Tubb Spring

[KTAK]

Some might say heresy but I am not enamored with the Tubb recoil spring

Had some ejection issues with my LR308, basically the bolt was moving too fast and occasionally holding onto a case, so time to slow it down. And I like things simple so an adjustable gas block is not an option

Aero 18" Barrel, rifle gas system, fixed gas block, Aero BCG
A5 buffer tube, originally running an H3 buffer
Running a clipped rifle length recoil spring, cut down to carbine length

Shooting mostly 150 grain handloads that are pushing 2800 fps and some downloaded 180's doing about 1700 fps. (The slow 180's are a good 200 yard bullet that are just fun to shoot.)

I have a fair amount of experience working with buffers and clipped springs in small frame AR's so this was the route I chose for my large frame

First thing I did was get a XH buffer from Heavy Buffers.com, hats off to Clint for getting it to me in two days.... (For those that may not know this is an 8.5 ounce carbine buffer)

Also ordered the Tubb recoil spring since it is mentioned here a lot

Since the buffer showed up first, threw it in with my clipped rifle spring and the ejection issue was solved. Recoil had a decent feel to it as well.

Today got a chance to include the Tubb spring into the mix... Definitely easier to rack the charging handle, which is nice for pulling the bolt back but not a good sign for slowing the bolt down.

Range time. Basically with the Tubb spring the buffer is slamming into the bottom/back of the buffer tube, something that did not happen with my clipped rifle spring. (I can feel a sharp rap right before the bolt starts back into battery) Also thought there might be a problem cycling the softly loaded 180's but no issues, the bolt still locks back on an empty mag. Softly loaded rounds that still will lock back indicates a soft recoil spring.... with the original set up in the rifle the 180's would not lock back on an empty mag....

Next step is to make a better comparison between the clipped spring and the Tubb spring and see if the 180's will lock back on an empty mag with the clipped rifle spring.

I know you guys with adjustable gas blocks can just turn a screw but I am having fun messing with this thing and isn't that the point.....

 

[bfoosh006]

Interesting results. Are you sure you got the .308 Tubbs and not the 5.56 Tubbs ?

I have some spares at home and if you'd like, I could measure both... ( I have never checked to see if there is a length difference )

I have been very happy with all my Tubbs, so happy, I use them in all my AR's

 

[Lawless]

It could be happening as the Tubbs has less pressure with the bolt to the rear than a standard spring (but more when the bolt is in battery).

You saying pulling the charging handle is easier makes me suspect as well, like @bfoosh006 that this may be an AR15 spring. I can tell a difference between the two springs in my 6.5C with the Tubbs being slightly more difficult to manually unlock the bolt when initially pulling the CH rearward.

In my opinion, any large frame AR needs adjustable gas.

The new Strike Industries finger adjustable block is nice.

Collar Adjustable Gas Block

Traditional adjustable AR gas blocks often require tools to adjust the settings. On top of that, going back to the same settings can be difficult like when switching from suppressed and unsuppressed configurations. Remove the hassle but keep the functionality with Strike Industries’ innovative...

www.strikeindustries.com

 

[kenny1773]

I have mixed experience with Tubbs flat wires. I love the one I put in my AR15, works great

However, the one I got for my AR10 never worked properly in that gun no matter what I tried.

I never compared them to see if maybe they sent the wrong spring for the AR10, but I know 100% I ordered an AR10 spring.

I eneded up going with a Spingco red and am very happy with it.

I also agree the adjustable gas block is a must in a large frame AR, I like the superlative one

Adjustable Gas Blocks - Direct Impingement - Bleed Off

with our Patented "Bleed Off" for the AR-15/AR-10/LR-308

suparms.com

 

[KTAK]

Unless Tubbs mismarked the package I definitely got the 308 Spring. The Tubbs spring I tried is much heavier than my small frame set ups (all carbines so no rifle AR15 to compare) and it is heavier to pull back than a 308 Carbine spring that I also have tried in my rifle.

