AR-15 Gas and Recoil Tuning

[Saltyag2010]

I know my AR is over gassed. I'd rather have it that way than under gassed, but I would like to understand how to tune an AR-15 gas and recoil system.

I would like to know how to tune 2 different uppers on the same lower. Uppers - midlegth gas (#1) and carbine gas (#2) Lower - Carbine Mil-spec lower with standard buffer and spring.

If I wanted to tune the gas systems which block or blocks would be best for upper #1 and #2?

For the buffer system- what buffer weights should I get to try and what springs if any do I need to try?

Please explain tuning and how to tell if I can use a heavier buffer or when I need to go to a lighter buffer. Are there any other tricks?

Thanks

 

[Mexican_Hippie]

Heard these are good.

http://www.jprifles.com/buy.php?item=JPSCS-15

 

[Saltyag2010]

Heard these are good.

JP Rifles

Are they tune-able with different weights or springs?

 

[Das Jared]

What brand of barrels are you running? Your best bet is a syrac adj. Gas block. I personally run a BCM gas block and h3 buffer. My rifle is overgassed when ran suppressed only.

sent from jennifer lawrence's bedroom

 

[Saltyag2010]

Voodoo and PSA. 1/7 and 1/9

Edit- does the barrel manufacturer really make a difference on the gas coming into the chamber?

 

[Saltyag2010]

What brand of barrels are you running? Your best bet is a syrac adj. Gas block. I personally run a BCM gas block and h3 buffer. My rifle is overgassed when ran suppressed only.

sent from jennifer lawrence's bedroom

Links?

 

[Das Jared]

Voodoo and PSA. 1/7 and 1/9

Edit- does the barrel manufacturer really make a difference on the gas coming into the chamber?

Different Manufacturers have varying degrees of quality when drilling gas ports in barrels. BCM, Rainier Arms, Wilson Combat, Battle Arms Development, and a couple of others I can't think of will be your best bet

sent from jennifer lawrence's bedroom

 

[AaronP220]

What's your barrel length and gas system length.

Running an adjustable gas block is your best bet. That will allow you to run the lightest buffer and BCG to get the least recoil / shot impulse possible.

For gas blocks that are adjustable there's only one worth buying. Syrac (no, I don't get free shit to say that). The reason I say use Syrac is most adjustable gas blocks require you to tune your system, pull the adjustment screw and put loktite on it and then get it back into the same position. It's a bad way to do things. The Syrac adjustment screw is click detended for ever 90 degrees of rotation. Set your gas system for unsuppressed and you're good to go.

MOST ARs require the gas system to be turned WAY down. With an adjustable gas block there's ZERO need to get into the different buffers and spring weights. Simply run a std carbine buffer spring and buffer and you'll be good to go. With the standard gas block there's now way to effectively tune the system. You're still sending the same amount of gas to the BCG and just throwing weight into the system to slow it down. But it only works on recoil impulse. Your bolt is still taking a massive hit because you're unlocking too early and other things are going on that aren't favorable to AR operation. When you can actually TURN THE GAS DOWN you get less bolt pressure and speeds, less gas into the upper system so you run cooler and cleaner and you get less recoil with a more reliable system.

So, I don't think the direction you need to go is messing with buffers and spring rates. Swap your gas block for a Syrac (or I can do it for you) and actually tune the system. The $100 upgrade is one of the absolute BEST things you can do for your AR.

 

[AaronP220]

FWIW - I run a Lantac E-BCG (yes, it does matter), Syrac gas block, H1 buffer, JP polished spring and Dragon brake. That system is one of the flattest, softest and low impulse systems I've ever seen.

The Lantac E-BCG is different than a std BCG. (You BCG effects the gas system too)

 

[Saltyag2010]

Aaron,
Thanks. Is this video accurate- [video]https://m.youtube.com/watch?v=evnB_C3U-Uc[/video]

 

[Saltyag2010]

Bcg- Lantac Enhanced Bolt Carrier Group - E-BCG - Primary Arms

JP Enterprises Syrac Adjustable Gas Blocks near bottom of page- https://www.primaryarms.com/Adjustable_Gas_Blocks_s/5098.htm

JP Buffer Spring- https://www.primaryarms.com/JP_Tuned_and_Polished_Extra_Power_Carbine_Buffer_p/jp-osc.htm

T1 Spikes Buffer- https://www.primaryarms.com/Spike_s_ST_T1_Tungsten_Heavy_Buffer_3_0oz_p/sla00t1.htm

So are these parts a major upgrade?

 

[AaronP220]

Yes - that video is accurate on how to adjust the system.

