View Full Version : How long is a KAC buffer spring?
I just picked up my first KAC SR 15. Very excited about the purchase. As I was examining the parts and switching things around, I pulled the buffer spring and compared it to my new Sprinco "blue" carbine spring. There is a noticeable difference in length. I compared it to another carbine length spring and still it was shorter. Is that normal? Will the rifle functional normal if I use the Sprinco?
Just trying to understand this piece of art. Thanks
:)
-Edited by Robb Jensen so as to not imply that KAC springs are somehow defective.
Robb Jensen
03-16-11, 21:18
I just picked up my first KAC SR 15. Very excited about the purchase. As I was examining the parts and switching things around, I pulled the buffer spring and compared it to my new Sprinco "blue" carbine spring. There is a noticeable difference in length. I compared it to another carbine length spring and still it was shorter. Is that normal? Will the rifle functional normal if I use the Sprinco?
Just trying to understand this piece of art. Thanks
:)
Before you call the KAC spring 'short' what was it's actual length?
I don't know it's length by design. It may be exact length per KAC spec. I'm just saying, it's shorter than two other carbine length springs I have.
I was going to use the Sprinco, but now I'm not sure I can. I was unable to find any specifics in the owners manual and or at the Knights website. As I said, I'm just trying to understand the makeup of this rifle. Any input is helpful.
Whootsinator
03-16-11, 21:47
Get a ruler or measuring tape and measure it.
Get a ruler or measuring tape and measure it.
LOL! That's what you meant.
Don't laugh, but it's exactly between 10.25" and 10.50". I'm not good with measurements. :haha:
LOL! That's what you meant.
Don't laugh, but it's exactly between 10.25" and 10.50". I'm not good with measurements. :haha:
Carbine springs are from 10 1/16" to 11 1/4"
Carbine springs are from 10 1/16" to 11 1/4"
So, does that mean I can swap springs and not alter the functioning of the SR 15? I was beginning to assume the "shortened" spring and light weight buffer where tuned to the pressure coming from the gas block. And that a longer, maybe stiffer spring, and heavier buffer wouldn't cycle properly. Is that the case? :confused:
So, does that mean I can swap springs and not alter the functioning of the SR 15? I was beginning to assume the "shortened" spring and light weight buffer where tuned to the pressure coming from the gas block. And that a longer, maybe stiffer spring, and heavier buffer wouldn't cycle properly. Is that the case? :confused:
How much do you want to know about coil springs? :p The length at equilibrium (when you pull it out) is less important than the amount of displacement it has to work with and the force required to return the bolt to battery.
The important thing is: does it function?
How much do you want to know about coil springs? :p The length at equilibrium (when you pull it out) is less important than the amount of displacement it has to work with and the force required to return the bolt to battery.
The important thing is: does it function?
Yes. It functions. But, I'm still not getting my question answered. Can you swap out buffer springs in the SR15 and get the same result? Has any SR15 owner swapped out their buffer spring (to a Sprinco or similar) with no resulting issues? I guess I'll have to do a range test and find out first hand. :eek: A novel idea!
Robb Jensen
03-17-11, 09:31
Mil-spec for a CARbine buffer length spring is 10 1/16" minimum to a 11 1/4" maximum. These are music wire springs.
Extra power chrome silicon springs are always longer. This is why I like standard rate chrome silicon springs from Brownells, new CARbine versions of these are 10 1/2" when new, I'm a bit anal and change them out when they reach 10 1/4".
militarymoron
03-17-11, 10:45
Yes. It functions. But, I'm still not getting my question answered. Can you swap out buffer springs in the SR15 and get the same result?
that's because there isn't a 'yes/no' answer to your question without more information. if you swap out springs, unless they're identical, something's going to change, and you're not going to get the same 'result'. if by 'result', you mean 'cycle, lock back on empty mag', then the result may vary depending on the ammo you use. if by 'result', you also mean 'have the same recoil impulse, ejection pattern etc', then probably not. unless the springs are identical, something is going to change, and this applies to all rifles, not just the SR15.
i've swapped out regular carbine springs with the extra strength sprinco before, and it'd function with full power ammo but wasn't consistent with lower power ammo.
you're on the right track - the only real answer is to test your particular spring/ammo combo on your rifle.
Why would you want to change it if its doing its job correctly? Wait until it wears out.
EzGoingKev
03-19-11, 18:13
I just picked up my first KAC SR 15. Very excited about the purchase. As I was examining the parts and switching things around, I pulled the buffer spring and compared it to my new Sprinco "blue" carbine spring. There is a noticeable difference in length. I compared it to another carbine length spring and still it was shorter. Is that normal? Will the rifle functional normal if I use the Sprinco?
Just trying to understand this piece of art. Thanks
:)
-Edited by Robb Jensen so as to not imply that KAC springs are somehow defective.
I am just trying to understand why you would feel the need to swap parts on something you consider a "piece of art"?
Did you pick it up used and were worried about parts being worn out?
The length at equilibrium (when you pull it out) is less important than the amount of displacement it has to work with and the force required to return the bolt to battery.
Absolutely correct.
Springs are designed to work within a certain harmonic range. If the application causes it to be out of that range then you have the incorrect spring.
My SR-15 spring is 10.5''. Don't worry about it. This gun doesn't need spring/buffer tinkering, it comes tuned by design from the factory. Putting a different spring in it is probably a downgrade. The way it shoots is proof of this, so soft shooting.
Unless you are going to run a suppressor or cut the barrel or something, leave it alone.
Powered by vBulletin® Version 4.2.5 Copyright © 2024 vBulletin Solutions, Inc. All rights reserved.