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November 29, 2018, 07:08 PM | #1 |
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How would you correct an over gassed AR ?
I recently inherited my dads AR . It"s 16" mid length 223 Wylde from PSA with a standard carbine buffer and spring . It's always been over gassed since we put it together 3 years ago . It ejects the brass to the 1:30 position and today I tried a H1 buffer in it but that only changed the ejection to the 2:30 position . An H2 will likely fix the issue but is that the best way to fix the problem ?
For the most part my uppers and lowers are dedicated sets to each other but I do from time to time mix and match . All my personal AR's eject to the 4:00 position pretty much stacking the brass in little piles . I can add the H2 buffer and just call his rifle a set not to be messed with because that lower with a H2 buffer will likely not work well with some of my other uppers . Or I can install an adjustable gas block on the upper allowing it to be gassed the same as the rest of my uppers . What do you guys do who have multiple uppers and lowers that need proprietary items that allow them to operate best ? Do you dedicate each upper to a lower as sets or try to get them all gassed the same so mix and match is not an issue ?
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November 29, 2018, 07:38 PM | #2 |
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I assume that your Gas Block is non adjustable?
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November 29, 2018, 08:19 PM | #3 |
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Mine have dedicated lowers. Adjustable should fix it.
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November 29, 2018, 08:21 PM | #4 |
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With mtpl uppers being switched onto a lower, the buffer is not the place to adjust stuff. Put an adj gas block on the upper and tune that.
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November 29, 2018, 08:27 PM | #5 |
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If my guns are reliable and accurate I could give a rip where they eject.
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November 29, 2018, 08:33 PM | #6 |
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Change the gas block out to an adjustable one.
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November 29, 2018, 09:41 PM | #7 | |
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Quote:
https://palmettostatearmory.com/9mm-...ffer-assy.html
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November 29, 2018, 09:44 PM | #8 | |
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Quote:
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November 29, 2018, 10:08 PM | #9 |
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Changing buffers and springs is not fixing overgassing, just a band-aid.
If you reload, use a faster powder or drop the charge weight. Otherwise, the only way to do it is to reduce the amount of gas that goes into the gas key. That mostly means putting on an adjustable, or switchable gas block. That increases maintenance, some more that others. I use Superlative Arms gas blocks on the 3 I have that needed adjustable gas. |
November 30, 2018, 01:43 AM | #10 | |
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Quote:
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November 30, 2018, 10:05 AM | #11 |
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By the way, they also make adjustable gas keys now as well.
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November 30, 2018, 11:58 AM | #12 |
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Adjustable gas keys will tune the recoil impulse, but they do not correct all overgassing issues and run dirtier than controlling the gas at the block or port.
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November 30, 2018, 12:46 PM | #13 | ||
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Quote:
Quote:
Am I wrong in assuming an adjustable gas key would need to bleed off the gas ? where does that bleed off to/at ? Is there an actual good reason to have such a thing rather then fixing an issue the traditional ways ? I asked the question like that because I see no reason to even invent such a thing but leave open possibility there are fantastic uses for an adjustable gas key .
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November 30, 2018, 01:07 PM | #14 |
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The primary use for an adjustable gas key is competition. You run your hoser load which is 55s at 2600 to 2800 fps. Nice and soft and flat, tuned to go fast and not overgassed so the adjustable gas key is not bleeding off much of anything. Then with the 69 to 77 grain load at 2800 to 2900 fps, the excess gas is dumped (yes into the action) but the gun behaves and recoils substantially similar to the hoser load. So unless you are running mostly a short range low powered load with some longer range precision loads like is done in 3Gun, there is absolutely no benefit to an adjustable gas key. I keep 3 or 4 3Gun ARs running with close to 20K through them annually and still won't use the adjustable gas key. But shooting PRS as well, I focus on the long range a lot more and I don't see any benefit in them for how I shoot.
Most avid 3Gunners are, over the next month or two, stockpiling ammo and rebuilding their guns. Run 10K and rebarrel, some go with a new bolt, and replace all the wear parts. |
November 30, 2018, 01:15 PM | #15 |
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Well, technically, your bolt is already adjusting gas pressure by blowing the excess gas out the two holes in the side of the carrier once the gas rings are pushed back far enough.
So, the adjustable gas key isn’t directing more gas into your upper. It is directing the same amount of gas and diverting some of it through the gas tube cloverleaf and the rest through the ejection port. If you take the view that most fouling in the AR systen is related to the bolt unlocking early with residual pressure still in the bore, then anything that delays the unlocking will reduce fouling; and bleeding off gas before it enters the expansion chamber in the carrier will delay unlocking. An adjustable gas key is also easier to retrofit then pulling off a gas block or swapping to a barrel with the correct port size/no erosion for your use (which is what all the other solutions, including adjustable gas blocks, are patching). If you’ve got an adjustable gas block handy and you are comfortable swapping them out, I’d go that route. But for the guy who doesn’t want to dremel off his pinned front sight base, the adjustable gas key gives you options. On my personal rifles, I just increase buffer weight; but I’m not swapping uppers and lowers around either. |
November 30, 2018, 05:15 PM | #16 |
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Typical suggestions to include heavier buffer. On a PSA, which ever is cheapest and easiest; the buffer.
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December 1, 2018, 10:20 AM | #17 |
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have you noticed any copper fouling in or around your bcg?
i'd be concerned about the size of your gas hole in the barrel. i've found the larger the hole the more over gassed and you will see alot of copper stuck in the gas block. |
December 1, 2018, 10:56 AM | #18 |
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One thing that can help is to go to the heaviest recoil spring and heaviest buffer you can get. This will not fix a grossly over-sized port, but when you are about 20-25 percent over-gasses it works very well and also help with brass life. Brass life is not a consideration if you don't reload your own ammo however.
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December 1, 2018, 11:29 AM | #19 | |
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I do reload and although I have a lot of brass . Brass life is still something I want to extend .
The rifle is new to me so I don't know if it's getting more copper fouling . I've not shot it enough . In fact I only have about 100rds if that through it since I got it a couple months ago . I'm going to put the Seekins gas block on it this weekend and shoot on the tenth . On a side note : Quote:
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If Jesus had a gun , he'd probably still be alive ! I almost always write my posts regardless of content in a jovial manor and intent . If that's not how you took it , please try again . |
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December 1, 2018, 11:50 AM | #20 |
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i pull mine apart and put it in my ultra sonic cleaner with berrymans carb and parts cleaner
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December 1, 2018, 12:15 PM | #21 | |
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Quote:
I have a few with Melonite or QPQ bolts and barrels, and that is a wipe down at 1K and keep on going until about 10K when I do the above. |
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December 1, 2018, 12:40 PM | #22 |
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It was probably considered cheating, but on one rifle I thought was over-gassing I just used a bore scope to watch the holes and I eased the gas block forward slightly. I only "off-centered" the holes by maybe 1/8 to 1/4 of the hole width, but it was enough.
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December 1, 2018, 01:01 PM | #23 |
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I was going to ask sometime soon here at TFL how often any of you clean your gas tubes and how would you do that.
I've got some ARs that are almost 30 years old and I've never cleaned the gas tube in any of my ARs. Last edited by ed308; December 2, 2018 at 12:47 PM. |
December 1, 2018, 03:12 PM | #24 |
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Personally, I've not seen an over-gassed mid-length 16". Guess I'm missing something.
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December 1, 2018, 04:53 PM | #25 |
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My DPMS was wildly overgassed and tearing up brass to the point it wouldn't go in shell holder. An adjustable gas block solved all the problems.
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