Depending on what you're running now you can probably get away with just the gas block and see a major improvement in the over all system, especially if you polish things in the BCG recoil path to help reduce friction.

The major advantage to an adjustable block is you can start running even lighter than regular carbine stuff. The Lantac E-BCG is actually heavier than the standard carbine BCG. The thing I like about the Lantac is the gas ejection ports for the bolt on the carrier are facing forward- which blow the gas away from the direction of travel helping reduce recoil and keep gas out of your face. If you really wanted to take advantage of the adjustable block you could get a Young Ultra-Light BCG with a lighter than carbine spec buffer and I would bet that system would be even flatter and lighter than my current set up.

I also do things to help the recoil system cycle. I polish the JP polished spring even more. I also polish the inside of my receiver extension and my upper channel where the BCG and cam pin rides (The Lantac domed cam pin is really sweet, too). So the reduction of friction in my recoil system mandates less gas as well because the system is moving easier.

Here are some weights - Buffer
Carbine (That Spikes T1) - 3.0oz
Heavy H - 3.8oz
H2 - 4.7oz
H3 - 5.6oz

BCG
Lantac - 11.7oz
M16 - 11.3oz
Young N/M - 10.5oz
Young SuperLight - 9.2oz

So, in theory a Carbine, or lighter buffer, with a Young SuperLight BCG with a tuned gas system would give you the flattest and least recoil impulse. I believe the Lantac had advantages over the lighter BCG's in their design and application so that's what I now like to run in all my ARs. For what it's worth I ran the Young N/M for years up until Lantac talked me into trying their E-BCG.

So if you want to keep it cheap just do the gas block. That's the beauty of it. You can tune it to match your current system. Or you can do it all or any variation of it. I think if you polish the areas and do the gas block you'll have a significant improvement with minimal cost.

Here's a cool Lantac video. At the end of the video you can see how the E-BCG blasts the gases forward.
[video] [/video]

 

[cajunautoxer]

I didn't have a chance to read all post. I'd use JP stuff and can't go wrong. I have over 10k rnds thru my 3G rifle no issues. Stay away from syrac. Their customer service sucks balls from what I've read. The bcg with adjustments on it is nice but imo to new to use yet.
If you want to just use adjustable GB it will make a difference. Now if you want to go with low mass bcg you don't have to buy a different buffer. Just take the weights out and you gtg.

Now as far as low mass bcg goes. While reducing weight is the goal the manufacturer also needs to reinforce some areas from what I've read. Their have been some cases of low mass bcg breaking. I haven't read about this is JP bcg

 

[Saltyag2010]

Ok. I think my next upper I'll do the adjustable gas block and that bcg and buffer spring. Looking and reading about the bcg made me a believer.

Would it it be even smoother with an A2 buffer system?

 

[AaronP220]

Soooo....reading that few people (out of the likely many thousands sold) that had a bad experience with CS (and who knows the truth there. This company wouldn't give me my money back because I didn't know what I was doing and was a rude ass to them so **** them... kind of stuff) is enough to stay away from Syrac, not because of issues with the product based off of your experiences or experiences of people that have put thousands of rounds through them, but because people had issues with CS. But you praise JP...and JP joined with Syrac to make the gas block we're talking about. Interesting.

 

[AaronP220]

Ok. I think my next upper I'll do the adjustable gas block and that bcg and buffer spring. Looking and reading about the bcg made me a believer.

Would it it be even smoother with an A2 buffer system?

A2 buffer weights are somewhere over 5oz.

 

[Saltyag2010]

A2 buffer weights are somewhere over 5oz.

They are physically bigger but I read on another forum that it was lighter because it was designed for a rifle length gas system that had less recoil so it was lighter than a carbine buffer.

So if it is heavier, how would it run in an adjustable gas block? Does the added length have any effect of recoil?

i couldn't find the syrac in stock, but a site sponsor had the JP Syrac in stock. How many adjustments do these blocks have?

 

[cajunautoxer]

Aaron 220 why are trolling me? Is it bc I called out your booty buddy and made him look like the bitch he is?

 

[Saltyag2010]

Aaron 220 why are trolling me? Is it bc I called out your booty buddy and made him look like the bitch he is?

No one is trolling you on this thread.


GET OFF THIS THREAD. THIS IS FOR GUNSMITHING ADVICE ONLY.

 

[cajunautoxer]

My bad. FYI there are companies that have barrels that you can use regular gas blocks and run low mass bcg to bypass the issue of a adjustable GB going bad. I'm sure Aaron can tell you who they are