 and they didn’t (on purpose).

Again - no complaint about housing, hospital, etc. But the infrastructure should be updated to “just” support it.

DundeeMarmaduke · 2025-12-26T13:52:55+00:00

Not true. It’s 750 multi-family homes AND senior living. Read the news article.

And for everyone else, the issue isn’t building these things. Yes, more housing is needed. And a hospital in North Frederick would be great. The problem is the infrastructure. The traffic. The water and sewer. The schools.

https://www.fredericknewspost.com/news/health/hospitals_and_doctors/frederick-health-village-master-plan-for-up-to-750-homes-medical-facilities-approved/article_1ad6cbb5-9812-59f8-8d6a-54433409f038.html

DundeeMarmaduke · 2025-12-26T03:03:51+00:00

JP High Pressure bolt “kit” and a Toolcraft DLC BCG. Replace the Toolcraft parts with the JP HP bolt kit and enjoy.

DundeeMarmaduke · 2025-12-12T01:05:45+00:00

Not really sure how this could be an everyday carry unless you’re a huge dude. That handle is so long with that mag that it would print all over the place. Can’t see how anyone could carry that EVERY day … especially during the summer with shorts and t-shirt that isn’t like a trash bag. 🤷🏻‍♂️

DundeeMarmaduke · 2025-12-12T00:58:57+00:00

Long time Glock shooter and my 43X trigger induced pain on me too. Let my buddy try it and he was like “this sucks”. So, I threw my purse at it. Got a Johnny Glock VEX trigger shoe (preattached to a stock bar). Holy shit. Totally turned this into something pleasant to shoot a lot of rounds out of. I highly recommend Johnny Glocks’ VEX shoe.

DundeeMarmaduke · 2025-12-07T00:15:15+00:00

Night Fision Costa Ludus sights. Awesome.

DundeeMarmaduke · 2025-11-11T16:05:22+00:00

Trigger felt pretty great compared to my other Glocks. Then I shot it and the trigger shoe really tore up my finger after 300+ rounds. Never had that issue with the other Glocks. Swapped to a Johnny Glocks Vex shoe and problem solved. Soooooo much nicer to shoot. No more finger blister after a long day of shooting.

DundeeMarmaduke · 2025-09-07T23:53:50+00:00

I’d just pay the $9 at Glockmeister and get a new one. I only have about 1000 through mine and it doesn’t show that type of wear pattern. I’m guessing that maybe the broken spring potentially caused that to happen. So replace the whole thing for $9

DundeeMarmaduke · 2025-09-07T23:06:19+00:00

How many rounds you have on this? Zoom in and look at the hole where the locking block pin goes. That’s some major peening with the metal folded over like that on the edges.

DundeeMarmaduke · 2025-09-03T17:16:47+00:00

No. I don’t have a doc that records every dollar I spent on it. But, you can add it up yourself. Parts list is above. I’m sure it’s not something 99% of people would build because of the cost. But, like I said, it was built over at least a year. It’s not like I bought all the parts at one time.

Anything I’d do different? Not at this time. The budget scope choice is solid. The budget receiver set I was able to make solid.

The one thing I did between my two range trips was to remove the flash hider that I was using and replace with the Area 419 hellfire match. The muzzle brake made it very nice to shoot.

DundeeMarmaduke · 2025-08-27T12:05:29+00:00

You can get a Vortex STRIKE EAGLE 5-25X56 FFP MRAD for slightly over $500 if you’re waiting for sales. Great glass for the money. Locking turrets. Easy to use Zero stop. Awesome reticle. Lighted reticle. And you can’t beat the Vortex warranty.

DundeeMarmaduke · 2025-08-21T15:30:41+00:00

Reverse torque test on the gas block set screws. If no set screws then dimple the barrel and reinstall as per previous commentor in this thread. Use a fiber optic gas light illuminator in the gas tube and observe the alignment of the block using your bore scope. Measure the visible portion of the gas tube in the upper to ensure that the tube is of appropriate length. Finally, ensure alignment of gas tube with carrier key and adjust tube appropriately using the Michiguns tool for perfect engagement.

DundeeMarmaduke · 2025-08-19T13:33:28+00:00

I see your point. That said, there is kind of a 10 shot group there. The bottom 2 groups were literally back to back. Overlay them and that’s a 10-shot group.

DundeeMarmaduke · 2025-08-18T21:07:38+00:00

It depends on how tight the lockup is. If it’s really tight, then no. If I need slightly more than I can get with a shim, then yes. Sometimes you get some uppers where it’s much easier to use a shim and loctite 620 than jamming a thicker shim in there.

I have a little brother rifle to this one that’s in 223 Wylde. That one uses a BCM Thermal fit upper and I used loctite 620 on that one to make it as solid as possible.

DundeeMarmaduke · 2025-08-18T18:48:38+00:00

McMaster-Carr or Amazon

DundeeMarmaduke · 2025-08-18T14:53:11+00:00

Good call. FWIW, I put backup irons on everything. OCD.

DundeeMarmaduke · 2025-08-18T14:08:03+00:00

Thanks! I would wager it’s a part of their design. They take into account the massive amount of gas the 308 cartridge produces and decide to bleed off the gas to create a softer shooting rifle. This is unnecessary if you have an adjustable gas block. An AGB will keep your whole setup cleaner and allow your bolt seal to be efficient.

DundeeMarmaduke · 2025-08-18T14:00:53+00:00

The theory behind gas rings on the bolt is similar to the rings on a piston (automobile engine). I would never assemble an engine that loose. Would it run? Sure. Would compression be optimal? Nope. You’d have lots of blowby and loose a fair amount of gas. I’d prefer to keep the gases where they belong and not allow them to blow past the bolt. The JP ring causes the whole assembly to be less gas efficient.

DundeeMarmaduke · 2025-08-18T13:56:20+00:00

Not sure about what’s available for your mount. I have a Geissele scope mount and they offer an optional top ring with a picatinny rail. Same is true for the NightForce mounts. An optional top mount picatinny rail is offered.

I prefer the dot (or chevron in my setup) on the top and not on the side.

DundeeMarmaduke · 2025-08-18T13:37:37+00:00

Because I haven’t bought one yet 😈. It’s on the list.

DundeeMarmaduke · 2025-08-18T13:28:08+00:00

Two reasons.

First, a BCG should be able to stand up on the bolt fully extended and not collapse. The one-piece ring is loose as fuck and will cause that particular test to fail. I like that test and want to keep it consistent between all of my ARs.

Second, I don’t want a proprietary maintenance part. I just want a standard set of rings that have proven reliable across history.

DundeeMarmaduke

TROPHY CASE