If it means anything to you guys this Tubbs spring is just shy of 20 inches long and has 47 coils including the ends, package is marked SR25/AR10

My clipped DPMS rifle spring works great with the XH buffer, no real need for the adjustable gas block as it cycles rounds and locks back on empty mags every time using the fixed gas block that came on my upper. I can see the need for the adjustable block if you wanted to run a lighter buffer and spring set up. The XH buffer cured my ejection issue as well (occasionally stovepiping spent cases)

Clipping recoil springs to tune the system is a lot like turning the screw on an adjustable gas block, I just can't undo it if I cut off too much, LOL

 

[TonyTheTiger]

Clipping recoil springs to tune the system is a lot like turning the screw on an adjustable gas block, I just can't undo it if I cut off too much, LOL

Wouldn't shortening a spring be roughly equivalent to opening a gas block? AGB's are used to get less gas, not more.
You said you like things simple, your method sounds like the opposite of simple though.

 

[KTAK]

Wouldn't shortening a spring be roughly equivalent to opening a gas block? AGB's are used to get less gas, not more.
You said you like things simple, your method sounds like the opposite of simple though.

Yes and No, clipping springs has to be done in conjunction with the buffer weight. Using the spring tension and the buffer to balance the system much like an AGB does but instead of the gas I do it with the weight of the buffer and the spring tension. I learned to do this when I was having a bolt bounce issue on a Blackout. Increased the buffer weight to stop the bounce and clipped the spring to balance the cycling, giving me a gun that will cycle subs, supers, suppressed and unsuppressed with no changes needed when switching between rounds. That rifle has functioned this way for over 10k worth of rounds.

When I originally built up my 308 rifle I used a full length DPMS rifle spring with an H3 buffer in an A5 length tube, pulling the charge handle seemed way too stiff plus was having some cycling issues with the soft loaded 180's. So I clipped it down several different times but this ended up letting the bolt cycle too fast so I added the XH buffer to slow down the cycling. So far it cycles my 150 loads perfectly, still have some testing to do on the slow 180's..... But also remember I am running an A5 buffer tube and funny that no one makes specific springs designed for an A5 tube (You can buy Carbine or Rifle springs and Tubbs only sells the one length) so clipping a spring is somewhat customizing it for the A5 tube. It now has less tension than a full rifle spring but considerably more than a carbine spring....

Clipping springs seems to work best with heavier than usual buffers since it is much like you mentioned, similar to opening an AGB. Yes an AGB can do the same thing but I do like to tinker and the LR308 is a fairly new adventure for me.... if you saw the targets I build it would make more sense, LOL

 

[Lawless]

While spring tuning and buffer weight can slow the action, it is ultimately gas that unlocks the bolt. Certainly spring pressure pushing on the BCG can affect bolt unlock, but tuning with spring and buffer is a very coarse adjustment compared to the fine adjustment of tuning the gas.

As an example, you say you can feel the BCG/buffer bump the extension upon cycling. This could be mitigated in a very fine adjustment by closing the gas enough to delay unlock until the gun cycles perfectly for you.

If a Tubb spring is allowing the buffer to slam the end of the extension then the gun needs less gas. The solution of a custom clipped spring to hide the issue could lead to functioning problems in different weather And like you already stated, with different ammo.

I would bet you could tune with an adjustable block to allow your light loads to function along with your supers with the same spring and buffer. What you’d be doing is setting the max gas making it to the key instead of the reactionary fix of spring pressure. At a minimum, a click adjustable block and the matter of a click or 2 is certainly simpler to do when switching loads than swapping springs (and you may not even have to do that)

Most every big AR is overgassed, spring and buffer weight mask the problem. I understand your wanting a simple approach, but an adjustable block is as simple as it gets, especially one with clicks.

 

[KTAK]

Wouldn't it be nice if the barrel manufacturers would reduce the port size in the barrels they make... With all the overgassed large frames out there, it makes you wonder why they all seem to do it.

