gdonley308

Thanks guys!! Who needs gunsmith’s when we can figure it out.

UPDATE:! I got back from work 05/30. First I want to thank the members of this board for their help. I bought a $0.48 8-32 Allen screw and cleaned up the gas block threads with a tap. I then followed Armalites instructions and screwed the gas adjustment all the way in, then backed it out 2 1/2 turns. At that setting the rifle ran perfect! No FTE, no hiccups of any kind with both Federal 168gr Gold Metal Match and UMC 150gr FMJ. Yep, the rifle was over gassed, even has less recoil as well. This is 10rds of the Federal GM at 100yrds. The other rounds are 5.56 from an iron sight 6920.

Yes, absolutely correct. I have over 4yrs machinist background and know how stainless can gall. I have sourced some ARP grade 8 steel set screws. I’ll be using these for my gas block. I’m at work in Texas for the next 3 weeks. I’m looking forward to getting home and tuning the gas system! I’m happy to here this is an easy fix, with the rifle being over gassed.

This is a factory new rifle. From what everyone on here is saying, it seems over gassed. This would coincide with Armalite’s litterateur that says the rifle ships with the gas block adjusted wide open. I’m going to buy another Allen screw for adjustment and another for locking. Armalite says for tuning, screw in the adjustment all the way then back out 3 turns. Conduct the one round function test. Adjust until the bolt just locks back, then back off another 1/4 turn and lock in place. I will relieve the one hole in the hand guard to give clear access to the adjustment screw.

Well, you people are very helpful!! I have decided, when I get Home, to chase the threads in the adjustment port, buy a new adjustment screw and a locking screw. Then I’ll go through the steps Armalite recommends for tuning. Screw the gas regulation screw all the way in then back it off 3 turns. I’ll use the Federal 168gr Gold Match to tune it with. The reason I wanted a front mount adjustment screw was because the factory screw wasn’t directly accessible through the KeyMod hand hard. Decided I’ll just relieve that one hole in the hand hard slightly to allow a good straight access to the screw. From the general consensus here, seems like an over gassed issue.

Yes, shone a light through and put a small screw driver through the locking screw hole until I could see it in the adjustment hole

Ok, I’ll hold off on polishing. Could my extractor be out of spec? Ejector spring too strong? Buffer too light? Things definitely got worse with the Springco Extractor Springs. I have to go to work in Texas for the next 3 weeks so it’s going to be awhile before I get to shoot the rifle again. Can over gassing cause these FTE? Armalite states in their litterateur that the gas block is adjusted for full gas from the factory. Some people are telling me to throw in an H3 buffer? I run H3’s and Tubbs buffer springs on my 6.8spc’s for a 3 o’clocK Ejection pattern with 110-115gr loads.

Nope, nothing in that hole but threads.

Here’s where the locking screw should have been

I haven’t paid for it yet. I want a forward adjustment on the next gas block, one that won’t work loose. What gas block would you recommend?

LINk to the new gasblock https://suparms.com/collections/adjustable-gas-blocks-direct-impingement/products/875-adjustable-gas-block-bleed-off-solid-melonited

I’m going to replace the gas block with a Superlative Arms .875” Bleed Off adjustable gas block. It costs $85 which, if Armalite ever answers me, is what it will cost me to ship it to them and back. Going to also polish the chamber although the brass looks fine, and go back to the factory extractor spring. Should I buy a “Go-No Go” gauge and check the chamber before polishing? This one has me baffled. Of all my AR’s including my 6.8spc’s this is my first problem child.

Yes I see that! Here’s some pics

No, just the one stripped Allen screw you see in the picture. No adjustment screw, or if this is the adjustment screw there was no locking screw? Either way, it took allot of heat ( most likely red loctite) and the screw is stripped. No answer to numerous emails and phone calls to Armalite?

I have that rifle in 6.8spc. Has been flawless!

First off I want to thank you and everyone else trying to help me diagnose this issue! Here’s the pictures. I included the Armalite litterateur for the adjustable gas block. There was no locking Allen screw, just the one shown. Even with allot of heat, threads were destroyed. Not happy about a new , relatively expensive, rifle coming through QC like this. As you can see, it happened with a variety of ammo. It also got worse with the Springco Dual extra power extractor Springs.

I searched but didn’t find any topics covering this. I have an Armalite TAC18 in .308. I’ve been having FTE now very often. This rifle came with an adjustable gas block. I upgraded the extractor spring to the Springco extra power dual spring set up. This did not help. Now I’ve been reading that an over gassed rifle can have FTE? With this in mind I took off the handgard and tried to adjust the gas. The Allen head screw for the gas regulation was almost impossible to get out. I used heat and finally got it out. There was no locking screw as described in Armalites leaflet that came in the manual for the adjustable gas block. Has anyone heard of an over gassed rifle having failure to Extract? Stock photo shows the rifle in question. Thanks

I have previously posted about my Armalite TAC18. I had to head off to work, so it will be 3 weeks before I’m at the range again. Apparently they didn’t build allot of the TAC18’s. Back in November I purchased a Armalite KTC (Light Tactical Carbine) in 6.8mm SPC. Armalite said they built very few of these rifles as well. The specs are great and it weighed in at 6.3lbs. 6.8spc is my favorite chambering for a standard size/weight AR. With everyone’s favorite flavor being the .300Blk I think the 6.8spc is overlooked. I have been a fan every since the advent of the Spec II chamber. Group is iron sighted offhanded work from 50yrds

Thanks, It seems the cheapest first step and as you said, logical. I contacted Armalite, they assured me the chambers are finished polished, it looks it too. They’re sending me a new factory spring as well but I’m going with the Springco spring anyway.

No it happened with both the 10rd Hexmag and the 20rd PMag? I’ve ordered a extra power extractor spring from Springco and a David Tubb SS flat wire buffer spring. The Tuub’s Springs I put in every AR I own including my two 6.8mm AR’s. The have a 500,000 round device life. The military adopted them too. Rifle will be long wore out before the buffer spring. The also increase lock time. My ejection pattern was a perfect 4 o’clock at 8’ with both the Federal and LC, so I don’t think it’s over gassed?

Thank you.

Yes, fully stripped and cleaned before firing. BCG and Upper heavily lubed (wet) with EWL.

So great to be here! Love the 6.8mm SPC too!

Hi, and thank you for being here. I took the Armalite to the range today for a 100yrd accuracy test. I previously fired 160rds of LC NATO breaking the rifle in and rough sighting at 25yrds. I had zero malfunctions. Today I was having FTE on every other magazine. Most of the time on the first round chambered by dropping the bolt, but then it happened twice half way through the magazine. I am using PMags and a 10rd Hexmag. Put another 100rds through the rifle had 5 FTE. Could the chamber be dirty that quickly? Could the extractor spring gotten weak that fast? I stripped the rifle down and thoroughly cleaned everything. Everything looked good and fresh ammo dropped in and out of the chamber, no problem. Hand cycling resulted in no problem either. I’ve attached the Armalite specs for the rifle, it does have an adjustable gas block. Accuracy at 100yrds with the LC NATO 149gr ball was pretty good. A tactical workhorse, the AR10TAC18 is the perfect tool for duty and defense. All Armalite Tactical Series rifles come equipped with MAGPUL MBUS flip-up sights and MOE+ pistol grips. The dual-purpose flash hiding compensator tames recoil while reducing signature. The sturdy 15″ tactical Key-Mod handguard provides ample hand placement and a full-length MIL-STD 1913 12 o’clock rail for sights an accessories. An adjustable gas block also allows the rifle to be individually tuned for optimal performance for your choice of ammunition and/or suppressor use.