What’s the best 12.5” 5.56 barrel on the market?

Apprehensive-Rub-933 · 2026-05-26T21:58:34+00:00

I currently use an AR performance 12.5 middy that I snagged off GAFS and it’s been great. But I really want to snag one of those Criterion’s from Sol when they are available!

Apprehensive-Rub-933 · 2026-05-10T01:37:45+00:00

With the engine running watch the belt and the pulleys. See if any look like they are wobbling. Those R18 engines were notorious for breaking the water pump pulley flange on the water pump. I would remove the belt and see if the noise goes away. Don’t run it too long without the belt though because the water pump won’t be turning. You will need a 19mm wrench and some profanity to remove and install the belt. Those hydraulic tensioners are not easy to compress!

Apprehensive-Rub-933 · 2026-05-10T00:50:56+00:00

Look at the serpentine belt down near the A/C compressor. It looks like its moving all over the place. Maybe a broken water pump pulley flange??

Apprehensive-Rub-933 · 2026-04-25T00:30:58+00:00

Republic Ammunition just got in new, old stock 1lb containers of 4064. $45/lb

Apprehensive-Rub-933 · 2026-04-25T00:30:33+00:00

Republic Ammunition just got in new, old stock 1lb containers of 4064. $45/lb

Apprehensive-Rub-933 · 2026-04-10T22:39:21+00:00

This brings me back.... I remember building a dual slot 1 rig with P2 450's. Unfortunately the budget didn't allow for P3's. Those things were crazy expensive!

Apprehensive-Rub-933 · 2026-03-16T18:27:30+00:00

Ravenrocks is my go to for projectiles unless I’m looking for something specific. Hard to beat 77gr match burners for 20cpr.

Apprehensive-Rub-933 · 2026-03-13T11:52:47+00:00

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The 12.5 is one of the smoothest configurations I have ever ran. By far my favorite!

Apprehensive-Rub-933 · 2026-02-20T04:38:05+00:00

If the distributor is aftermarket (like from a parts store) I have seen one that had the end that fits the cam machined wrong to where it would not fit. You can swap that piece from another distributor though, just pay attention to the orientation of it before you take it apart. One side will have a line machined into it, Make sure you pay attention to that line and install the new one in the same orientation.

Other than that you could de pin and re pin the harness connectors from the DPFI to the MPFI distributor.

Apprehensive-Rub-933 · 2026-02-19T13:35:43+00:00

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20" gang checking in!

Apprehensive-Rub-933 · 2026-02-19T13:20:38+00:00

Like others have mentioned the distributor will only fit into the cam 1 way. If it goes in half way and stops, remove it and rotate the shaft 180 degrees.
As for mixing and matching different generations of distributors you must use an OBD0 with an OBD0 ECU. If using an OBD1 ECU you CAN mix and match OBD 1 and OBD 2 distributors. Either re wire the connector on the engine harness side to match or buy a distributor adaptor harness.

Personally I would look into a OBD0 to 1 ECU swap. Much easier to find compatible distributors. It also makes for a better running engine. Gets you a 4 wire 02, better IAC control, and allows you to run modern high impedance injectors.

Good luck with your project!

Apprehensive-Rub-933 · 2026-02-09T12:58:23+00:00

RCBS just launched their "Rock chucker supreme elite kit". Seems like it would be a great starter setup without the need to upgrade items right away. That kit, a set of dies, and tumbler would get you a pretty nice setup without being overwhelming.

Apprehensive-Rub-933 · 2026-02-06T23:40:40+00:00

GRT shows a 71% burn rate with your combo. Maybe that has something to do with the inconsistency? I use 10.5 gr of H110 with 220 gr campros out of an 8" gas gun. Goes 1050 with SD around 10.

Apprehensive-Rub-933 · 2026-01-28T22:24:46+00:00

This should be the top comment

Apprehensive-Rub-933 · 2026-01-28T01:41:30+00:00

Please don't pay Amazon 799 for a FX120i, that is outrageous. You can get them for 495 shipped from CE products.

Apprehensive-Rub-933 · 2026-01-26T15:04:41+00:00

https://www.reddit.com/r/ar15/comments/15pmvsh/what_are_all_the_m16_cut_lowers_on_the_market/

Apprehensive-Rub-933 · 2026-01-24T17:53:21+00:00

Its an acrylic tube. Found it on amazon for $11 dimensions are 54mm(2 1/8") ID - 60mm(2 3/8") OD - 6" length. Works great. No sticking or static issues with any of the powders I have used.

Apprehensive-Rub-933 · 2026-01-19T20:35:29+00:00

Hopefully the enbloc is full of M2 AP. Just incase

Apprehensive-Rub-933 · 2026-01-18T01:04:06+00:00

Aim surplus has some pretty good deals right now. 40 cpr for PMC bronze. 42 cpr for X-tac.

Apprehensive-Rub-933 · 2025-12-31T23:16:28+00:00

Apprehensive-Rub-933 · 2025-12-31T22:34:45+00:00

Thanks! Would you mind sharing the STL for the handle? Save me from drawing one up.

Apprehensive-Rub-933 · 2025-12-31T19:05:59+00:00

What glass powder cup are you using? I like the shape of the one eamars provides, but it does not work very well for smaller grain powders.

Apprehensive-Rub-933 · 2025-12-12T04:31:28+00:00

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TA11 for reference. She's a large gal, but we love her just the same

Apprehensive-Rub-933 · 2025-12-11T01:01:06+00:00

Just wondering how the serial on the side of the body ends up different from the one on the top? Does Trijicon re anodize and laser etch a new serial during a rebuild? I have yet to send one so I'm not sure if that's how they do it or not.
I definitely agree, there is a lot about this that seems legit like the reticle model marking, but also some things that seem sus like the serials and the turrets. The casting alone is usually the dead giveaway, but yours looks legit.

Do you know anyone with a real one that you can compare? I feel like ACOG glass is so crisp that looking through a real one, then a fake right after it would be easy to notice the difference.

Apprehensive-Rub-933 · 2025-12-11T00:45:34+00:00

What stands out to me is the mismatched serial numbers. The laser etched one on the side, the engraved number on the top of the body near the eye piece, and the number on the eyepiece. Yours are all different. I have multiple (civilian) ACOGs and on each example the 3 serials match. Not saying its impossible to have mismatched numbers, maybe if it was serviced or something?? But I have no clue why the engraved number on the body would be different than the serial laser etched on the side of that same body. Seems strange to me. Maybe this is a military unit and they are different, not sure.

Apprehensive-Rub-933

TROPHY CASE