And I am not fooling myself, tuning the rifle for my primary load may not work for the soft 180's but that's OK as it was mostly intended as a really soft hunting round I loaded for some women shooters that wanted a softer recoil in bolt rifles.

Someday I may end up with an AGB but for now I have to live with the fixed one that came on the upper. Getting it to run the way I want has been an adventure well worth taking.

 

[hlee]

Has $100s in various weights of buffers and springs, and spends his days mixing and matching heavy/light buffers with heavy/light springs and long/short springs. Won't use a detent adjustable gas block because he likes things simple...

 

[Black max]

Clint only recommends the use of his 308 spring with his buffer. I'm shooting an 18" rifle gas suppressed 100% of the time and it is dead reliable. I'm also using an SLR gas block as well so ymmv.

 

[KTAK]

When I got my buffer from him, he only asked if I needed a spring. Wasn’t concerned about whose spring I had

Other interesting fact is that the XH buffer was designed to slow the cyclic rate of full auto M16’s according to his website...

 

[Black max]

When I got my buffer from him, he only asked if I needed a spring. Wasn’t concerned about whose spring I had

Other interesting fact is that the XH buffer was designed to slow the cyclic rate of full auto M16’s according to his website...

I would call and ask him. I called him when I was building mine and told him my goals which were, ubr stock, 18" rifle gas and a suppressor. He recommended XH carbine buffer and his spring. He would probably be more help than your going to get in this thread.

 

[Snuby642]

So the way I read this is you stuck a rifle lenght buffer into a (intermediate) carbine length tube.

And it smacks the back.

Yes!

Cutting springs or adding agb wont fix that.

 

[Lawless]

So the way I read this is you stuck a rifle lenght buffer into a (intermediate) carbine length tube.

And it smacks the back.

Yes!

Cutting springs or adding agb wont fix that.

No, he used an 8.5oz carbine buffer but when he uses the Tubbs spring in place of his cut spring he gets hard buffer contact on the rear of the extension. The rifle wouldn’t function at all with a rifle buffer in a carbine tube.

 

[hlee]

Is there something someone can use to modulate the force of the carrier's rearward travel? ?‍ Inquiring minds want to know.

 

[KTAK]

Has $100s in various weights of buffers and springs, and spends his days mixing and matching heavy/light buffers with heavy/light springs and long/short springs. Won't use a detent adjustable gas block because he likes things simple...

I guess I have to explain simple to you. When I put my rifle together, I purchased a complete assembled upper. It was fitted with a fixed gas block. Last time I checked it was far simpler to change a buffer than to change a gas block... I think it took all of 3 seconds. Yes I like simple....

A gas block with a simple hole runs about $28 and needs virtually zero maintenance. Adjustable runs about $100 because of extra machine work, screws and detents and will require more maintenance, probably not a lot but more....

As for all those extra buffers and springs.... The original intent was to use a carbine stock, so I bought a carbine spring, all of $6 and the heaviest buffer I knew about at the time was an H3, $41 if I remember correctly. (If I had known about Heavy Buffers at the time I would have started with one of Clints buffers.) DPMS rifle spring was all of $9 and only have one. Where exactly are $100's of dollars in extra unused parts?

The Tubbs spring, which by the way was the original idea for this post, is on it's way back to the place of purchase for a refund....

Funny, but not once have I said a single derogatory thing about AGB's. I know they work, I just chose to take a different path, one that I am very familiar with and know that it also works....

 

[KTAK]

I would call and ask him. I called him when I was building mine and told him my goals which were, ubr stock, 18" rifle gas and a suppressor. He recommended XH carbine buffer and his spring. He would probably be more help than your going to get in this thread.

Sadly some of the other responses are exactly why adults abandon forums.... LOL

 

[Snuby642]

Snuby642 stands corrected.

Misread post, my bad.

In my defense have never had that happen that I can recall.

Maybe tubbs never tested the a5 length?

 

[KTAK]

I find it odd that Tubbs only offers 1 size fits all.....

