How is the Buffer selected, Carbine, H, H2, H3, what do the  different weight buffers do?

What is the difference between a carbine and standard buffer?

What Buffer Spring ?  standard, heavy, H2, H3 ?

I am building my first Stripped lower, for 5.56 The  LPK is installed, except for the buffer tube, and parts.

I selected a Mil Spec
Carbine Extension tube 6 position,
Carbine Stock Latch plate,
Castle Nut,
Carbine buffer Standard weight,
Heaver Buffer spring.

I selected the heavier spring because it was recommended.

Tactical Springs LLC M4 / CAR-15 Extra Power Chrome Silicon Carbine Buffer Spring in Hard Tube (RED Spring)

 "Extra-Power Buffer Spring, best option for 14.5" and 16" barrels with carbine length gas system platforms with standard front sight towers and H buffers, gas piston guns, and suppressed weapons. Color Coded RED."

Standard buffer because of cost.

Will this combination work for 5.56 gas upper and/or a piston upper?

My second Lower is for a .45 acp upper, what is best Buffer system for it?

What is the method of selecting these parts?

Thank You

buffers and springs come in basically 2 common sizes.   They are called rifle and carbine but really have nothing to do with the length of the barrel.

In carbine buffers there are many flavors.   Inside normal carbine buffers are 3 little cylindrical weights.   If they are all steel, its called a carbine buffer, if 2 steel and one tungsten, then its called H1, 2 tungsten +1 steel is H2 and 3 tungsten is H3.  Simple enough.   There is a little space so the weights shift back and forth.   This helps the bolt slam home and prevent bolt bounce.   Normal carbine buffers have worked for years.  The heavier ones help slow down the action, especially on full-auto.  Also they help reliability in shorter barrels, like 10.5".  

Then there are 9mm buffers.  Which are basically carbine sized, but made from solid steel.  The weight comes out close to H3.

What is the right one?   D:  all of the above.   Any of them will work.  If the basic one works then stick with it.  Same with the spring.   If the normal one works, then why mess with it.  

Some of this goes back to shooting style.  The speed shooters in IPSC or 3gun want the cycle as fast as possible.  So they use light buffers, light springs, and even low mass bolt carriers.  All of this makes the action really fast.   See JPrifles.com

Meanwhile, the other side want to reduce recoil and reduce the cyclic rate.  So then you see heavier buffers and springs.    Pistol calibers, suppressors, short barrels and full auto generally go this way.

Its one of those things where there is no right answer, there are only styles.   I run an H2 in my 10.5"

If you also have a 45 upper, then go heavy.

Thank you,



The .45 upper will work better with a heavy spring and heavy buffer?

"..Then there are 9mm buffers. Which are basically carbine sized, but made from

solid steel. The weight comes out close to H3...

Can I use an H3 buffer for the .45 if I can't find a 9mm Buffer?

Is a Gas buster handle needed in a piston upper?

On the same note... is the st-t2 buffer upgrade worth it from spikes?  Im building an M4 clone and have still yet to select a buffer for my magpul ctr

not at all. the gas buster handle is used to stop gases from exiting the space between the CH and the upper receiver. with a piston upper, there are no gases returning to the upper receiver.

I found a Spike's Tactical 9mm extended buffer  

hhttp://www.ar15.com/forums/topic.html?b=3&f=124&t=413166

Instead of weights, they use power to lessen noise.

ST-9X SS Extended 9mm buffer - 8.5 oz.

You should contact user "Slash", this is his chart, and his email at the bottom.  Lots of good info here.  He can set you up with one buffer which will work for all.

The spikes one, is longer, which should work with 45, but not with 223.  And I dont like having to separate the upper to get it open.

Thank you

I received an email from [email protected]  

An HSS Tungsten buffer should work well for your .223, you will need a dedicated .45 buffer for the AR-45.  The heavier buffers will make the gun run more smoothly, protect it from damage and reduce felt recoil.  
I recommend Wolff XP buffer springs for all applications.  They will outlast most other springs by a factor of 5:1.
I attached some files with more info and photos.
Thanks,
Clint Butler

I w3as looking at a few buffers here at:     www.biggerhammer.net/ar15/buffers/

If I want to use a 16" heavy barrel should I utilize the one for a HBAR?