 

[TonyTheTiger]

I find it odd that Tubbs only offers 1 size fits all.....

Yeah I've considered buying them before but that part weirds me out.

 

[Snuby642]

I find that odd ad well but I only use carbine length systems so not a good judge of others.

I did accidentally order a rifle lenght buffer once and yes it does not work.

Oops.

New realm of malfunction. Lol

 

[KTAK]

Yeah I've considered buying them before but that part weirds me out.

I only tried it because of I have seen a lot of positive feedback. Sadly it did not work well in my 308

 

[KTAK]

I find that odd ad well but I only use carbine length systems so not a good judge of others.

I did accidentally order a rifle lenght buffer once and yes it does not work.

Oops.

New realm of malfunction. Lol

Maybe a carbine tube is the magic length for the Tubb spring in a 308, it did fall right in the middle between a carbine spring and my clipped rifle spring when comparing the force required to pull the charge handle.

 

[hlee]

Cut springs. Multiple springs. Multiple buffers. When did you buy the rifle? And it still doesn't work? And you're now on a forum trying to figure it out? That's the opposite of easy. And maybe you rate your time as "no cost" but I've got other shit to do than dick with a finicky rifle. Knock out the pins. Replace the gas block. That's the easy button.

Assuming the spring and buffer are the correct length for the receiver extension, and that the gas port is large enough to run the action when full open, a good adjustable gas block can be tuned run with virtually any spring/buffer/carrier/ammo combination. And, can be adjusted on the fly for different ammo. Want to shoot supers and subs, suppressed and unsuppressed? Dial the gas up and down as necessary.

But, if adulting on snipershide is too much for you...

 

[KTAK]

Cut springs. Multiple springs. Multiple buffers. When did you buy the rifle? And it still doesn't work? And you're now on a forum trying to figure it out? That's the opposite of easy. And maybe you rate your time as "no cost" but I've got other shit to do than dick with a finicky rifle. Knock out the pins. Replace the gas block. That's the easy button.

Assuming the spring and buffer are the correct length for the receiver extension, and that the gas port is large enough to run the action when full open, a good adjustable gas block can be tuned run with virtually any spring/buffer/carrier/ammo combination. And, can be adjusted on the fly for different ammo. Want to shoot supers and subs, suppressed and unsuppressed? Dial the gas up and down as necessary.

But, if adulting on snipershide is too much for you...

View attachment 7173520

Never said it didn't function, it has functioned from day one. And never asked for any help getting it to function.... Just sharing what I have learned about my rifle and the Tubbs spring.... Don't know who brought up the whole AGB thing....

 

[Snuby642]

Dear baby jesus, please don't add adjustable silent captured buffers to the mosh pit.

I have avoided agb for years (old guy)
But have 3 carbines not perfect, so shamefully may have to give in.

I fully get the OP's position on that.

 

[KTAK]

Dear baby jesus, please don't add adjustable silent captured buffers to the mosh pit.

I have avoided agb for years (old guy)
But have 3 carbines not perfect, so shamefully may have to give in.

I fully get the OP's position on that.

From one old guy to another, that was funny!

 

[Snuby642]

Maybe kestrel will ad a function to help us decide shot for shot. Lol

 

[Dolomite_Supafly]

Is there something someone can use to modulate the force of the carrier's rearward travel? ?‍ Inquiring minds want to know.

You can use an adjustable gas block to reduce carrier speed and felt recoil. Also using lighter weight components can help. I install and adjustable gas block on every AR barrel I buy.

I remove the weights from my buffers and fill them 1/2 way with powdered copper. It is lighter and works like a dead blow hammer to reduce bolt bounce.

Many, many moons ago I shortened a carbine buffer and installed copper powder. To take up the space removed I made a plastic buffer that went in the buffer tube first on the other end of the recoil spring. And in the middle of the plastic buffer I installed a heavy spring. It acted like a hydraulic buffer and definitely changed how the recoil felt.

Here is s picture of a prototype to see if it would work.